In-class Exercise 4: Calibrating Spatial Interaction Models with R

Published

January 24, 2023

Modified

December 10, 2023

Overview

This in-class exercise is a continuation of Hands-on Exercise 3, In-class Exercise 3 and In-class Exercise 4: Preparing Spatial Interaction Modelling Variables. We will continue our journey of calibrating Spatial Interaction Models by using propulsiveness and attractiveness variables prepared in earlier in-class exercise.

Getting Started

For the purpose of this exercise, five r packages will be used. They are:

  • sf for importing, integrating, processing and transforming geospatial data.
  • tidyverse for importing, integrating, wrangling and visualising data.
  • tmap for plotting cartographicquality thematic maps.
  • performance for computing model comparison matrices such as rmse.
  • ggpubr for creating publication quality statistical graphics.
Do it yourself

Using the steps you learned in previous exercises, load the above packages onto R environment.

Show the code chunk
pacman::p_load(tmap, sf, performance, knitr,
               ggpubr, tidyverse)

The Data

This exercise is a continuation of Hands-on Exercise 3 and In-class Exercise 4: Preparing Spatial Interaction Modelling Variables. The following data will be used:

  • flow_data_tidy.rds, weekday morning peak passenger flows at planning subzone level.
  • mpsz.rds, URA Master Plan 2019 Planning Subzone boundary in simple feature tibble data frame format.
flow_data <- read_rds("data/rds/flow_data_tidy.rds")
glimpse(flow_data)
Rows: 14,734
Columns: 13
$ ORIGIN_SZ       <chr> "AMSZ01", "AMSZ01", "AMSZ01", "AMSZ01", "AMSZ01", "AMS…
$ DESTIN_SZ       <chr> "AMSZ01", "AMSZ02", "AMSZ03", "AMSZ04", "AMSZ05", "AMS…
$ TRIPS           <dbl> 1998, 8289, 8971, 2252, 6136, 2148, 1620, 1925, 1773, …
$ DIST            <dbl> 50.0000, 810.4491, 1360.9294, 840.4432, 1076.7916, 805…
$ ORIGIN_AGE7_12  <dbl> 310, 310, 310, 310, 310, 310, 310, 310, 310, 310, 310,…
$ ORIGIN_AGE13_24 <dbl> 710, 710, 710, 710, 710, 710, 710, 710, 710, 710, 710,…
$ ORIGIN_AGE25_64 <dbl> 2780, 2780, 2780, 2780, 2780, 2780, 2780, 2780, 2780, …
$ DESTIN_AGE7_12  <dbl> 310.00, 1140.00, 1010.00, 980.00, 810.00, 1050.00, 420…
$ DESTIN_AGE13_24 <dbl> 710.00, 2770.00, 2650.00, 2000.00, 1920.00, 2390.00, 1…
$ DESTIN_AGE25_64 <dbl> 2780.00, 15700.00, 14240.00, 11320.00, 9650.00, 12460.…
$ SCHOOL_COUNT    <dbl> 0.99, 2.00, 2.00, 1.00, 3.00, 2.00, 0.99, 0.99, 3.00, …
$ BUSINESS_COUNT  <dbl> 1.00, 0.99, 6.00, 0.99, 0.99, 0.99, 1.00, 117.00, 0.99…
$ geometry        <LINESTRING [m]> LINESTRING (29501.77 39419...., LINESTRING …

Notice that this sf tibble data.frame includes two additional fields namely: SCHOOL_COUNT and BUSINESS_COUNT. Both of them will be used as attractiveness variables when calibrating origin constrained SIM.

The code chunk below is used to display the first five columns and rows of flow_data.

kable(head(flow_data[, 1:5], n = 5))
ORIGIN_SZ DESTIN_SZ TRIPS DIST ORIGIN_AGE7_12 geometry
AMSZ01 AMSZ01 1998 50.0000 310 LINESTRING (29501.77 39419….
AMSZ01 AMSZ02 8289 810.4491 310 LINESTRING (29501.77 39419….
AMSZ01 AMSZ03 8971 1360.9294 310 LINESTRING (29501.77 39419….
AMSZ01 AMSZ04 2252 840.4432 310 LINESTRING (29501.77 39419….
AMSZ01 AMSZ05 6136 1076.7916 310 LINESTRING (29501.77 39419….
Important

Notice that this data.frame include intra-zonal flow.

Preparing inter-zonal flow data

In general, we will calibrate separate Spatial Interaction Models for inter- and intra-zonal flows. In this hands-on exercise, we will focus our attention on inter-zonal flow. Hence, we need to exclude the intra-zonal flow from flow_data.

First, two new columns called FlowNoIntra and offset will be created by using the code chunk below.

flow_data$FlowNoIntra <- ifelse(
  flow_data$ORIGIN_SZ == flow_data$DESTIN_SZ, 
  0, flow_data$TRIPS)
flow_data$offset <- ifelse(
  flow_data$ORIGIN_SZ == flow_data$DESTIN_SZ, 
  0.000001, 1)

According to the syntax used to derive values in FlowNoIntra field, all intra-zonal flow will be given a value of 0 or else the original flow values will be inserted.

Next, inter-zonal flow will be selected from flow_data and save into a new output data.frame called inter_zonal_flow by using the code chunk below.

inter_zonal_flow <- flow_data %>%
  filter(FlowNoIntra > 0)

You are ready to calibrate the Spatial Interaction Models now.

Calibrating Spatial Interaction Models

In this section, we will focus on calibrating an origin constrained SIM and a doubly constrained by using flow_data prepared. They complement what you have learned in Hands-on Exercise 3.

Note

Students are encouraged to revise the lesson slides as well as Sub-section 2.2 of Kingsley E. Haynes and A. Stewart Fotheringham (2020) Gravity and Spatial Interaction Models.

Origin- (Production-) constrained Model

Figure below shows the general formula of the origin-constrained model.

Code chunk below shows the calibration of the model by using glm() of R and flow_data.

orcSIM_Poisson <- glm(formula = TRIPS ~ 
                ORIGIN_SZ +
                log(SCHOOL_COUNT) +
                log(BUSINESS_COUNT) +
                log(DIST) - 1,
              family = poisson(link = "log"),
              data = inter_zonal_flow,
              na.action = na.exclude)
summary(orcSIM_Poisson)
Things to learning from the conde chunk
  • For origin-constrained model, only explanatory variables representing the attractiveness at the destinations will be used.
  • All the explanatory variables including distance will be log transformed.
  • ORIGIN_SZ is used to model 𝜇𝑖 . It must be in categorical data type.
  • It is important to note that -1 is added in the equation after the distance variable. The -1 serves the purpose of removing the intercept that by default, glm will insert into the model.

Call:
glm(formula = TRIPS ~ ORIGIN_SZ + log(SCHOOL_COUNT) + log(BUSINESS_COUNT) + 
    log(DIST) - 1, family = poisson(link = "log"), data = inter_zonal_flow, 
    na.action = na.exclude)

Coefficients:
                      Estimate Std. Error  z value Pr(>|z|)    
ORIGIN_SZAMSZ01     19.8739840  0.0047627  4172.84   <2e-16 ***
ORIGIN_SZAMSZ02     20.5902203  0.0042786  4812.33   <2e-16 ***
ORIGIN_SZAMSZ03     20.2327026  0.0045531  4443.70   <2e-16 ***
ORIGIN_SZAMSZ04     19.7744438  0.0049837  3967.79   <2e-16 ***
ORIGIN_SZAMSZ05     19.6574529  0.0056396  3485.61   <2e-16 ***
ORIGIN_SZAMSZ06     19.9659115  0.0048946  4079.16   <2e-16 ***
ORIGIN_SZAMSZ07     18.6746164  0.0096316  1938.90   <2e-16 ***
ORIGIN_SZAMSZ08     19.2701601  0.0090776  2122.82   <2e-16 ***
ORIGIN_SZAMSZ09     19.9889467  0.0052858  3781.64   <2e-16 ***
ORIGIN_SZAMSZ10     20.3422035  0.0045778  4443.62   <2e-16 ***
ORIGIN_SZAMSZ11     18.3944113  0.0129212  1423.58   <2e-16 ***
ORIGIN_SZAMSZ12     18.3484209  0.0109652  1673.33   <2e-16 ***
ORIGIN_SZBDSZ01     20.9668587  0.0043388  4832.36   <2e-16 ***
ORIGIN_SZBDSZ02     20.4059518  0.0050601  4032.75   <2e-16 ***
ORIGIN_SZBDSZ03     20.6725514  0.0045276  4565.93   <2e-16 ***
ORIGIN_SZBDSZ04     21.6703853  0.0038930  5566.44   <2e-16 ***
ORIGIN_SZBDSZ05     20.7497445  0.0046085  4502.46   <2e-16 ***
ORIGIN_SZBDSZ06     20.9119361  0.0046432  4503.77   <2e-16 ***
ORIGIN_SZBDSZ07     18.9749815  0.0097896  1938.28   <2e-16 ***
ORIGIN_SZBDSZ08     19.1933901  0.0091312  2101.95   <2e-16 ***
ORIGIN_SZBKSZ01     19.5422606  0.0064732  3018.96   <2e-16 ***
ORIGIN_SZBKSZ02     20.1748913  0.0050076  4028.89   <2e-16 ***
ORIGIN_SZBKSZ03     20.3984624  0.0047226  4319.35   <2e-16 ***
ORIGIN_SZBKSZ04     19.6182212  0.0059652  3288.76   <2e-16 ***
ORIGIN_SZBKSZ05     19.6033818  0.0063181  3102.74   <2e-16 ***
ORIGIN_SZBKSZ06     19.7145224  0.0056372  3497.20   <2e-16 ***
ORIGIN_SZBKSZ07     20.4237448  0.0041912  4873.03   <2e-16 ***
ORIGIN_SZBKSZ08     19.7992538  0.0050405  3928.02   <2e-16 ***
ORIGIN_SZBKSZ09     19.7821586  0.0055558  3560.66   <2e-16 ***
ORIGIN_SZBLSZ01     17.7977276  0.0149058  1194.01   <2e-16 ***
ORIGIN_SZBLSZ02     17.4287491  0.0192364   906.03   <2e-16 ***
ORIGIN_SZBLSZ03     16.5884288  0.0459848   360.74   <2e-16 ***
ORIGIN_SZBLSZ04     17.7851626  0.0232823   763.89   <2e-16 ***
ORIGIN_SZBMSZ01     20.0751840  0.0052887  3795.89   <2e-16 ***
ORIGIN_SZBMSZ02     18.6956140  0.0066656  2804.80   <2e-16 ***
ORIGIN_SZBMSZ03     19.3204425  0.0054755  3528.56   <2e-16 ***
ORIGIN_SZBMSZ04     19.4724220  0.0049390  3942.59   <2e-16 ***
ORIGIN_SZBMSZ05     16.9581801  0.0168804  1004.61   <2e-16 ***
ORIGIN_SZBMSZ06     16.9898638  0.0181852   934.27   <2e-16 ***
ORIGIN_SZBMSZ07     19.2868403  0.0056231  3429.91   <2e-16 ***
ORIGIN_SZBMSZ08     19.1477543  0.0055918  3424.28   <2e-16 ***
ORIGIN_SZBMSZ09     18.7564539  0.0086298  2173.46   <2e-16 ***
ORIGIN_SZBMSZ10     18.3617854  0.0089250  2057.35   <2e-16 ***
ORIGIN_SZBMSZ11     18.9167941  0.0063340  2986.54   <2e-16 ***
ORIGIN_SZBMSZ12     18.7874661  0.0093024  2019.63   <2e-16 ***
ORIGIN_SZBMSZ13     19.5654046  0.0057517  3401.70   <2e-16 ***
ORIGIN_SZBMSZ14     19.0685619  0.0063346  3010.24   <2e-16 ***
ORIGIN_SZBMSZ15     19.4403124  0.0058147  3343.30   <2e-16 ***
ORIGIN_SZBMSZ16     18.4469203  0.0092638  1991.28   <2e-16 ***
ORIGIN_SZBMSZ17     18.3430175  0.0157692  1163.22   <2e-16 ***
ORIGIN_SZBPSZ01     20.1806714  0.0053660  3760.81   <2e-16 ***
ORIGIN_SZBPSZ02     19.8116707  0.0061485  3222.19   <2e-16 ***
ORIGIN_SZBPSZ03     19.8467602  0.0059769  3320.57   <2e-16 ***
ORIGIN_SZBPSZ04     20.4613200  0.0048398  4227.72   <2e-16 ***
ORIGIN_SZBPSZ05     20.5379711  0.0043769  4692.39   <2e-16 ***
ORIGIN_SZBPSZ06     18.8948034  0.0093668  2017.21   <2e-16 ***
ORIGIN_SZBPSZ07     19.4104568  0.0087961  2206.70   <2e-16 ***
ORIGIN_SZBSSZ01     20.0139503  0.0056561  3538.45   <2e-16 ***
ORIGIN_SZBSSZ02     20.2543885  0.0047198  4291.38   <2e-16 ***
ORIGIN_SZBSSZ03     19.5428803  0.0052713  3707.41   <2e-16 ***
ORIGIN_SZBTSZ01     20.0198045  0.0058541  3419.77   <2e-16 ***
ORIGIN_SZBTSZ02     19.3618525  0.0081472  2376.51   <2e-16 ***
ORIGIN_SZBTSZ03     19.5883853  0.0068935  2841.59   <2e-16 ***
ORIGIN_SZBTSZ04     18.7720238  0.0103909  1806.58   <2e-16 ***
ORIGIN_SZBTSZ05     18.8069026  0.0120628  1559.08   <2e-16 ***
ORIGIN_SZBTSZ06     18.7068633  0.0094575  1978.00   <2e-16 ***
ORIGIN_SZBTSZ07     17.6292257  0.0141551  1245.43   <2e-16 ***
ORIGIN_SZBTSZ08     18.6989374  0.0109610  1705.94   <2e-16 ***
ORIGIN_SZCBSZ01     18.2189868  0.0548317   332.27   <2e-16 ***
ORIGIN_SZCCSZ01     18.9734563  0.0139450  1360.59   <2e-16 ***
ORIGIN_SZCHSZ01     19.5955119  0.0121035  1619.00   <2e-16 ***
ORIGIN_SZCHSZ02     19.3320960  0.0081620  2368.55   <2e-16 ***
ORIGIN_SZCHSZ03     21.2164518  0.0063552  3338.43   <2e-16 ***
ORIGIN_SZCKSZ01     20.1046845  0.0049333  4075.29   <2e-16 ***
ORIGIN_SZCKSZ02     20.5371946  0.0050256  4086.53   <2e-16 ***
ORIGIN_SZCKSZ03     20.7210560  0.0042184  4912.07   <2e-16 ***
ORIGIN_SZCKSZ04     21.4013886  0.0042524  5032.80   <2e-16 ***
ORIGIN_SZCKSZ05     20.9413146  0.0049434  4236.18   <2e-16 ***
ORIGIN_SZCKSZ06     20.2557727  0.0071832  2819.88   <2e-16 ***
ORIGIN_SZCLSZ01     19.3383703  0.0076634  2523.46   <2e-16 ***
ORIGIN_SZCLSZ02     18.5226956  0.0135522  1366.77   <2e-16 ***
ORIGIN_SZCLSZ03     19.0225512  0.0080145  2373.51   <2e-16 ***
ORIGIN_SZCLSZ04     20.7981505  0.0042400  4905.22   <2e-16 ***
ORIGIN_SZCLSZ05     18.3015625  0.0146815  1246.58   <2e-16 ***
ORIGIN_SZCLSZ06     20.8207386  0.0039567  5262.09   <2e-16 ***
ORIGIN_SZCLSZ07     19.6728958  0.0054199  3629.76   <2e-16 ***
ORIGIN_SZCLSZ08     20.0851929  0.0056956  3526.43   <2e-16 ***
ORIGIN_SZCLSZ09     18.5749589  0.0165415  1122.93   <2e-16 ***
ORIGIN_SZDTSZ02     15.8276209  0.0833992   189.78   <2e-16 ***
ORIGIN_SZDTSZ03     16.2512838  0.0737972   220.22   <2e-16 ***
ORIGIN_SZDTSZ13     16.7744385  0.0312450   536.87   <2e-16 ***
ORIGIN_SZGLSZ01     18.2368248  0.0096104  1897.62   <2e-16 ***
ORIGIN_SZGLSZ02     19.8705255  0.0049014  4054.06   <2e-16 ***
ORIGIN_SZGLSZ03     19.8249435  0.0053109  3732.85   <2e-16 ***
ORIGIN_SZGLSZ04     20.7800335  0.0041261  5036.20   <2e-16 ***
ORIGIN_SZGLSZ05     20.6040494  0.0043049  4786.23   <2e-16 ***
ORIGIN_SZHGSZ01     20.0273475  0.0044824  4468.04   <2e-16 ***
ORIGIN_SZHGSZ02     20.2480656  0.0044575  4542.47   <2e-16 ***
ORIGIN_SZHGSZ03     20.0756442  0.0049003  4096.81   <2e-16 ***
ORIGIN_SZHGSZ04     20.7577748  0.0040465  5129.84   <2e-16 ***
ORIGIN_SZHGSZ05     20.9779992  0.0040123  5228.42   <2e-16 ***
ORIGIN_SZHGSZ06     19.7403058  0.0054229  3640.20   <2e-16 ***
ORIGIN_SZHGSZ07     20.1896268  0.0046051  4384.22   <2e-16 ***
ORIGIN_SZHGSZ08     19.8646492  0.0052403  3790.72   <2e-16 ***
ORIGIN_SZHGSZ09     18.3647736  0.0069196  2654.04   <2e-16 ***
ORIGIN_SZHGSZ10     16.8720475  0.0421046   400.72   <2e-16 ***
ORIGIN_SZJESZ01     20.2673794  0.0046723  4337.79   <2e-16 ***
ORIGIN_SZJESZ02     20.0595982  0.0046503  4313.61   <2e-16 ***
ORIGIN_SZJESZ03     19.9128778  0.0049848  3994.75   <2e-16 ***
ORIGIN_SZJESZ04     18.5053667  0.0099227  1864.94   <2e-16 ***
ORIGIN_SZJESZ05     17.8172930  0.0138840  1283.29   <2e-16 ***
ORIGIN_SZJESZ06     20.0124157  0.0045009  4446.36   <2e-16 ***
ORIGIN_SZJESZ07     18.1821423  0.0117267  1550.49   <2e-16 ***
ORIGIN_SZJESZ08     18.8713046  0.0116456  1620.46   <2e-16 ***
ORIGIN_SZJESZ09     20.5535527  0.0048456  4241.72   <2e-16 ***
ORIGIN_SZJESZ10     18.4922322  0.0191243   966.95   <2e-16 ***
ORIGIN_SZJESZ11     18.2891211  0.0197114   927.85   <2e-16 ***
ORIGIN_SZJWSZ01     20.4912737  0.0063102  3247.35   <2e-16 ***
ORIGIN_SZJWSZ02     20.8236694  0.0042249  4928.82   <2e-16 ***
ORIGIN_SZJWSZ03     21.2587613  0.0039733  5350.40   <2e-16 ***
ORIGIN_SZJWSZ04     20.3816464  0.0046199  4411.67   <2e-16 ***
ORIGIN_SZJWSZ05     18.0607448  0.0128857  1401.61   <2e-16 ***
ORIGIN_SZJWSZ06     18.7015202  0.0107614  1737.83   <2e-16 ***
ORIGIN_SZJWSZ07     17.3991822  0.0277096   627.91   <2e-16 ***
ORIGIN_SZJWSZ08     21.8044465  0.0037356  5836.95   <2e-16 ***
ORIGIN_SZJWSZ09     21.5414930  0.0036033  5978.19   <2e-16 ***
ORIGIN_SZKLSZ01     20.0307712  0.0047868  4184.59   <2e-16 ***
ORIGIN_SZKLSZ02     19.0634769  0.0062318  3059.05   <2e-16 ***
ORIGIN_SZKLSZ03     19.2685700  0.0057172  3370.25   <2e-16 ***
ORIGIN_SZKLSZ04     17.7085067  0.0119809  1478.06   <2e-16 ***
ORIGIN_SZKLSZ05     18.6384471  0.0107596  1732.26   <2e-16 ***
ORIGIN_SZKLSZ06     13.7280296  0.1857160    73.92   <2e-16 ***
ORIGIN_SZKLSZ07     18.6425146  0.0084952  2194.47   <2e-16 ***
ORIGIN_SZKLSZ08     18.0928506  0.0101567  1781.37   <2e-16 ***
ORIGIN_SZLKSZ01     17.8907138  0.0397083   450.55   <2e-16 ***
ORIGIN_SZMDSZ01     18.7605188  0.0285455   657.22   <2e-16 ***
ORIGIN_SZMDSZ02     19.1533927  0.0102815  1862.90   <2e-16 ***
ORIGIN_SZMDSZ03     17.8404982  0.0169690  1051.36   <2e-16 ***
ORIGIN_SZMPSZ01     19.0765941  0.0083937  2272.74   <2e-16 ***
ORIGIN_SZMPSZ02     19.2162527  0.0068331  2812.24   <2e-16 ***
ORIGIN_SZMPSZ03     19.9965344  0.0054569  3664.44   <2e-16 ***
ORIGIN_SZMUSZ02     15.9130765  0.1037472   153.38   <2e-16 ***
ORIGIN_SZNTSZ01     17.0840999  0.0352513   484.64   <2e-16 ***
ORIGIN_SZNTSZ02     16.5792122  0.0233186   710.99   <2e-16 ***
ORIGIN_SZNTSZ03     18.9506415  0.0075957  2494.93   <2e-16 ***
ORIGIN_SZNTSZ05     15.8770261  0.0495825   320.21   <2e-16 ***
ORIGIN_SZNTSZ06     15.3997415  0.0557029   276.46   <2e-16 ***
ORIGIN_SZNVSZ01     20.2241694  0.0043487  4650.65   <2e-16 ***
ORIGIN_SZNVSZ02     19.1897826  0.0065383  2934.97   <2e-16 ***
ORIGIN_SZNVSZ03     18.8854268  0.0080459  2347.22   <2e-16 ***
ORIGIN_SZNVSZ04     18.8940191  0.0090985  2076.61   <2e-16 ***
ORIGIN_SZNVSZ05     17.6278585  0.0168107  1048.61   <2e-16 ***
ORIGIN_SZPGSZ01     19.4825220  0.0122960  1584.46   <2e-16 ***
ORIGIN_SZPGSZ02     19.4726761  0.0073116  2663.25   <2e-16 ***
ORIGIN_SZPGSZ03     20.5515713  0.0045631  4503.86   <2e-16 ***
ORIGIN_SZPGSZ04     21.0527131  0.0041500  5072.89   <2e-16 ***
ORIGIN_SZPGSZ05     20.1436604  0.0057267  3517.48   <2e-16 ***
ORIGIN_SZPLSZ01     19.1832002  0.0120006  1598.53   <2e-16 ***
ORIGIN_SZPLSZ02     18.8752206  0.0149740  1260.53   <2e-16 ***
ORIGIN_SZPLSZ03     18.1000818  0.0371769   486.86   <2e-16 ***
ORIGIN_SZPLSZ04     17.1730559  0.0370280   463.79   <2e-16 ***
ORIGIN_SZPLSZ05     17.9084439  0.0225031   795.82   <2e-16 ***
ORIGIN_SZPNSZ01     21.0804425  0.0044829  4702.41   <2e-16 ***
ORIGIN_SZPNSZ02     19.8822123  0.0111507  1783.05   <2e-16 ***
ORIGIN_SZPNSZ03     17.9293289  0.0193571   926.24   <2e-16 ***
ORIGIN_SZPNSZ04     17.1039594  0.0334954   510.64   <2e-16 ***
ORIGIN_SZPNSZ05     18.2543864  0.0275554   662.46   <2e-16 ***
ORIGIN_SZPRSZ01     19.8777935  0.0117586  1690.49   <2e-16 ***
ORIGIN_SZPRSZ02     21.0751780  0.0044832  4700.88   <2e-16 ***
ORIGIN_SZPRSZ03     20.6717019  0.0045577  4535.55   <2e-16 ***
ORIGIN_SZPRSZ04     19.6365125  0.0074923  2620.90   <2e-16 ***
ORIGIN_SZPRSZ05     21.3132151  0.0042119  5060.24   <2e-16 ***
ORIGIN_SZPRSZ06     18.9314574  0.0117278  1614.24   <2e-16 ***
ORIGIN_SZPRSZ07     17.2822918  0.0162430  1063.98   <2e-16 ***
ORIGIN_SZPRSZ08     19.9267642  0.0062298  3198.62   <2e-16 ***
ORIGIN_SZQTSZ01     19.7357175  0.0066359  2974.08   <2e-16 ***
ORIGIN_SZQTSZ02     19.2082141  0.0061402  3128.26   <2e-16 ***
ORIGIN_SZQTSZ03     19.7771883  0.0056220  3517.83   <2e-16 ***
ORIGIN_SZQTSZ04     18.7114421  0.0072842  2568.76   <2e-16 ***
ORIGIN_SZQTSZ05     19.3049324  0.0062401  3093.69   <2e-16 ***
ORIGIN_SZQTSZ06     19.2643228  0.0065590  2937.09   <2e-16 ***
ORIGIN_SZQTSZ07     18.5697347  0.0095373  1947.06   <2e-16 ***
ORIGIN_SZQTSZ08     19.6147001  0.0061330  3198.21   <2e-16 ***
ORIGIN_SZQTSZ09     19.2550793  0.0069947  2752.82   <2e-16 ***
ORIGIN_SZQTSZ10     19.5801866  0.0064513  3035.07   <2e-16 ***
ORIGIN_SZQTSZ11     17.7398366  0.0143648  1234.95   <2e-16 ***
ORIGIN_SZQTSZ12     17.2420354  0.0186736   923.34   <2e-16 ***
ORIGIN_SZQTSZ13     19.3857418  0.0078878  2457.69   <2e-16 ***
ORIGIN_SZQTSZ14     18.1300753  0.0122096  1484.90   <2e-16 ***
ORIGIN_SZQTSZ15     19.4222283  0.0120871  1606.86   <2e-16 ***
ORIGIN_SZRCSZ01     18.1549045  0.0125108  1451.13   <2e-16 ***
ORIGIN_SZRCSZ06     18.8836400  0.0082161  2298.38   <2e-16 ***
ORIGIN_SZRVSZ01     16.7864438  0.0323796   518.43   <2e-16 ***
ORIGIN_SZRVSZ02     16.4203244  0.0276836   593.14   <2e-16 ***
ORIGIN_SZRVSZ03     16.6453738  0.0244992   679.42   <2e-16 ***
ORIGIN_SZRVSZ04     15.9559213  0.0556344   286.80   <2e-16 ***
ORIGIN_SZRVSZ05     17.0476331  0.0164122  1038.71   <2e-16 ***
ORIGIN_SZSBSZ01     20.0417968  0.0062488  3207.29   <2e-16 ***
ORIGIN_SZSBSZ02     19.1869565  0.0081051  2367.26   <2e-16 ***
ORIGIN_SZSBSZ03     20.5769861  0.0045108  4561.70   <2e-16 ***
ORIGIN_SZSBSZ04     20.5154199  0.0050548  4058.57   <2e-16 ***
ORIGIN_SZSBSZ05     19.6250669  0.0065562  2993.35   <2e-16 ***
ORIGIN_SZSBSZ06     18.8419757  0.0171135  1101.00   <2e-16 ***
ORIGIN_SZSBSZ07     19.4897259  0.0124528  1565.09   <2e-16 ***
ORIGIN_SZSBSZ08     18.7027917  0.0140545  1330.73   <2e-16 ***
ORIGIN_SZSBSZ09     18.8893480  0.0088571  2132.67   <2e-16 ***
ORIGIN_SZSESZ02     20.8962192  0.0041665  5015.34   <2e-16 ***
ORIGIN_SZSESZ03     20.9452771  0.0039737  5270.94   <2e-16 ***
ORIGIN_SZSESZ04     20.6576142  0.0046364  4455.55   <2e-16 ***
ORIGIN_SZSESZ05     19.5170732  0.0058912  3312.92   <2e-16 ***
ORIGIN_SZSESZ06     20.7595824  0.0045747  4537.89   <2e-16 ***
ORIGIN_SZSESZ07     17.6888256  0.0195787   903.47   <2e-16 ***
ORIGIN_SZSGSZ01     19.1359250  0.0085781  2230.79   <2e-16 ***
ORIGIN_SZSGSZ02     18.5614369  0.0102037  1819.10   <2e-16 ***
ORIGIN_SZSGSZ03     19.9933176  0.0050434  3964.23   <2e-16 ***
ORIGIN_SZSGSZ04     20.2426871  0.0047211  4287.71   <2e-16 ***
ORIGIN_SZSGSZ05     18.0114965  0.0107743  1671.70   <2e-16 ***
ORIGIN_SZSGSZ06     20.2593194  0.0044538  4548.76   <2e-16 ***
ORIGIN_SZSGSZ07     19.0763664  0.0062968  3029.54   <2e-16 ***
ORIGIN_SZSKSZ01     19.9222451  0.0085136  2340.04   <2e-16 ***
ORIGIN_SZSKSZ02     20.8633383  0.0055248  3776.33   <2e-16 ***
ORIGIN_SZSKSZ03     19.6528148  0.0080534  2440.33   <2e-16 ***
ORIGIN_SZSKSZ04     18.0754470  0.0275771   655.45   <2e-16 ***
ORIGIN_SZSKSZ05     19.1192521  0.0155579  1228.91   <2e-16 ***
ORIGIN_SZSLSZ01     17.1501034  0.0329384   520.67   <2e-16 ***
ORIGIN_SZSLSZ04     19.5949774  0.0076753  2552.98   <2e-16 ***
ORIGIN_SZSRSZ01     16.9761403  0.0162020  1047.78   <2e-16 ***
ORIGIN_SZTHSZ01     17.9695687  0.0488559   367.81   <2e-16 ***
ORIGIN_SZTHSZ03     18.5427522  0.0223617   829.22   <2e-16 ***
ORIGIN_SZTHSZ04     17.4760374  0.0286247   610.52   <2e-16 ***
ORIGIN_SZTHSZ06     17.8401186  0.0183322   973.16   <2e-16 ***
ORIGIN_SZTMSZ01     20.3406361  0.0056607  3593.33   <2e-16 ***
ORIGIN_SZTMSZ02     22.0307026  0.0037386  5892.85   <2e-16 ***
ORIGIN_SZTMSZ03     21.3451920  0.0040606  5256.65   <2e-16 ***
ORIGIN_SZTMSZ04     20.6611593  0.0049896  4140.87   <2e-16 ***
ORIGIN_SZTMSZ05     19.3323133  0.0112868  1712.82   <2e-16 ***
ORIGIN_SZTNSZ01     17.9513571  0.0128266  1399.54   <2e-16 ***
ORIGIN_SZTNSZ02     18.0267387  0.0098372  1832.51   <2e-16 ***
ORIGIN_SZTNSZ03     17.7253700  0.0134668  1316.23   <2e-16 ***
ORIGIN_SZTNSZ04     19.4474075  0.0073760  2636.59   <2e-16 ***
ORIGIN_SZTPSZ01     19.1078631  0.0065635  2911.25   <2e-16 ***
ORIGIN_SZTPSZ02     20.2837634  0.0041411  4898.18   <2e-16 ***
ORIGIN_SZTPSZ03     19.1838238  0.0059552  3221.37   <2e-16 ***
ORIGIN_SZTPSZ04     19.1805388  0.0054778  3501.53   <2e-16 ***
ORIGIN_SZTPSZ05     19.3718076  0.0058610  3305.18   <2e-16 ***
ORIGIN_SZTPSZ06     19.6605723  0.0054968  3576.70   <2e-16 ***
ORIGIN_SZTPSZ07     19.4499807  0.0060491  3215.36   <2e-16 ***
ORIGIN_SZTPSZ08     18.7996538  0.0095757  1963.28   <2e-16 ***
ORIGIN_SZTPSZ09     19.0025110  0.0067068  2833.31   <2e-16 ***
ORIGIN_SZTPSZ10     18.8899657  0.0076094  2482.46   <2e-16 ***
ORIGIN_SZTPSZ11     19.6277780  0.0053983  3635.93   <2e-16 ***
ORIGIN_SZTPSZ12     19.1471104  0.0065742  2912.45   <2e-16 ***
ORIGIN_SZTSSZ01     17.4901113  0.0478954   365.17   <2e-16 ***
ORIGIN_SZTSSZ02     20.4997466  0.0081850  2504.55   <2e-16 ***
ORIGIN_SZTSSZ03     20.1076553  0.0084728  2373.19   <2e-16 ***
ORIGIN_SZTSSZ04     20.0646610  0.0089008  2254.26   <2e-16 ***
ORIGIN_SZTSSZ05     19.3962067  0.0151392  1281.19   <2e-16 ***
ORIGIN_SZTSSZ06     20.9235857  0.0178278  1173.65   <2e-16 ***
ORIGIN_SZWCSZ01     20.8411600  0.0086519  2408.86   <2e-16 ***
ORIGIN_SZWCSZ02     17.7355404  0.0328889   539.26   <2e-16 ***
ORIGIN_SZWCSZ03     14.9380886  0.1240699   120.40   <2e-16 ***
ORIGIN_SZWDSZ01     21.1969012  0.0037830  5603.23   <2e-16 ***
ORIGIN_SZWDSZ02     20.5930001  0.0044572  4620.13   <2e-16 ***
ORIGIN_SZWDSZ03     21.2521867  0.0041672  5099.85   <2e-16 ***
ORIGIN_SZWDSZ04     21.0702687  0.0048648  4331.13   <2e-16 ***
ORIGIN_SZWDSZ05     20.4008998  0.0051801  3938.35   <2e-16 ***
ORIGIN_SZWDSZ06     20.6669176  0.0049280  4193.78   <2e-16 ***
ORIGIN_SZWDSZ07     19.0500370  0.0082729  2302.71   <2e-16 ***
ORIGIN_SZWDSZ08     19.0816252  0.0080667  2365.49   <2e-16 ***
ORIGIN_SZWDSZ09     21.4182096  0.0040391  5302.73   <2e-16 ***
ORIGIN_SZYSSZ01     19.5355157  0.0057540  3395.14   <2e-16 ***
ORIGIN_SZYSSZ02     20.8737972  0.0048278  4323.64   <2e-16 ***
ORIGIN_SZYSSZ03     21.6614437  0.0040011  5413.81   <2e-16 ***
ORIGIN_SZYSSZ04     20.9305289  0.0043595  4801.10   <2e-16 ***
ORIGIN_SZYSSZ05     20.1727678  0.0058466  3450.34   <2e-16 ***
ORIGIN_SZYSSZ06     19.1481507  0.0116724  1640.47   <2e-16 ***
ORIGIN_SZYSSZ07     18.7919074  0.0141636  1326.78   <2e-16 ***
ORIGIN_SZYSSZ08     19.9733515  0.0061229  3262.07   <2e-16 ***
ORIGIN_SZYSSZ09     20.9366181  0.0040347  5189.15   <2e-16 ***
log(SCHOOL_COUNT)    0.4755516  0.0004701  1011.55   <2e-16 ***
log(BUSINESS_COUNT)  0.1796905  0.0001856   968.12   <2e-16 ***
log(DIST)           -1.6929522  0.0004093 -4136.01   <2e-16 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

(Dispersion parameter for poisson family taken to be 1)

    Null deviance: 189463537  on 14471  degrees of freedom
Residual deviance:  15526121  on 14189  degrees of freedom
AIC: 15615824

Number of Fisher Scoring iterations: 6
What can we learn from the report above?
  • the ⍺1 and ⍺2 of SCHOOL_COUNT and BUSINESS_COUNT are 0.4755516 and 0.1796905 respectively.

  • 𝛽, the distance decay parameter is -1.6929522

  • there are a series of parameters which are the vector of 𝜇𝑖 values associated with the origin constraints.

Goodness of fit

In statistical modelling, the next question we would like to answer is how well the proportion of variance in the dependent variable (i.e. TRIPS) that can be explained by the explanatory variables.

In order to provide answer to this question, R-squared statistics will be used. However, R-squared is not an output of glm(). Hence we will write a function called CalcRSquared by using the code chunk below.

CalcRSquared <- function(observed, estimated){
  r <- cor(observed, estimated)
  R2 <- r^2
  R2
}

NOw, we can examine how the constraints hold for destinations this time.

CalcRSquared(orcSIM_Poisson$data$TRIPS, orcSIM_Poisson$fitted.values)
[1] 0.4362208

With reference to the R-Squared above, we can conclude that the model accounts for about 44% of the variation of flows in the systems. Not bad, but not brilliant either.

Doubly constrained model

In this section, we will fit a doubly constrained SIM by using the general formula shown below:

and the code chunk used is shown below.

dbcSIM_Poisson <- glm(formula = TRIPS ~ 
                ORIGIN_SZ + 
                DESTIN_SZ +
                log(DIST),
              family = poisson(link = "log"),
              data = inter_zonal_flow,
              na.action = na.exclude)
summary(dbcSIM_Poisson)
Important

It is important to note that there is a slight change of the code chunk. I have removed the -1 which means that an intercept will appear in the model again. This is not because I want an intercept as it makes the origin and destination coefficients harder to interpret, rather the -1 cheat for removing the intercept only works with one factor level but in double-constrained model we have two factor levels, namely: origins and destinations.


Call:
glm(formula = TRIPS ~ ORIGIN_SZ + DESTIN_SZ + log(DIST), family = poisson(link = "log"), 
    data = inter_zonal_flow, na.action = na.exclude)

Coefficients:
                  Estimate Std. Error   z value Pr(>|z|)    
(Intercept)     21.8312374  0.0059160  3690.190  < 2e-16 ***
ORIGIN_SZAMSZ02  0.5263502  0.0048031   109.585  < 2e-16 ***
ORIGIN_SZAMSZ03  0.3139982  0.0049254    63.751  < 2e-16 ***
ORIGIN_SZAMSZ04 -0.2146257  0.0053639   -40.013  < 2e-16 ***
ORIGIN_SZAMSZ05 -0.1890446  0.0060386   -31.306  < 2e-16 ***
ORIGIN_SZAMSZ06  0.1539201  0.0054401    28.294  < 2e-16 ***
ORIGIN_SZAMSZ07 -0.9826565  0.0098676   -99.584  < 2e-16 ***
ORIGIN_SZAMSZ08 -0.4488417  0.0093070   -48.226  < 2e-16 ***
ORIGIN_SZAMSZ09  0.0713474  0.0057402    12.429  < 2e-16 ***
ORIGIN_SZAMSZ10  0.4313742  0.0050370    85.641  < 2e-16 ***
ORIGIN_SZAMSZ11 -1.4712226  0.0131178  -112.154  < 2e-16 ***
ORIGIN_SZAMSZ12 -1.7250733  0.0111603  -154.573  < 2e-16 ***
ORIGIN_SZBDSZ01  0.8810576  0.0048168   182.914  < 2e-16 ***
ORIGIN_SZBDSZ02  0.1100240  0.0055529    19.814  < 2e-16 ***
ORIGIN_SZBDSZ03  0.3606166  0.0050672    71.167  < 2e-16 ***
ORIGIN_SZBDSZ04  1.4624347  0.0044212   330.781  < 2e-16 ***
ORIGIN_SZBDSZ05  0.6207557  0.0050843   122.092  < 2e-16 ***
ORIGIN_SZBDSZ06  0.6712973  0.0051953   129.214  < 2e-16 ***
ORIGIN_SZBDSZ07 -1.2338669  0.0100775  -122.437  < 2e-16 ***
ORIGIN_SZBDSZ08 -1.0444562  0.0094555  -110.460  < 2e-16 ***
ORIGIN_SZBKSZ01 -0.2838426  0.0071354   -39.780  < 2e-16 ***
ORIGIN_SZBKSZ02  0.5550522  0.0059014    94.054  < 2e-16 ***
ORIGIN_SZBKSZ03  0.7396640  0.0056796   130.231  < 2e-16 ***
ORIGIN_SZBKSZ04 -0.2242451  0.0067482   -33.230  < 2e-16 ***
ORIGIN_SZBKSZ05 -0.2371614  0.0069386   -34.180  < 2e-16 ***
ORIGIN_SZBKSZ06 -0.1413812  0.0065035   -21.739  < 2e-16 ***
ORIGIN_SZBKSZ07  0.7089989  0.0051843   136.758  < 2e-16 ***
ORIGIN_SZBKSZ08 -0.0907065  0.0059157   -15.333  < 2e-16 ***
ORIGIN_SZBKSZ09 -0.1775146  0.0063302   -28.042  < 2e-16 ***
ORIGIN_SZBLSZ01 -2.3684539  0.0154280  -153.516  < 2e-16 ***
ORIGIN_SZBLSZ02 -2.8078475  0.0197839  -141.926  < 2e-16 ***
ORIGIN_SZBLSZ03 -3.3122763  0.0466091   -71.065  < 2e-16 ***
ORIGIN_SZBLSZ04 -2.6770542  0.0241793  -110.717  < 2e-16 ***
ORIGIN_SZBMSZ01  0.0618035  0.0059400    10.405  < 2e-16 ***
ORIGIN_SZBMSZ02 -1.3535767  0.0073741  -183.557  < 2e-16 ***
ORIGIN_SZBMSZ03 -0.7569095  0.0063187  -119.790  < 2e-16 ***
ORIGIN_SZBMSZ04 -0.2949304  0.0059603   -49.483  < 2e-16 ***
ORIGIN_SZBMSZ05 -2.6131992  0.0172376  -151.599  < 2e-16 ***
ORIGIN_SZBMSZ06 -3.0315024  0.0185502  -163.422  < 2e-16 ***
ORIGIN_SZBMSZ07 -0.6962524  0.0064068  -108.674  < 2e-16 ***
ORIGIN_SZBMSZ08 -0.9310730  0.0064541  -144.261  < 2e-16 ***
ORIGIN_SZBMSZ09 -1.2911253  0.0092047  -140.268  < 2e-16 ***
ORIGIN_SZBMSZ10 -1.6687004  0.0095708  -174.353  < 2e-16 ***
ORIGIN_SZBMSZ11 -1.1152794  0.0072027  -154.841  < 2e-16 ***
ORIGIN_SZBMSZ12 -1.5323954  0.0099932  -153.344  < 2e-16 ***
ORIGIN_SZBMSZ13 -0.6267376  0.0065863   -95.158  < 2e-16 ***
ORIGIN_SZBMSZ14 -1.0475467  0.0072472  -144.544  < 2e-16 ***
ORIGIN_SZBMSZ15 -0.5049444  0.0067390   -74.929  < 2e-16 ***
ORIGIN_SZBMSZ16 -1.5282897  0.0099545  -153.527  < 2e-16 ***
ORIGIN_SZBMSZ17 -1.5722349  0.0161533   -97.332  < 2e-16 ***
ORIGIN_SZBPSZ01  0.5814175  0.0062904    92.429  < 2e-16 ***
ORIGIN_SZBPSZ02  0.0875442  0.0072190    12.127  < 2e-16 ***
ORIGIN_SZBPSZ03  0.3358227  0.0070460    47.662  < 2e-16 ***
ORIGIN_SZBPSZ04  0.6507586  0.0057726   112.733  < 2e-16 ***
ORIGIN_SZBPSZ05  0.9502124  0.0052971   179.384  < 2e-16 ***
ORIGIN_SZBPSZ06 -1.0480314  0.0098191  -106.734  < 2e-16 ***
ORIGIN_SZBPSZ07 -0.5467931  0.0091676   -59.644  < 2e-16 ***
ORIGIN_SZBSSZ01  0.2998334  0.0059193    50.654  < 2e-16 ***
ORIGIN_SZBSSZ02  0.2841036  0.0050863    55.856  < 2e-16 ***
ORIGIN_SZBSSZ03 -0.2331505  0.0056565   -41.218  < 2e-16 ***
ORIGIN_SZBTSZ01  0.0987284  0.0063715    15.495  < 2e-16 ***
ORIGIN_SZBTSZ02 -0.6261229  0.0084604   -74.006  < 2e-16 ***
ORIGIN_SZBTSZ03 -0.4326963  0.0073452   -58.909  < 2e-16 ***
ORIGIN_SZBTSZ04 -1.4998668  0.0110013  -136.336  < 2e-16 ***
ORIGIN_SZBTSZ05 -0.9564768  0.0122202   -78.270  < 2e-16 ***
ORIGIN_SZBTSZ06 -1.2853131  0.0099328  -129.401  < 2e-16 ***
ORIGIN_SZBTSZ07 -2.3870991  0.0144589  -165.096  < 2e-16 ***
ORIGIN_SZBTSZ08 -1.3715855  0.0113825  -120.499  < 2e-16 ***
ORIGIN_SZCBSZ01 -3.5940232  0.0548979   -65.467  < 2e-16 ***
ORIGIN_SZCCSZ01 -0.7008220  0.0140373   -49.926  < 2e-16 ***
ORIGIN_SZCHSZ01 -0.9109524  0.0122869   -74.140  < 2e-16 ***
ORIGIN_SZCHSZ02 -0.8566547  0.0088749   -96.526  < 2e-16 ***
ORIGIN_SZCHSZ03  1.1153731  0.0066136   168.650  < 2e-16 ***
ORIGIN_SZCKSZ01  0.3001815  0.0058548    51.271  < 2e-16 ***
ORIGIN_SZCKSZ02  0.7185711  0.0060595   118.585  < 2e-16 ***
ORIGIN_SZCKSZ03  1.1389824  0.0053179   214.178  < 2e-16 ***
ORIGIN_SZCKSZ04  1.6281772  0.0054761   297.324  < 2e-16 ***
ORIGIN_SZCKSZ05  0.8338470  0.0064178   129.927  < 2e-16 ***
ORIGIN_SZCKSZ06  0.6528993  0.0082375    79.259  < 2e-16 ***
ORIGIN_SZCLSZ01 -0.7174758  0.0082123   -87.366  < 2e-16 ***
ORIGIN_SZCLSZ02 -1.7513100  0.0139062  -125.938  < 2e-16 ***
ORIGIN_SZCLSZ03 -1.0362873  0.0085485  -121.224  < 2e-16 ***
ORIGIN_SZCLSZ04  0.6160017  0.0051276   120.136  < 2e-16 ***
ORIGIN_SZCLSZ05 -2.1005122  0.0150228  -139.821  < 2e-16 ***
ORIGIN_SZCLSZ06  0.7252108  0.0049447   146.665  < 2e-16 ***
ORIGIN_SZCLSZ07 -0.5343482  0.0062500   -85.496  < 2e-16 ***
ORIGIN_SZCLSZ08 -0.2153408  0.0067571   -31.869  < 2e-16 ***
ORIGIN_SZCLSZ09 -1.8019961  0.0169078  -106.578  < 2e-16 ***
ORIGIN_SZDTSZ02 -3.9057711  0.0834668   -46.794  < 2e-16 ***
ORIGIN_SZDTSZ03 -3.4152419  0.0738650   -46.236  < 2e-16 ***
ORIGIN_SZDTSZ13 -3.0183438  0.0315257   -95.742  < 2e-16 ***
ORIGIN_SZGLSZ01 -1.7812384  0.0099367  -179.258  < 2e-16 ***
ORIGIN_SZGLSZ02 -0.1074991  0.0054325   -19.788  < 2e-16 ***
ORIGIN_SZGLSZ03 -0.2461106  0.0057176   -43.045  < 2e-16 ***
ORIGIN_SZGLSZ04  0.8657186  0.0046413   186.524  < 2e-16 ***
ORIGIN_SZGLSZ05  0.5871393  0.0047939   122.477  < 2e-16 ***
ORIGIN_SZHGSZ01  0.3543819  0.0050461    70.229  < 2e-16 ***
ORIGIN_SZHGSZ02  0.4218178  0.0050820    83.003  < 2e-16 ***
ORIGIN_SZHGSZ03  0.2411309  0.0054241    44.456  < 2e-16 ***
ORIGIN_SZHGSZ04  0.8180622  0.0046153   177.252  < 2e-16 ***
ORIGIN_SZHGSZ05  1.2173687  0.0045655   266.647  < 2e-16 ***
ORIGIN_SZHGSZ06 -0.1826300  0.0058214   -31.372  < 2e-16 ***
ORIGIN_SZHGSZ07  0.3172839  0.0050733    62.540  < 2e-16 ***
ORIGIN_SZHGSZ08 -0.1151369  0.0057067   -20.176  < 2e-16 ***
ORIGIN_SZHGSZ09 -1.2873441  0.0091690  -140.401  < 2e-16 ***
ORIGIN_SZHGSZ10 -3.3783178  0.0424682   -79.549  < 2e-16 ***
ORIGIN_SZJESZ01  0.4859234  0.0055927    86.885  < 2e-16 ***
ORIGIN_SZJESZ02  0.1766088  0.0055800    31.650  < 2e-16 ***
ORIGIN_SZJESZ03 -0.2177441  0.0059535   -36.574  < 2e-16 ***
ORIGIN_SZJESZ04 -1.5532182  0.0104526  -148.597  < 2e-16 ***
ORIGIN_SZJESZ05 -2.3332926  0.0142701  -163.509  < 2e-16 ***
ORIGIN_SZJESZ06  0.3007382  0.0055019    54.661  < 2e-16 ***
ORIGIN_SZJESZ07 -1.9687994  0.0121092  -162.587  < 2e-16 ***
ORIGIN_SZJESZ08 -1.3032070  0.0122024  -106.800  < 2e-16 ***
ORIGIN_SZJESZ09  0.5762635  0.0058766    98.061  < 2e-16 ***
ORIGIN_SZJESZ10 -1.4423113  0.0194773   -74.051  < 2e-16 ***
ORIGIN_SZJESZ11 -1.9720897  0.0200811   -98.206  < 2e-16 ***
ORIGIN_SZJWSZ01  0.3808627  0.0071357    53.374  < 2e-16 ***
ORIGIN_SZJWSZ02  0.7963999  0.0053150   149.840  < 2e-16 ***
ORIGIN_SZJWSZ03  1.5429636  0.0049961   308.834  < 2e-16 ***
ORIGIN_SZJWSZ04  0.6410760  0.0056711   113.042  < 2e-16 ***
ORIGIN_SZJWSZ05 -2.1571049  0.0133584  -161.479  < 2e-16 ***
ORIGIN_SZJWSZ06 -1.5174532  0.0113384  -133.833  < 2e-16 ***
ORIGIN_SZJWSZ07 -2.7089963  0.0280439   -96.598  < 2e-16 ***
ORIGIN_SZJWSZ08  1.5343415  0.0051711   296.713  < 2e-16 ***
ORIGIN_SZJWSZ09  1.8837410  0.0048845   385.656  < 2e-16 ***
ORIGIN_SZKLSZ01  0.1081286  0.0053307    20.284  < 2e-16 ***
ORIGIN_SZKLSZ02 -0.8844695  0.0067728  -130.591  < 2e-16 ***
ORIGIN_SZKLSZ03 -0.6872640  0.0062857  -109.337  < 2e-16 ***
ORIGIN_SZKLSZ04 -2.2090319  0.0122440  -180.418  < 2e-16 ***
ORIGIN_SZKLSZ05 -1.1728726  0.0110765  -105.888  < 2e-16 ***
ORIGIN_SZKLSZ06 -6.1162315  0.1857789   -32.922  < 2e-16 ***
ORIGIN_SZKLSZ07 -1.4082749  0.0092299  -152.578  < 2e-16 ***
ORIGIN_SZKLSZ08 -1.7781551  0.0104682  -169.862  < 2e-16 ***
ORIGIN_SZLKSZ01 -2.0531568  0.0398803   -51.483  < 2e-16 ***
ORIGIN_SZMDSZ01 -0.8825639  0.0287621   -30.685  < 2e-16 ***
ORIGIN_SZMDSZ02 -0.6219993  0.0107388   -57.921  < 2e-16 ***
ORIGIN_SZMDSZ03 -2.0840156  0.0173117  -120.382  < 2e-16 ***
ORIGIN_SZMPSZ01 -0.9659093  0.0086972  -111.060  < 2e-16 ***
ORIGIN_SZMPSZ02 -1.0411153  0.0073403  -141.836  < 2e-16 ***
ORIGIN_SZMPSZ03  0.0001659  0.0059401     0.028 0.977719    
ORIGIN_SZMUSZ02 -3.7599031  0.1037937   -36.225  < 2e-16 ***
ORIGIN_SZNTSZ01 -3.0388366  0.0355325   -85.523  < 2e-16 ***
ORIGIN_SZNTSZ02 -3.4230640  0.0235902  -145.106  < 2e-16 ***
ORIGIN_SZNTSZ03 -0.9094796  0.0082551  -110.172  < 2e-16 ***
ORIGIN_SZNTSZ05 -4.0861681  0.0499630   -81.784  < 2e-16 ***
ORIGIN_SZNTSZ06 -3.9497128  0.0565388   -69.858  < 2e-16 ***
ORIGIN_SZNVSZ01  0.3235636  0.0049439    65.447  < 2e-16 ***
ORIGIN_SZNVSZ02 -0.6946748  0.0070536   -98.485  < 2e-16 ***
ORIGIN_SZNVSZ03 -1.0540196  0.0083781  -125.806  < 2e-16 ***
ORIGIN_SZNVSZ04 -0.9897977  0.0093463  -105.903  < 2e-16 ***
ORIGIN_SZNVSZ05 -2.2578432  0.0169180  -133.458  < 2e-16 ***
ORIGIN_SZPGSZ01  0.2399827  0.0130436    18.398  < 2e-16 ***
ORIGIN_SZPGSZ02 -0.3352342  0.0078451   -42.732  < 2e-16 ***
ORIGIN_SZPGSZ03  0.9515148  0.0051376   185.207  < 2e-16 ***
ORIGIN_SZPGSZ04  1.3998952  0.0047991   291.697  < 2e-16 ***
ORIGIN_SZPGSZ05  0.4451629  0.0063423    70.189  < 2e-16 ***
ORIGIN_SZPLSZ01 -0.9705918  0.0122781   -79.050  < 2e-16 ***
ORIGIN_SZPLSZ02 -1.0670151  0.0153358   -69.577  < 2e-16 ***
ORIGIN_SZPLSZ03 -2.1229124  0.0373527   -56.834  < 2e-16 ***
ORIGIN_SZPLSZ04 -3.0911932  0.0371296   -83.254  < 2e-16 ***
ORIGIN_SZPLSZ05 -2.1705708  0.0226085   -96.007  < 2e-16 ***
ORIGIN_SZPNSZ01  0.9052637  0.0065952   137.262  < 2e-16 ***
ORIGIN_SZPNSZ02 -0.1720425  0.0125658   -13.691  < 2e-16 ***
ORIGIN_SZPNSZ03 -2.3973459  0.0201408  -119.029  < 2e-16 ***
ORIGIN_SZPNSZ04 -3.4483689  0.0343741  -100.319  < 2e-16 ***
ORIGIN_SZPNSZ05 -2.0588530  0.0282328   -72.924  < 2e-16 ***
ORIGIN_SZPRSZ01 -0.6399015  0.0120470   -53.117  < 2e-16 ***
ORIGIN_SZPRSZ02  0.8122270  0.0050886   159.617  < 2e-16 ***
ORIGIN_SZPRSZ03  0.3990960  0.0051810    77.031  < 2e-16 ***
ORIGIN_SZPRSZ04 -0.8485348  0.0079236  -107.089  < 2e-16 ***
ORIGIN_SZPRSZ05  0.8008791  0.0048532   165.021  < 2e-16 ***
ORIGIN_SZPRSZ06 -1.4498806  0.0121422  -119.408  < 2e-16 ***
ORIGIN_SZPRSZ07 -3.2025045  0.0167118  -191.631  < 2e-16 ***
ORIGIN_SZPRSZ08 -0.5862269  0.0067255   -87.165  < 2e-16 ***
ORIGIN_SZQTSZ01 -0.1859270  0.0075531   -24.616  < 2e-16 ***
ORIGIN_SZQTSZ02 -0.8715122  0.0068124  -127.929  < 2e-16 ***
ORIGIN_SZQTSZ03 -0.1259816  0.0064796   -19.443  < 2e-16 ***
ORIGIN_SZQTSZ04 -1.4620032  0.0079848  -183.098  < 2e-16 ***
ORIGIN_SZQTSZ05 -0.6675643  0.0069616   -95.892  < 2e-16 ***
ORIGIN_SZQTSZ06 -0.8190026  0.0072713  -112.634  < 2e-16 ***
ORIGIN_SZQTSZ07 -1.5189403  0.0099864  -152.101  < 2e-16 ***
ORIGIN_SZQTSZ08 -0.4976238  0.0067874   -73.316  < 2e-16 ***
ORIGIN_SZQTSZ09 -0.9006162  0.0075978  -118.536  < 2e-16 ***
ORIGIN_SZQTSZ10 -0.6690184  0.0071574   -93.473  < 2e-16 ***
ORIGIN_SZQTSZ11 -2.5203437  0.0147000  -171.452  < 2e-16 ***
ORIGIN_SZQTSZ12 -3.0461675  0.0190193  -160.162  < 2e-16 ***
ORIGIN_SZQTSZ13 -0.7501068  0.0084481   -88.791  < 2e-16 ***
ORIGIN_SZQTSZ14 -1.9321849  0.0126114  -153.209  < 2e-16 ***
ORIGIN_SZQTSZ15 -0.9576828  0.0127157   -75.315  < 2e-16 ***
ORIGIN_SZRCSZ01 -1.8167951  0.0129234  -140.582  < 2e-16 ***
ORIGIN_SZRCSZ06 -0.5560563  0.0090507   -61.438  < 2e-16 ***
ORIGIN_SZRVSZ01 -2.8862570  0.0325532   -88.663  < 2e-16 ***
ORIGIN_SZRVSZ02 -3.1555662  0.0281279  -112.186  < 2e-16 ***
ORIGIN_SZRVSZ03 -2.9836089  0.0248449  -120.089  < 2e-16 ***
ORIGIN_SZRVSZ04 -3.5520422  0.0561371   -63.274  < 2e-16 ***
ORIGIN_SZRVSZ05 -2.5866584  0.0180382  -143.399  < 2e-16 ***
ORIGIN_SZSBSZ01  0.2867444  0.0071098    40.331  < 2e-16 ***
ORIGIN_SZSBSZ02 -0.9012334  0.0087262  -103.278  < 2e-16 ***
ORIGIN_SZSBSZ03  0.8311038  0.0055422   149.958  < 2e-16 ***
ORIGIN_SZSBSZ04  0.4044170  0.0062047    65.179  < 2e-16 ***
ORIGIN_SZSBSZ05 -0.2661845  0.0074162   -35.892  < 2e-16 ***
ORIGIN_SZSBSZ06 -0.9023075  0.0175046   -51.547  < 2e-16 ***
ORIGIN_SZSBSZ07  0.0505870  0.0131317     3.852 0.000117 ***
ORIGIN_SZSBSZ08 -1.1158011  0.0145416   -76.732  < 2e-16 ***
ORIGIN_SZSBSZ09 -0.9682835  0.0095396  -101.501  < 2e-16 ***
ORIGIN_SZSESZ02  1.1452735  0.0047810   239.548  < 2e-16 ***
ORIGIN_SZSESZ03  1.2815277  0.0045677   280.564  < 2e-16 ***
ORIGIN_SZSESZ04  0.8085857  0.0052756   153.269  < 2e-16 ***
ORIGIN_SZSESZ05 -0.2329413  0.0063113   -36.909  < 2e-16 ***
ORIGIN_SZSESZ06  1.0576879  0.0049909   211.925  < 2e-16 ***
ORIGIN_SZSESZ07 -2.3165908  0.0196831  -117.695  < 2e-16 ***
ORIGIN_SZSGSZ01 -0.6606350  0.0088079   -75.005  < 2e-16 ***
ORIGIN_SZSGSZ02 -1.3638984  0.0104040  -131.094  < 2e-16 ***
ORIGIN_SZSGSZ03  0.1152591  0.0054649    21.091  < 2e-16 ***
ORIGIN_SZSGSZ04  0.2954067  0.0050865    58.077  < 2e-16 ***
ORIGIN_SZSGSZ05 -2.0792678  0.0109882  -189.227  < 2e-16 ***
ORIGIN_SZSGSZ06  0.4563227  0.0048880    93.356  < 2e-16 ***
ORIGIN_SZSGSZ07 -0.8955254  0.0067100  -133.461  < 2e-16 ***
ORIGIN_SZSKSZ01 -0.3184402  0.0093032   -34.229  < 2e-16 ***
ORIGIN_SZSKSZ02  1.1160484  0.0063851   174.790  < 2e-16 ***
ORIGIN_SZSKSZ03 -0.2566692  0.0086021   -29.838  < 2e-16 ***
ORIGIN_SZSKSZ04 -1.5781827  0.0279394   -56.486  < 2e-16 ***
ORIGIN_SZSKSZ05 -0.2724361  0.0163597   -16.653  < 2e-16 ***
ORIGIN_SZSLSZ01 -2.4458625  0.0330301   -74.050  < 2e-16 ***
ORIGIN_SZSLSZ04 -0.0987076  0.0079626   -12.396  < 2e-16 ***
ORIGIN_SZSRSZ01 -2.2584977  0.0176647  -127.854  < 2e-16 ***
ORIGIN_SZTHSZ01 -2.5878524  0.0489998   -52.814  < 2e-16 ***
ORIGIN_SZTHSZ03 -0.8101746  0.0226814   -35.720  < 2e-16 ***
ORIGIN_SZTHSZ04 -2.4186655  0.0288663   -83.789  < 2e-16 ***
ORIGIN_SZTHSZ06 -1.7080541  0.0186353   -91.657  < 2e-16 ***
ORIGIN_SZTMSZ01 -0.2193476  0.0061823   -35.480  < 2e-16 ***
ORIGIN_SZTMSZ02  1.7772464  0.0043394   409.558  < 2e-16 ***
ORIGIN_SZTMSZ03  1.0051343  0.0046055   218.249  < 2e-16 ***
ORIGIN_SZTMSZ04  0.1642370  0.0055078    29.819  < 2e-16 ***
ORIGIN_SZTMSZ05 -1.2878706  0.0114828  -112.157  < 2e-16 ***
ORIGIN_SZTNSZ01 -1.7163504  0.0131268  -130.751  < 2e-16 ***
ORIGIN_SZTNSZ02 -1.6508988  0.0103851  -158.968  < 2e-16 ***
ORIGIN_SZTNSZ03 -2.1545577  0.0137947  -156.187  < 2e-16 ***
ORIGIN_SZTNSZ04 -0.3949120  0.0078496   -50.310  < 2e-16 ***
ORIGIN_SZTPSZ01 -0.8058100  0.0069916  -115.253  < 2e-16 ***
ORIGIN_SZTPSZ02  0.5369060  0.0047272   113.577  < 2e-16 ***
ORIGIN_SZTPSZ03 -0.7779333  0.0064278  -121.027  < 2e-16 ***
ORIGIN_SZTPSZ04 -0.8153581  0.0061387  -132.823  < 2e-16 ***
ORIGIN_SZTPSZ05 -0.5073676  0.0067771   -74.865  < 2e-16 ***
ORIGIN_SZTPSZ06  0.0847301  0.0065717    12.893  < 2e-16 ***
ORIGIN_SZTPSZ07 -0.5839519  0.0066148   -88.280  < 2e-16 ***
ORIGIN_SZTPSZ08 -1.0577941  0.0098480  -107.412  < 2e-16 ***
ORIGIN_SZTPSZ09 -0.9067707  0.0071367  -127.057  < 2e-16 ***
ORIGIN_SZTPSZ10 -1.1362091  0.0080905  -140.438  < 2e-16 ***
ORIGIN_SZTPSZ11 -0.2374621  0.0059472   -39.928  < 2e-16 ***
ORIGIN_SZTPSZ12 -0.8028874  0.0069663  -115.253  < 2e-16 ***
ORIGIN_SZTSSZ01 -2.7809271  0.0482843   -57.595  < 2e-16 ***
ORIGIN_SZTSSZ02  0.0425804  0.0105088     4.052 5.08e-05 ***
ORIGIN_SZTSSZ03  0.1142369  0.0109412    10.441  < 2e-16 ***
ORIGIN_SZTSSZ04 -0.6186261  0.0116324   -53.181  < 2e-16 ***
ORIGIN_SZTSSZ05 -1.0846732  0.0173555   -62.497  < 2e-16 ***
ORIGIN_SZTSSZ06  0.3980173  0.0198100    20.092  < 2e-16 ***
ORIGIN_SZWCSZ01  1.3545143  0.0092002   147.227  < 2e-16 ***
ORIGIN_SZWCSZ02 -2.9863278  0.0330906   -90.247  < 2e-16 ***
ORIGIN_SZWCSZ03 -5.0504916  0.1241385   -40.684  < 2e-16 ***
ORIGIN_SZWDSZ01  1.5238429  0.0049404   308.448  < 2e-16 ***
ORIGIN_SZWDSZ02  0.2832576  0.0056218    50.386  < 2e-16 ***
ORIGIN_SZWDSZ03  1.3702524  0.0053266   257.245  < 2e-16 ***
ORIGIN_SZWDSZ04  1.0248225  0.0059272   172.903  < 2e-16 ***
ORIGIN_SZWDSZ05  0.2356778  0.0060587    38.899  < 2e-16 ***
ORIGIN_SZWDSZ06  0.3146925  0.0059919    52.520  < 2e-16 ***
ORIGIN_SZWDSZ07 -1.4971897  0.0091243  -164.088  < 2e-16 ***
ORIGIN_SZWDSZ08 -0.8894079  0.0087414  -101.747  < 2e-16 ***
ORIGIN_SZWDSZ09  1.4437633  0.0053160   271.590  < 2e-16 ***
ORIGIN_SZYSSZ01 -0.2519398  0.0064443   -39.095  < 2e-16 ***
ORIGIN_SZYSSZ02  0.8726785  0.0057658   151.354  < 2e-16 ***
ORIGIN_SZYSSZ03  1.7868139  0.0050674   352.611  < 2e-16 ***
ORIGIN_SZYSSZ04  0.8418040  0.0051738   162.704  < 2e-16 ***
ORIGIN_SZYSSZ05  0.4292096  0.0062520    68.652  < 2e-16 ***
ORIGIN_SZYSSZ06 -0.7459961  0.0119123   -62.624  < 2e-16 ***
ORIGIN_SZYSSZ07 -0.8422281  0.0144559   -58.262  < 2e-16 ***
ORIGIN_SZYSSZ08  0.1829428  0.0067885    26.949  < 2e-16 ***
ORIGIN_SZYSSZ09  1.1159712  0.0050760   219.853  < 2e-16 ***
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DESTIN_SZAMSZ03  0.0760100  0.0044639    17.028  < 2e-16 ***
DESTIN_SZAMSZ04 -1.1306391  0.0064373  -175.639  < 2e-16 ***
DESTIN_SZAMSZ05 -1.0751133  0.0065164  -164.985  < 2e-16 ***
DESTIN_SZAMSZ06 -0.9624298  0.0065937  -145.962  < 2e-16 ***
DESTIN_SZAMSZ07 -1.5060319  0.0097616  -154.281  < 2e-16 ***
DESTIN_SZAMSZ08 -0.4813202  0.0069794   -68.963  < 2e-16 ***
DESTIN_SZAMSZ09 -1.0220675  0.0066313  -154.129  < 2e-16 ***
DESTIN_SZAMSZ10  0.1235142  0.0047044    26.255  < 2e-16 ***
DESTIN_SZAMSZ11 -0.8917993  0.0088519  -100.746  < 2e-16 ***
DESTIN_SZAMSZ12  0.0195208  0.0051704     3.775 0.000160 ***
DESTIN_SZBDSZ01  0.9736349  0.0042757   227.713  < 2e-16 ***
DESTIN_SZBDSZ02 -0.1969470  0.0055284   -35.625  < 2e-16 ***
DESTIN_SZBDSZ03  0.1266471  0.0050786    24.938  < 2e-16 ***
DESTIN_SZBDSZ04  1.1608485  0.0041956   276.684  < 2e-16 ***
DESTIN_SZBDSZ05  0.9293840  0.0044412   209.265  < 2e-16 ***
DESTIN_SZBDSZ06  0.4090567  0.0050300    81.323  < 2e-16 ***
DESTIN_SZBDSZ07 -0.8171478  0.0098945   -82.586  < 2e-16 ***
DESTIN_SZBDSZ08 -1.5895287  0.0111632  -142.391  < 2e-16 ***
DESTIN_SZBKSZ01 -1.3793311  0.0072145  -191.189  < 2e-16 ***
DESTIN_SZBKSZ02 -0.5253670  0.0061879   -84.903  < 2e-16 ***
DESTIN_SZBKSZ03 -1.0095362  0.0065426  -154.301  < 2e-16 ***
DESTIN_SZBKSZ04 -0.5662858  0.0056453  -100.311  < 2e-16 ***
DESTIN_SZBKSZ05 -0.9406607  0.0070597  -133.244  < 2e-16 ***
DESTIN_SZBKSZ06 -1.3129276  0.0067414  -194.755  < 2e-16 ***
DESTIN_SZBKSZ07  0.0120605  0.0049284     2.447 0.014400 *  
DESTIN_SZBKSZ08 -1.3658471  0.0075109  -181.849  < 2e-16 ***
DESTIN_SZBKSZ09 -0.1771310  0.0055645   -31.832  < 2e-16 ***
DESTIN_SZBLSZ01 -0.8175223  0.0075645  -108.074  < 2e-16 ***
DESTIN_SZBLSZ02  0.1631280  0.0071753    22.735  < 2e-16 ***
DESTIN_SZBLSZ03  1.2598494  0.0081706   154.194  < 2e-16 ***
DESTIN_SZBLSZ04 -0.5642975  0.0137827   -40.943  < 2e-16 ***
DESTIN_SZBMSZ01  0.6921844  0.0054211   127.684  < 2e-16 ***
DESTIN_SZBMSZ02 -0.1209392  0.0055362   -21.845  < 2e-16 ***
DESTIN_SZBMSZ03 -0.2373881  0.0062427   -38.027  < 2e-16 ***
DESTIN_SZBMSZ04 -0.0407117  0.0058001    -7.019 2.23e-12 ***
DESTIN_SZBMSZ05 -0.2363309  0.0075967   -31.110  < 2e-16 ***
DESTIN_SZBMSZ06 -1.1930710  0.0134761   -88.532  < 2e-16 ***
DESTIN_SZBMSZ07  0.4625103  0.0051864    89.178  < 2e-16 ***
DESTIN_SZBMSZ08 -0.8604731  0.0069899  -123.102  < 2e-16 ***
DESTIN_SZBMSZ09 -2.1290239  0.0154841  -137.498  < 2e-16 ***
DESTIN_SZBMSZ10 -1.4617153  0.0094014  -155.478  < 2e-16 ***
DESTIN_SZBMSZ11 -1.3234050  0.0085506  -154.773  < 2e-16 ***
DESTIN_SZBMSZ12 -0.8399230  0.0085361   -98.397  < 2e-16 ***
DESTIN_SZBMSZ13  0.1366529  0.0059697    22.891  < 2e-16 ***
DESTIN_SZBMSZ14 -1.0491968  0.0083021  -126.378  < 2e-16 ***
DESTIN_SZBMSZ15 -0.6726684  0.0076276   -88.189  < 2e-16 ***
DESTIN_SZBMSZ16 -1.4011734  0.0116569  -120.201  < 2e-16 ***
DESTIN_SZBMSZ17 -1.5682752  0.0167333   -93.722  < 2e-16 ***
DESTIN_SZBPSZ01 -1.1120017  0.0063197  -175.959  < 2e-16 ***
DESTIN_SZBPSZ02 -2.0833466  0.0091139  -228.590  < 2e-16 ***
DESTIN_SZBPSZ03 -1.6937265  0.0087437  -193.709  < 2e-16 ***
DESTIN_SZBPSZ04 -0.7964999  0.0066129  -120.447  < 2e-16 ***
DESTIN_SZBPSZ05  0.2109118  0.0048815    43.206  < 2e-16 ***
DESTIN_SZBPSZ06 -1.1808365  0.0083657  -141.152  < 2e-16 ***
DESTIN_SZBPSZ07 -0.2077428  0.0084543   -24.572  < 2e-16 ***
DESTIN_SZBSSZ01  0.3164175  0.0050682    62.431  < 2e-16 ***
DESTIN_SZBSSZ02 -0.4852688  0.0057001   -85.134  < 2e-16 ***
DESTIN_SZBSSZ03  0.4130432  0.0043061    95.921  < 2e-16 ***
DESTIN_SZBTSZ01  0.6215095  0.0048914   127.061  < 2e-16 ***
DESTIN_SZBTSZ02 -0.0145076  0.0071799    -2.021 0.043324 *  
DESTIN_SZBTSZ03  0.4919981  0.0058498    84.105  < 2e-16 ***
DESTIN_SZBTSZ04 -0.6957555  0.0114078   -60.989  < 2e-16 ***
DESTIN_SZBTSZ05  0.3329814  0.0073568    45.262  < 2e-16 ***
DESTIN_SZBTSZ06 -0.1333295  0.0073965   -18.026  < 2e-16 ***
DESTIN_SZBTSZ07 -1.4449581  0.0113186  -127.663  < 2e-16 ***
DESTIN_SZBTSZ08 -0.7079056  0.0103797   -68.201  < 2e-16 ***
DESTIN_SZCBSZ01 -5.7344725  0.3162767   -18.131  < 2e-16 ***
DESTIN_SZCCSZ01 -0.0009541  0.0083381    -0.114 0.908900    
DESTIN_SZCHSZ01 -0.2083016  0.0099054   -21.029  < 2e-16 ***
DESTIN_SZCHSZ02  0.5369606  0.0057531    93.334  < 2e-16 ***
DESTIN_SZCHSZ03  2.5530638  0.0043945   580.971  < 2e-16 ***
DESTIN_SZCKSZ01 -0.5725975  0.0056507  -101.333  < 2e-16 ***
DESTIN_SZCKSZ02 -1.1181852  0.0063287  -176.685  < 2e-16 ***
DESTIN_SZCKSZ03  0.1156680  0.0049440    23.396  < 2e-16 ***
DESTIN_SZCKSZ04 -0.8647725  0.0071003  -121.794  < 2e-16 ***
DESTIN_SZCKSZ05 -1.1641791  0.0076248  -152.684  < 2e-16 ***
DESTIN_SZCKSZ06 -0.4397612  0.0073040   -60.208  < 2e-16 ***
DESTIN_SZCLSZ01  0.1930552  0.0053752    35.916  < 2e-16 ***
DESTIN_SZCLSZ02 -2.0436501  0.0136039  -150.225  < 2e-16 ***
DESTIN_SZCLSZ03 -0.9338571  0.0082908  -112.638  < 2e-16 ***
DESTIN_SZCLSZ04  0.0532041  0.0053276     9.987  < 2e-16 ***
DESTIN_SZCLSZ05 -1.0782781  0.0088184  -122.276  < 2e-16 ***
DESTIN_SZCLSZ06  0.4068171  0.0049068    82.910  < 2e-16 ***
DESTIN_SZCLSZ07 -0.3579507  0.0060289   -59.373  < 2e-16 ***
DESTIN_SZCLSZ08 -0.2487993  0.0066588   -37.364  < 2e-16 ***
DESTIN_SZCLSZ09  0.1611080  0.0071178    22.635  < 2e-16 ***
DESTIN_SZDTSZ02 -1.7308348  0.0349466   -49.528  < 2e-16 ***
DESTIN_SZDTSZ03 -0.5994253  0.0146230   -40.992  < 2e-16 ***
DESTIN_SZDTSZ13 -1.3685031  0.0162803   -84.059  < 2e-16 ***
DESTIN_SZGLSZ01 -0.0910001  0.0055275   -16.463  < 2e-16 ***
DESTIN_SZGLSZ02 -0.0692224  0.0052840   -13.100  < 2e-16 ***
DESTIN_SZGLSZ03  0.6493421  0.0043446   149.459  < 2e-16 ***
DESTIN_SZGLSZ04  0.9327947  0.0043674   213.583  < 2e-16 ***
DESTIN_SZGLSZ05  0.8161728  0.0043625   187.087  < 2e-16 ***
DESTIN_SZHGSZ01  0.0658625  0.0042516    15.491  < 2e-16 ***
DESTIN_SZHGSZ02 -0.8134329  0.0056721  -143.409  < 2e-16 ***
DESTIN_SZHGSZ03 -1.3546132  0.0066257  -204.448  < 2e-16 ***
DESTIN_SZHGSZ04 -0.4500588  0.0048448   -92.895  < 2e-16 ***
DESTIN_SZHGSZ05 -0.5026431  0.0050996   -98.566  < 2e-16 ***
DESTIN_SZHGSZ06 -0.8673686  0.0059530  -145.704  < 2e-16 ***
DESTIN_SZHGSZ07  0.0560490  0.0047702    11.750  < 2e-16 ***
DESTIN_SZHGSZ08 -0.0443189  0.0052599    -8.426  < 2e-16 ***
DESTIN_SZHGSZ09 -0.0126355  0.0054966    -2.299 0.021518 *  
DESTIN_SZHGSZ10 -3.5821793  0.0263281  -136.059  < 2e-16 ***
DESTIN_SZJESZ01 -0.3704281  0.0056684   -65.350  < 2e-16 ***
DESTIN_SZJESZ02 -0.7369159  0.0058686  -125.570  < 2e-16 ***
DESTIN_SZJESZ03 -0.8985484  0.0063627  -141.222  < 2e-16 ***
DESTIN_SZJESZ04 -1.0511995  0.0073996  -142.061  < 2e-16 ***
DESTIN_SZJESZ05 -1.5324974  0.0102612  -149.349  < 2e-16 ***
DESTIN_SZJESZ06  0.3105267  0.0048241    64.370  < 2e-16 ***
DESTIN_SZJESZ07 -1.3234483  0.0085497  -154.795  < 2e-16 ***
DESTIN_SZJESZ08 -0.6559742  0.0083174   -78.867  < 2e-16 ***
DESTIN_SZJESZ09  0.2663752  0.0063370    42.035  < 2e-16 ***
DESTIN_SZJESZ10  0.8529026  0.0076067   112.126  < 2e-16 ***
DESTIN_SZJESZ11  0.5559641  0.0074629    74.497  < 2e-16 ***
DESTIN_SZJWSZ01 -0.9790971  0.0071830  -136.308  < 2e-16 ***
DESTIN_SZJWSZ02 -0.8746590  0.0060179  -145.342  < 2e-16 ***
DESTIN_SZJWSZ03  0.5689062  0.0049105   115.855  < 2e-16 ***
DESTIN_SZJWSZ04  0.4520963  0.0050302    89.876  < 2e-16 ***
DESTIN_SZJWSZ05 -1.0249671  0.0067371  -152.137  < 2e-16 ***
DESTIN_SZJWSZ06 -0.7451483  0.0062189  -119.819  < 2e-16 ***
DESTIN_SZJWSZ07 -2.8453099  0.0287335   -99.024  < 2e-16 ***
DESTIN_SZJWSZ08 -0.3372309  0.0058003   -58.141  < 2e-16 ***
DESTIN_SZJWSZ09  1.0505330  0.0045908   228.832  < 2e-16 ***
DESTIN_SZKLSZ01 -0.2334836  0.0057970   -40.277  < 2e-16 ***
DESTIN_SZKLSZ02 -0.5416148  0.0061432   -88.164  < 2e-16 ***
DESTIN_SZKLSZ03 -0.8026495  0.0068745  -116.757  < 2e-16 ***
DESTIN_SZKLSZ04 -1.2918594  0.0090197  -143.227  < 2e-16 ***
DESTIN_SZKLSZ05 -0.4069101  0.0087812   -46.339  < 2e-16 ***
DESTIN_SZKLSZ06 -2.5333101  0.0363215   -69.747  < 2e-16 ***
DESTIN_SZKLSZ07 -0.6623343  0.0070761   -93.601  < 2e-16 ***
DESTIN_SZKLSZ08 -0.1408205  0.0054965   -25.620  < 2e-16 ***
DESTIN_SZLKSZ01 -1.2639235  0.0208254   -60.691  < 2e-16 ***
DESTIN_SZMDSZ01 -1.5655800  0.0202787   -77.203  < 2e-16 ***
DESTIN_SZMDSZ02 -0.9767682  0.0114687   -85.168  < 2e-16 ***
DESTIN_SZMDSZ03 -3.3328109  0.0254294  -131.061  < 2e-16 ***
DESTIN_SZMPSZ01 -0.4552859  0.0080666   -56.441  < 2e-16 ***
DESTIN_SZMPSZ02 -0.5386560  0.0064620   -83.358  < 2e-16 ***
DESTIN_SZMPSZ03  0.4952000  0.0052295    94.694  < 2e-16 ***
DESTIN_SZMUSZ02 -1.4434175  0.0202509   -71.277  < 2e-16 ***
DESTIN_SZNTSZ01 -2.9194067  0.0449654   -64.926  < 2e-16 ***
DESTIN_SZNTSZ02 -1.3780179  0.0112867  -122.092  < 2e-16 ***
DESTIN_SZNTSZ03 -0.5044699  0.0080449   -62.707  < 2e-16 ***
DESTIN_SZNTSZ05 -2.0017134  0.0258750   -77.361  < 2e-16 ***
DESTIN_SZNTSZ06 -3.8120537  0.0434271   -87.781  < 2e-16 ***
DESTIN_SZNVSZ01 -0.1071506  0.0051026   -20.999  < 2e-16 ***
DESTIN_SZNVSZ02 -0.0274710  0.0057611    -4.768 1.86e-06 ***
DESTIN_SZNVSZ03  0.1076352  0.0057909    18.587  < 2e-16 ***
DESTIN_SZNVSZ04 -1.2087250  0.0110438  -109.448  < 2e-16 ***
DESTIN_SZNVSZ05 -1.0058290  0.0092167  -109.131  < 2e-16 ***
DESTIN_SZPGSZ01 -1.2029931  0.0163170   -73.726  < 2e-16 ***
DESTIN_SZPGSZ02 -1.2878671  0.0074139  -173.709  < 2e-16 ***
DESTIN_SZPGSZ03 -0.1520894  0.0048629   -31.275  < 2e-16 ***
DESTIN_SZPGSZ04 -0.1985959  0.0050374   -39.424  < 2e-16 ***
DESTIN_SZPGSZ05 -1.5290983  0.0082617  -185.083  < 2e-16 ***
DESTIN_SZPLSZ01 -0.3567934  0.0074298   -48.022  < 2e-16 ***
DESTIN_SZPLSZ02 -1.7114351  0.0134462  -127.280  < 2e-16 ***
DESTIN_SZPLSZ03 -0.3241427  0.0098895   -32.776  < 2e-16 ***
DESTIN_SZPLSZ04 -1.7117196  0.0119003  -143.838  < 2e-16 ***
DESTIN_SZPLSZ05 -0.5086379  0.0120051   -42.368  < 2e-16 ***
DESTIN_SZPNSZ01  0.2026781  0.0068977    29.383  < 2e-16 ***
DESTIN_SZPNSZ02  0.8313754  0.0078544   105.848  < 2e-16 ***
DESTIN_SZPNSZ03 -0.4041254  0.0086586   -46.673  < 2e-16 ***
DESTIN_SZPNSZ04  1.5814539  0.0093641   168.885  < 2e-16 ***
DESTIN_SZPNSZ05  1.1823430  0.0129843    91.059  < 2e-16 ***
DESTIN_SZPRSZ01 -1.1057553  0.0088197  -125.374  < 2e-16 ***
DESTIN_SZPRSZ02  0.0895099  0.0056308    15.897  < 2e-16 ***
DESTIN_SZPRSZ03  0.6921925  0.0043977   157.397  < 2e-16 ***
DESTIN_SZPRSZ04 -0.2848336  0.0084725   -33.619  < 2e-16 ***
DESTIN_SZPRSZ05  0.1744480  0.0053553    32.575  < 2e-16 ***
DESTIN_SZPRSZ06  0.4279206  0.0058735    72.856  < 2e-16 ***
DESTIN_SZPRSZ07 -1.5123108  0.0124303  -121.664  < 2e-16 ***
DESTIN_SZPRSZ08 -0.5650226  0.0068530   -82.449  < 2e-16 ***
DESTIN_SZQTSZ01 -0.5952360  0.0090505   -65.769  < 2e-16 ***
DESTIN_SZQTSZ02 -0.7728170  0.0078910   -97.937  < 2e-16 ***
DESTIN_SZQTSZ03 -0.5066812  0.0073996   -68.474  < 2e-16 ***
DESTIN_SZQTSZ04 -0.6398414  0.0075411   -84.847  < 2e-16 ***
DESTIN_SZQTSZ05 -0.4354527  0.0069345   -62.795  < 2e-16 ***
DESTIN_SZQTSZ06 -0.6597391  0.0071919   -91.733  < 2e-16 ***
DESTIN_SZQTSZ07 -0.9392696  0.0112518   -83.477  < 2e-16 ***
DESTIN_SZQTSZ08  0.4617774  0.0057011    80.998  < 2e-16 ***
DESTIN_SZQTSZ09 -0.3174497  0.0065890   -48.178  < 2e-16 ***
DESTIN_SZQTSZ10  0.1993449  0.0059923    33.267  < 2e-16 ***
DESTIN_SZQTSZ11  0.2551535  0.0061885    41.230  < 2e-16 ***
DESTIN_SZQTSZ12 -0.1662603  0.0086701   -19.176  < 2e-16 ***
DESTIN_SZQTSZ13  0.5500978  0.0063091    87.192  < 2e-16 ***
DESTIN_SZQTSZ14  0.5364435  0.0070157    76.463  < 2e-16 ***
DESTIN_SZQTSZ15  1.3611043  0.0081643   166.715  < 2e-16 ***
DESTIN_SZRCSZ01 -0.1034049  0.0076769   -13.470  < 2e-16 ***
DESTIN_SZRCSZ06 -1.0633902  0.0189846   -56.013  < 2e-16 ***
DESTIN_SZRVSZ01 -1.5486221  0.0165272   -93.701  < 2e-16 ***
DESTIN_SZRVSZ02 -2.4092611  0.0326906   -73.699  < 2e-16 ***
DESTIN_SZRVSZ03 -1.5172079  0.0139258  -108.950  < 2e-16 ***
DESTIN_SZRVSZ04 -1.1663615  0.0157430   -74.088  < 2e-16 ***
DESTIN_SZRVSZ05 -2.2404292  0.0281339   -79.634  < 2e-16 ***
DESTIN_SZSBSZ01 -1.3783780  0.0096022  -143.549  < 2e-16 ***
DESTIN_SZSBSZ02 -1.4445213  0.0081630  -176.959  < 2e-16 ***
DESTIN_SZSBSZ03  0.5149906  0.0051663    99.683  < 2e-16 ***
DESTIN_SZSBSZ04  0.2389086  0.0060765    39.317  < 2e-16 ***
DESTIN_SZSBSZ05 -1.2737442  0.0082818  -153.801  < 2e-16 ***
DESTIN_SZSBSZ06 -1.8683520  0.0227277   -82.206  < 2e-16 ***
DESTIN_SZSBSZ07 -0.5993154  0.0184895   -32.414  < 2e-16 ***
DESTIN_SZSBSZ08  0.8156302  0.0059840   136.302  < 2e-16 ***
DESTIN_SZSBSZ09  0.0900611  0.0057054    15.785  < 2e-16 ***
DESTIN_SZSESZ02 -0.6397704  0.0052491  -121.882  < 2e-16 ***
DESTIN_SZSESZ03  0.1714103  0.0042357    40.468  < 2e-16 ***
DESTIN_SZSESZ04 -1.0596175  0.0059865  -177.002  < 2e-16 ***
DESTIN_SZSESZ05 -0.8071891  0.0051229  -157.566  < 2e-16 ***
DESTIN_SZSESZ06 -0.5580934  0.0066216   -84.284  < 2e-16 ***
DESTIN_SZSESZ07 -3.1448863  0.0227788  -138.062  < 2e-16 ***
DESTIN_SZSGSZ01 -0.1795225  0.0060127   -29.857  < 2e-16 ***
DESTIN_SZSGSZ02 -0.2986570  0.0053561   -55.760  < 2e-16 ***
DESTIN_SZSGSZ03 -0.4074671  0.0050609   -80.513  < 2e-16 ***
DESTIN_SZSGSZ04 -0.1505164  0.0050931   -29.553  < 2e-16 ***
DESTIN_SZSGSZ05 -1.9908372  0.0101448  -196.242  < 2e-16 ***
DESTIN_SZSGSZ06  0.6715268  0.0041161   163.148  < 2e-16 ***
DESTIN_SZSGSZ07 -0.4494757  0.0055319   -81.252  < 2e-16 ***
DESTIN_SZSISZ01 -0.5517983  0.0261860   -21.072  < 2e-16 ***
DESTIN_SZSKSZ01 -0.4749154  0.0079257   -59.921  < 2e-16 ***
DESTIN_SZSKSZ02  0.9400302  0.0057218   164.290  < 2e-16 ***
DESTIN_SZSKSZ03 -0.2800377  0.0066081   -42.378  < 2e-16 ***
DESTIN_SZSKSZ04 -1.2570212  0.0145351   -86.482  < 2e-16 ***
DESTIN_SZSKSZ05 -0.2600474  0.0112800   -23.054  < 2e-16 ***
DESTIN_SZSLSZ01 -0.7775604  0.0085818   -90.606  < 2e-16 ***
DESTIN_SZSLSZ04 -0.8586515  0.0073142  -117.396  < 2e-16 ***
DESTIN_SZSRSZ01 -1.1370887  0.0142148   -79.993  < 2e-16 ***
DESTIN_SZTHSZ01 -4.3259988  0.0368554  -117.378  < 2e-16 ***
DESTIN_SZTHSZ03 -2.6632914  0.0252720  -105.385  < 2e-16 ***
DESTIN_SZTHSZ04 -3.1000906  0.0216372  -143.276  < 2e-16 ***
DESTIN_SZTHSZ06 -2.5952642  0.0156340  -166.001  < 2e-16 ***
DESTIN_SZTMSZ01 -0.2092828  0.0059257   -35.318  < 2e-16 ***
DESTIN_SZTMSZ02  1.8238139  0.0039155   465.798  < 2e-16 ***
DESTIN_SZTMSZ03  0.8518259  0.0043636   195.210  < 2e-16 ***
DESTIN_SZTMSZ04  1.0222812  0.0043466   235.191  < 2e-16 ***
DESTIN_SZTMSZ05  0.6323777  0.0060058   105.294  < 2e-16 ***
DESTIN_SZTNSZ01 -0.3336078  0.0074388   -44.847  < 2e-16 ***
DESTIN_SZTNSZ02 -1.0820469  0.0101689  -106.408  < 2e-16 ***
DESTIN_SZTNSZ03 -1.4186505  0.0119906  -118.313  < 2e-16 ***
DESTIN_SZTNSZ04 -0.3058199  0.0074743   -40.916  < 2e-16 ***
DESTIN_SZTPSZ01 -0.4872299  0.0061571   -79.133  < 2e-16 ***
DESTIN_SZTPSZ02  0.7158441  0.0041312   173.278  < 2e-16 ***
DESTIN_SZTPSZ03 -0.4314229  0.0059917   -72.004  < 2e-16 ***
DESTIN_SZTPSZ04 -1.5898245  0.0076083  -208.959  < 2e-16 ***
DESTIN_SZTPSZ05 -1.0445550  0.0062363  -167.497  < 2e-16 ***
DESTIN_SZTPSZ06 -0.4319582  0.0070100   -61.621  < 2e-16 ***
DESTIN_SZTPSZ07 -2.1602303  0.0120352  -179.493  < 2e-16 ***
DESTIN_SZTPSZ08 -1.1920493  0.0093083  -128.063  < 2e-16 ***
DESTIN_SZTPSZ09 -0.2022481  0.0071137   -28.431  < 2e-16 ***
DESTIN_SZTPSZ10 -1.2464793  0.0090124  -138.308  < 2e-16 ***
DESTIN_SZTPSZ11 -0.0808445  0.0056019   -14.432  < 2e-16 ***
DESTIN_SZTPSZ12 -0.6784376  0.0066340  -102.267  < 2e-16 ***
DESTIN_SZTSSZ01 -1.5845062  0.0222086   -71.346  < 2e-16 ***
DESTIN_SZTSSZ02 -0.1886010  0.0146338   -12.888  < 2e-16 ***
DESTIN_SZTSSZ03  0.6525526  0.0092450    70.585  < 2e-16 ***
DESTIN_SZTSSZ04  0.5285464  0.0100182    52.759  < 2e-16 ***
DESTIN_SZTSSZ05  1.4670106  0.0104357   140.577  < 2e-16 ***
DESTIN_SZTSSZ06  2.5043588  0.0167444   149.564  < 2e-16 ***
DESTIN_SZWCSZ01  1.9787931  0.0054306   364.375  < 2e-16 ***
DESTIN_SZWCSZ02 -2.2593108  0.0127916  -176.624  < 2e-16 ***
DESTIN_SZWCSZ03 -3.1897655  0.0326927   -97.568  < 2e-16 ***
DESTIN_SZWDSZ01  1.0476108  0.0044629   234.738  < 2e-16 ***
DESTIN_SZWDSZ02 -1.3176990  0.0065894  -199.973  < 2e-16 ***
DESTIN_SZWDSZ03  0.3432057  0.0052496    65.377  < 2e-16 ***
DESTIN_SZWDSZ04 -0.7895927  0.0073392  -107.586  < 2e-16 ***
DESTIN_SZWDSZ05 -0.8751665  0.0072946  -119.975  < 2e-16 ***
DESTIN_SZWDSZ06 -0.2106221  0.0053027   -39.720  < 2e-16 ***
DESTIN_SZWDSZ07 -1.6050834  0.0071754  -223.692  < 2e-16 ***
DESTIN_SZWDSZ08 -0.5124717  0.0069223   -74.032  < 2e-16 ***
DESTIN_SZWDSZ09  0.3813542  0.0054697    69.721  < 2e-16 ***
DESTIN_SZYSSZ01  0.0853753  0.0046572    18.332  < 2e-16 ***
DESTIN_SZYSSZ02 -0.3227172  0.0057351   -56.271  < 2e-16 ***
DESTIN_SZYSSZ03 -0.4151283  0.0066299   -62.615  < 2e-16 ***
DESTIN_SZYSSZ04 -0.4637327  0.0058206   -79.671  < 2e-16 ***
DESTIN_SZYSSZ05 -1.5888242  0.0111001  -143.136  < 2e-16 ***
DESTIN_SZYSSZ06 -1.4606209  0.0107759  -135.545  < 2e-16 ***
DESTIN_SZYSSZ07 -0.7839065  0.0144357   -54.304  < 2e-16 ***
DESTIN_SZYSSZ08  0.6265412  0.0045504   137.691  < 2e-16 ***
DESTIN_SZYSSZ09  0.1520067  0.0048092    31.607  < 2e-16 ***
log(DIST)       -1.8468315  0.0004608 -4008.033  < 2e-16 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

(Dispersion parameter for poisson family taken to be 1)

    Null deviance: 47094011  on 14470  degrees of freedom
Residual deviance: 10420261  on 13912  degrees of freedom
AIC: 10510518

Number of Fisher Scoring iterations: 7
Do it yourself

What statistical conclusion you can draw from the report above?

Next, let us examine how well the proportion of variance in the dependent variable (i.e. TRIPS) that can be explained by the explanatory variables.

Do it yourself

Using the R-Squared function written earlier, compute the R-Squared of the Doubly-constrined Model.

Show the code chunk
CalcRSquared(dbcSIM_Poisson$data$TRIPS,
             dbcSIM_Poisson$fitted.values)
[1] 0.7001882

Notice that there is a relatively greater improvement in the R-Squared value.

Model comparison

Statistical measures

Another useful model performance measure for continuous dependent variable is Root Mean Squared Error. In this sub-section, you will learn how to use compare_performance() of performance package

First of all, let us create a list called model_list by using the code chunk below.

model_list <- list(
  Origin_Constrained = orcSIM_Poisson,
  Doubly_Constrained = dbcSIM_Poisson)

Next, we will compute the RMSE of all the models in model_list file by using the code chunk below.

compare_performance(model_list,
                    metrics = "RMSE")
# Comparison of Model Performance Indices

Name               | Model |     RMSE
-------------------------------------
Origin_Constrained |   glm | 2613.236
Doubly_Constrained |   glm | 1906.694

The print above reveals that doubly constrained SIM is the best model among the two SIMs because it has the smallest RMSE value of 1906.694.

Visualising fitted values

In this section, you will learn how to visualise the observed values and the fitted values.

Firstly we will extract the fitted values from Origin-constrained Model by using the code chunk below.

df <- as.data.frame(orcSIM_Poisson$fitted.values) %>%
  round(digits = 0)

Next, we will append the fitted values into inter_zonal_flow data frame by using the code chunk below.

inter_zonal_flow <- inter_zonal_flow %>%
  cbind(df) %>%
  rename(orcTRIPS = "orcSIM_Poisson.fitted.values")
Tip

Notice that rename() is used to rename the field name and the $ in the original field name has been replaced with an .. This is because R replaced $ with . during the cbind().

Do it yourself

Repeat the same step for Doubly Constrained Model (i.e. dbcSIM_Poisson)

Show the code chunk
df <- as.data.frame(dbcSIM_Poisson$fitted.values) %>%
  round(digits = 0)
Show the code chunk
inter_zonal_flow <- inter_zonal_flow %>%
  cbind(df) %>%
  rename(dbcTRIPS = "dbcSIM_Poisson.fitted.values")

Next, two scatterplots will be created by using geom_point() and other appropriate functions of ggplot2 package.

orc_p <- ggplot(data = inter_zonal_flow,
                aes(x = orcTRIPS,
                    y = TRIPS)) +
  geom_point() +
  geom_smooth(method = lm) +
  coord_cartesian(xlim=c(0,150000),
                  ylim=c(0,150000))

dbc_p <- ggplot(data = inter_zonal_flow,
                aes(x = dbcTRIPS,
                    y = TRIPS)) +
  geom_point() +
  geom_smooth(method = lm) +
  coord_cartesian(xlim=c(0,150000),
                  ylim=c(0,150000))

Now, we will put all the graphs into a single visual for better comparison by using the code chunk below.

ggarrange(orc_p, dbc_p,
          ncol = 2,
          nrow = 1)

Quiz

What observation can you draw from the figure above and what follow-up action will you take?