Recently JunYan Jiang published a Chinese Political Elite Database (CPED), which contains demographic and career information of Chinese political leaders from multiple levels. (ref https://www.junyanjiang.com/data.html) It’s a very interesting dataset, here I will use unsupervised machine learning to explore the structure of the dataset and then applied a supervised learning model to predict the highest position of the political leaders with all their background information. All the codes are here https://github.com/luciasalar/government_officials.git
Information in the CPED including: name, gender, ethnicity, birthday, birthplace, education back ground, whether the person join the army, whether the person has been expelled from the Communist Party of China(CPC), current position, whether the person commits a crime, when does the person join CPC, how long does the person work in the government, when and where does the person been relocated, job grade, name of the position and so on.
Before I do any learning, I did a bit of work to process the dataset: 1) convert categorical variables to dummy variables. 2) I extended some variables based on the existing variables on the dataset. I added age by calculating the time difference between now and birthday; added frequency to be relocated (time worked the in government divided by the number of times they were relocated); added number of times worked in the central government; added percentage of central government position to all the positions of each person; added number of times a person been relocated by a national institute or a central government; added number of years they have been working in the government; added number of years they have been in the CPC 3) I also recode the location of where they worked (developing countries and developed countries are assigned into two big groups). However, the location later turns out to be a confusing variable later in the cluster analysis. Maybe I need to identify the location they worked for the longest time and use GDP of the location as weights.
In order to know what variables can predict the highest position of a government official, I do a cluster analysis on the variables. Here I use model based clustering,. The advantage of model based clustering is that it can adapt to Gaussian with non-spherical variance. After a couple of attempts, I find all the extended variables I generated and the job grade produce 9 clusters. Adding other variables, especially the location only confounds the cluster results.
Best BIC values: EEV,9 EEV,8 EEV,7 BIC -40592.79 -44475.21 -48851.12 BIC diff 0.00 -3882.42 -8258.33 $mean [,1] [,2] [,3] [,4] [,5] [,6] [,7] central_freq 4.32237099 8.1333333 3.2921195 6.979184e-01 0.64672483 4.67187223 7.3296655 relocate_freq 12.61755297 19.6000000 18.5603415 1.779856e+01 13.79750420 19.30010818 19.5700083 nat_ins_relo 4.19084397 9.6000000 6.4393863 3.455870e+00 3.99058070 6.99442958 9.5765742 central_relo 0.00000000 1.8333333 0.5695582 6.904707e-04 0.18754764 0.33255111 1.9551820 级别_deputy_director 0.75474248 1.5333333 3.1303437 3.671810e+00 2.48911104 2.07742828 1.5326028 级别_deputy_leader 0.00000000 2.8666667 0.0000000 0.000000e+00 0.00000000 0.06536624 2.0542140 级别_deputy_dept 0.06884181 0.7333333 1.4554218 2.068585e+00 1.28341355 1.31928172 0.9915247 级别_vice_minister 2.49509706 3.2333333 3.2460501 5.323188e-01 0.32912791 4.29367926 3.5884937 级别_less_dept 0.61317397 2.0333333 2.7168478 3.333408e+00 2.39241514 2.71185414 2.4306439 级别_no_rank 0.89761799 1.6333333 1.7226345 1.670180e+00 1.90671226 1.70147894 1.6974206 级别_director 2.09337233 1.5333333 4.3141123 3.500887e+00 3.25762003 2.73690397 2.5425752 级别_national_leader 0.00000000 2.3666667 0.0000000 0.000000e+00 0.00000000 0.00000000 0.0000000 级别_dept 0.33755477 1.2666667 1.9749013 2.942800e+00 2.04231632 1.76069380 1.4218369 级别_minister 1.13393696 2.1333333 0.0000000 0.000000e+00 0.00000000 2.63342184 2.4670000 gov_working_yrs 34.77427264 89.1850000 52.8895299 5.021180e+01 51.41595474 70.20722067 65.0047612 age 69.76954176 80.0189208 62.9543031 6.287416e+01 64.06984368 74.19215959 75.3007443 join_cpc 43.65866150 58.0666667 38.6672922 3.828230e+01 40.33759873 50.62669711 50.1089734 join_cpc_age 25.24244381 22.6220278 23.4355524 2.372276e+01 23.57874446 22.83489307 24.5402508 freq_change_pos_nor 3.02921911 4.9328471 2.9339499 2.935939e+00 4.01097470 3.75754392 3.4275268 central_freq_perce 0.36299367 0.4209026 0.1859861 3.710309e-02 0.04916415 0.25133780 0.3650817 [,8] [,9] central_freq 10.34535743 0.000000000 relocate_freq 19.34634107 6.950475840 nat_ins_relo 11.18794437 0.190331466 central_relo 0.56318475 0.164688275 级别_deputy_director 1.84379429 0.766288984 级别_deputy_leader 0.06257608 0.000000000 级别_deputy_dept 1.53382976 0.113210760 级别_vice_minister 3.28088365 0.609826329 级别_less_dept 1.31481036 0.081245263 级别_no_rank 1.65582924 0.130124281 级别_director 3.31431693 2.268522452 级别_national_leader 0.00000000 0.000000000 级别_dept 1.74969366 0.277415251 级别_minister 2.27820879 0.006609097 gov_working_yrs 47.96463094 17.907235176 age 68.92297628 66.174523443 join_cpc 43.81333803 40.977279532 join_cpc_age 24.99038289 23.577696437 freq_change_pos_nor 2.51541676 3.108479572 central_freq_perce 0.53670229 0.000000000
The above table shows all the variables I used in clustering, freq = frequency, nat_ins_relo = relocated by national institute, central_relo = relocated by central government, gov_working_yrs: number of years working in the government, join_cpc: number of years they join CPC; join_cpc_age : age when they join CPC; central_freq : number of times they worked in the central government; freq_change_pos_nor: frequency of being relocated normalized by the number of years they work in the government; central_freq_perce: number of times working in the central government divided by the number of times being relocated.
It’s hectic work to see what information contained in these groups manually, so I wrote a function to see which cluster has the highest mean score in each variable. We can see that there are a few clusters that are quite important, group 2 contains most national leaders. Let’s call it ‘the leader group; group 3 has most directors let’s call it ‘director group’, group 4 has most deputy directors and deputy department heads, department heads, lower than department head positions, let’s call this group ‘department heads’; group 5 contains officials without rankings, let’s call it ‘no ranking’. group 6 is the ‘ministers’ group, group 8 contains people who works in the central government most number of times. We can also see that officials in the leader group have highest mean age. Group 1 contains least high level government officials, officials in group 9 work in the government shortest period of time. Now we know that unsupervised learning managed to learn some patterns in these variables.
Now let’s do a regression and see if these variables can predict the job grade. We selected the highest job grade of each official as the job grade label. We can see that all the variables we selected are significant in the prediction.
lm(formula = job_grade ~ ., data = reg_fea) Residuals: Min 1Q Median 3Q Max -3.2911 -0.4882 -0.0403 0.4308 5.1570 Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 8.198359 0.159396 51.434 < 2e-16 *** central_freq 0.098955 0.013897 7.121 1.27e-12 *** Freq -0.052931 0.005458 -9.697 < 2e-16 *** nat_ins_relo 0.003095 0.006357 0.487 0.626389 central_relo -0.052582 0.014540 -3.616 0.000303 *** time_diff -0.019530 0.001595 -12.245 < 2e-16 *** age -0.016151 0.005317 -3.038 0.002398 ** join_cpc -0.016090 0.005559 -2.895 0.003817 ** join_cpc_age -0.020595 0.006256 -3.292 0.001004 ** freq_change_pos_nor 0.182062 0.019311 9.428 < 2e-16 *** central_freq_per -2.759989 0.207682 -13.290 < 2e-16 *** --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 Residual standard error: 0.8512 on 3906 degrees of freedom Multiple R-squared: 0.4649, Adjusted R-squared: 0.4635 F-statistic: 339.3 on 10 and 3906 DF, p-value: < 2.2e-16
Ok, the final part is machine learning. Here I produce a very very basic svm model with R. I’ll do a proper ML with Python on a lazy weekend. The basic model turns our really not bad! First, I recode the job grade to binary, with anyone under the minister level as 0, ministers and national leaders are 1. We get a balanced set of data.
0 1 1941 1982
The F1 score is
[1] 0.7790393
confusion matrix
predictions y 0 1 0 477 97 1 156 446