Proposal Draft EHA

Author

Brandon Flores

Bachelors Attainment Between Hispanics and Non Hispanic Whites - An Analysis

Introduction

For this analysis I will observe the possible differences in educational attainment between Hispanics and Non Hispanic Whites. The outcome variable to help measure educational attainment will be whether one received a Bachelors degree or not. It is hypothesized that

h1) those who are Non Hispanic whites will be at greater risk of earning a Bachelors degree as opposed to Hispanics.

The data being used will be the National Longitudinal Study of Youth (NLSY) following the cohort from 1997. For this analysis three waves of data are observed: 2004, 2010, and 2019. In the year of 1997 many of the respondents are still in high school and they are followed throughout high school graduation throughout the rest of their life course. This sample is representative of the national population.

I begin our study by observing the year of 2004 about a few years after the study began to allow time to pass for those respondents to go through high school and be able to earn a Bachelors degree. I present three survival curves for each wave of data to observe those cross sectional relationships between the age when the respondent had earned a Bachelors degree. Next a series of Cox Regression models will be conducted to observe those possible interaction effects that may occur effecting the risk of the age of earning a Bachelors degree between Hispanics and Non Hispanic whites. The different variables that will be observed will be sex, if the father earned a Bachelors degree, if the mother earned a Bachelors degree, the respondents perceived skin tone, and the region of residence of the respondent in 2019.

The Variables

myvars<-c( "ID","HDEGREE04", "HDEGREE2010", "HDEGREE2019","ETHNICITY",
           "SEX", "BIOFTHIGD", "BIOMTHIGD", "BDATEY","VSTRAT", "VPSU",
           "samplingweight","DATEBA", "Rskintone", "Rregion2019")

dat97<-dat97[,myvars]

dat97<- dat97 %>%
  filter(HDEGREE04 >=0, HDEGREE2010>=0, HDEGREE2019>=0, DATEBA >=0, ETHNICITY>=0, SEX>=0, VSTRAT>=0, Rskintone>=0, Rregion2019>=0) #filter missing data codes

Time Constant Variables

Year of Bachelors 2004

Bachelors degree or higher = 1 & all lesser educations are labled 0

dat97$Bachelors_1 <-Recode(dat97$HDEGREE04, recodes = "0:3 = 0; 4:7 = 1; else=NA", as.factor=T)

Year of Bachelors 2010

Bachelors degree or higher = 1 & all lesser educations are labeled 0.

dat97$Bachelors_2 <-Recode(dat97$HDEGREE2010, recodes = "0:3 = 0; 4:7 = 1; else=NA", as.factor=T)

Year of Bachelors 2019

Bachelors degree or higher = 1 & all lesser educations are labeled 0.

dat97$Bachelors_3 <-Recode(dat97$HDEGREE2019, recodes = "0:3 = 0; 4:7 = 1; else=NA", as.factor=T)

Hispanic

Hispanics are coded as 0 & Non Hispanic whites are coded as 1, all other ethnicities are excluded.

dat97$Hispanic<-Recode(dat97$ETHNICITY, recodes = "2 = 0; 4 = 1; else=NA", as.factor=T)

dat97$his1<-as.factor(ifelse(dat97$Hispanic==1, "Hispanic", "Non Hispanic"))

Sex

Women are coded as 0 & Men are coded as 1.

dat97$sex1<-Recode(dat97$SEX, recodes = "1 = 0; 2 = 1; else=NA", as.factor=T)

dat97$sex11<-as.factor(ifelse(dat97$sex1==1, "Women", "Men"))

Bachelors Degree of the Father

Dads Bachelors degree or higher = 1 & all lesser educations are labeled 0.

dat97$DADBA <-Recode(dat97$BIOFTHIGD, recodes = "0:15 = 0; 16:20 = 1; else=NA", as.factor=T)

Bachelors Degree of the Mother

Moms Bachelors degree or higher = 1 & all lesser educations are labeled 0.

dat97$MOMBA <-Recode(dat97$BIOMTHIGD, recodes = "0:15 = 0; 16:20 = 1; else=NA", as.factor=T)

Respondents Skin Tone

Respondents perceived skin tone. 0 to 3 are those perceived with whiter skin tones. Those 4 to 10 are those perceived to have darker skin tones.

dat97$skintone <-Recode(dat97$'Rskintone' , recodes = "0:3 = 0; 4:10 = 1; else=NA", as.factor=T)

Respondents Region of Residence in 2019 living in the Southern US.

Respondents region of residence in 2019. Those 1 (Northeast), 2 (North), and 4 (West)coded into 0 and 3 (South) coded into 1

dat97$south <-Recode(dat97$'Rregion2019' , recodes = "1:2 = 0; 4 = 0; 3 = 1; else=NA", as.factor=T)

Censoring

#dat97<- dat97%>%filter(DATEBA>0)

dat97$BAYR_1<-ifelse(dat97$HDEGREE04==4,
                   (2004-dat97$BDATEY),
                   ifelse(dat97$HDEGREE04>=4,dat97$DATEBA/12,NA)) ## For Censored because they dont have a bachelors degree yet

                  ## For the wave of 2004

Time varying variables

dat97$BAYR_2<-ifelse(dat97$HDEGREE2010==2,
                   (2010-dat97$BDATEY),
                   ifelse(dat97$HDEGREE2010>=4,dat97$DATEBA/12,NA)) ## For Censored because they dont have a bachelors degree yet

                  ## For the wave of 2010
dat97$BAYR_3<-ifelse(dat97$HDEGREE2019==2,
                   (2019-dat97$BDATEY),
                   ifelse(dat97$HDEGREE2019>=4,dat97$DATEBA/12,NA)) ## For Censored because they dont have a bachelors degree yet

                  ## For the wave of 2019

Results

Initial Survival Analysis Observations

dat97<- data.frame(dat97)

fit<-survfit(Surv(time = BAYR_1, event = as.numeric(Bachelors_1) )~his1,
           data = dat97) 

summary(fit)
Call: survfit(formula = Surv(time = BAYR_1, event = as.numeric(Bachelors_1)) ~ 
    his1, data = dat97)

1178 observations deleted due to missingness 
                his1=Hispanic 
 time n.risk n.event survival std.err lower 95% CI upper 95% CI
 21.0    270       2    0.993 0.00522        0.982        1.000
 22.0    268      50    0.807 0.02400        0.762        0.856
 22.5    218       1    0.804 0.02417        0.758        0.853
 23.0    217     117    0.370 0.02939        0.317        0.433
 23.4    100       1    0.367 0.02933        0.313        0.429
 24.0     99      99    0.000     NaN           NA           NA

                his1=Non Hispanic 
 time n.risk n.event survival std.err lower 95% CI upper 95% CI
   21     37       1    0.973  0.0267        0.922        1.000
   22     36       3    0.892  0.0510        0.797        0.998
   23     33      16    0.459  0.0819        0.324        0.652
   24     17      17    0.000     NaN           NA           NA
fit %>%
ggsurvfit()+
  xlim(18, 25)
Warning: Removed 2 row(s) containing missing values (geom_path).

## Wave of 2004

This first survival model observes the year 2004. In this first survival model we observe really no difference between Hispanics and Non Hispanics whites regarding the risk of earning a Bachelors degree. This observes the age interval 18 - 25.

fit1<-survfit(Surv(time = BAYR_2, event = as.numeric(Bachelors_2) )~his1,
           data = dat97) 

summary(fit1)
Call: survfit(formula = Surv(time = BAYR_2, event = as.numeric(Bachelors_2)) ~ 
    his1, data = dat97)

359 observations deleted due to missingness 
                his1=Hispanic 
 time n.risk n.event survival std.err lower 95% CI upper 95% CI
 21.4    918       1  0.99891 0.00109     0.996779       1.0000
 22.0    917       3  0.99564 0.00217     0.991391       0.9999
 22.1    914       1  0.99455 0.00243     0.989804       0.9993
 22.3    913       2  0.99237 0.00287     0.986763       0.9980
 22.4    911      22  0.96841 0.00577     0.957161       0.9798
 22.5    889       6  0.96187 0.00632     0.949565       0.9743
 22.6    883       1  0.96078 0.00641     0.948309       0.9734
 22.7    882       1  0.95969 0.00649     0.947056       0.9725
 23.0    881       8  0.95098 0.00713     0.937116       0.9651
 23.3    873       2  0.94880 0.00727     0.934651       0.9632
 23.4    871      74  0.86819 0.01116     0.846582       0.8904
 23.5    797      11  0.85621 0.01158     0.833810       0.8792
 23.6    786       1  0.85512 0.01162     0.832651       0.8782
 23.7    785       6  0.84858 0.01183     0.825710       0.8721
 24.0    779      27  0.81917 0.01270     0.794650       0.8445
 24.1    752       1  0.81808 0.01273     0.793504       0.8434
 24.2    751       2  0.81590 0.01279     0.791215       0.8414
 24.3    749       8  0.80719 0.01302     0.782069       0.8331
 24.4    741      76  0.72440 0.01475     0.696066       0.7539
 24.5    665       4  0.72004 0.01482     0.691578       0.7497
 24.6    661       1  0.71895 0.01484     0.690456       0.7486
 24.7    660      11  0.70697 0.01502     0.678133       0.7370
 24.8    649       1  0.70588 0.01504     0.677014       0.7360
 25.0    648      28  0.67538 0.01545     0.645761       0.7064
 25.1    620       2  0.67320 0.01548     0.643535       0.7042
 25.3    618      11  0.66122 0.01562     0.631301       0.6926
 25.4    607      90  0.56318 0.01637     0.531993       0.5962
 25.5    517       6  0.55664 0.01640     0.525419       0.5897
 25.6    511       2  0.55447 0.01640     0.523229       0.5876
 25.7    509      13  0.54031 0.01645     0.509009       0.5735
 25.8    496       1  0.53922 0.01645     0.507916       0.5724
 26.0    495      35  0.50109 0.01650     0.469767       0.5345
 26.1    445       1  0.49996 0.01650     0.468641       0.5334
 26.3    444       5  0.49433 0.01651     0.463013       0.5278
 26.4    439      97  0.38511 0.01616     0.354697       0.4181
 26.5    342      18  0.36484 0.01600     0.334784       0.3976
 26.6    324       3  0.36146 0.01597     0.331472       0.3942
 26.7    321       9  0.35133 0.01588     0.321544       0.3839
 26.8    312       3  0.34795 0.01584     0.318238       0.3804
 26.9    309       3  0.34457 0.01581     0.314934       0.3770
 27.0    306      44  0.29502 0.01520     0.266688       0.3264
 27.1    246       1  0.29382 0.01518     0.265520       0.3251
 27.3    245       8  0.28423 0.01506     0.256188       0.3153
 27.4    237      62  0.20987 0.01377     0.184553       0.2387
 27.5    175       4  0.20508 0.01366     0.179977       0.2337
 27.7    171       6  0.19788 0.01349     0.173126       0.2262
 27.8    165       2  0.19548 0.01344     0.170846       0.2237
 27.9    163       2  0.19308 0.01338     0.168567       0.2212
 28.0    161      22  0.16670 0.01268     0.143616       0.1935
 28.1    130       1  0.16542 0.01264     0.142402       0.1922
 28.2    129       2  0.16285 0.01258     0.139976       0.1895
 28.2    127       1  0.16157 0.01254     0.138764       0.1881
 28.3    126       1  0.16029 0.01251     0.137553       0.1868
 28.4    125      27  0.12567 0.01145     0.105122       0.1502
 28.5     98       2  0.12310 0.01135     0.102743       0.1475
 28.6     96       1  0.12182 0.01131     0.101555       0.1461
 28.7     95       2  0.11925 0.01121     0.099181       0.1434
 28.8     93       1  0.11797 0.01117     0.097995       0.1420
 28.8     92       1  0.11669 0.01112     0.096811       0.1407
 29.0     91      18  0.09361 0.01016     0.075664       0.1158
 29.1     59       1  0.09202 0.01011     0.074187       0.1141
 29.3     58       1  0.09044 0.01006     0.072713       0.1125
 29.4     57      14  0.06822 0.00918     0.052411       0.0888
 29.5     43       1  0.06664 0.00910     0.050988       0.0871
 29.6     42       2  0.06346 0.00894     0.048153       0.0836
 29.7     40       2  0.06029 0.00877     0.045335       0.0802
 29.8     38       1  0.05870 0.00868     0.043933       0.0784
 29.8     37       3  0.05394 0.00840     0.039754       0.0732
 30.0     34       7  0.04284 0.00765     0.030189       0.0608
 30.4     18      11  0.01666 0.00575     0.008468       0.0328
 30.5      7       1  0.01428 0.00540     0.006805       0.0300
 30.7      6       2  0.00952 0.00453     0.003747       0.0242
 31.3      4       1  0.00714 0.00397     0.002399       0.0212
 31.4      3       1  0.00476 0.00328     0.001231       0.0184
 33.5      2       1  0.00238 0.00235     0.000343       0.0165
 36.1      1       1  0.00000     NaN           NA           NA

                his1=Non Hispanic 
 time n.risk n.event survival std.err lower 95% CI upper 95% CI
 22.4    208       3   0.9856 0.00827      0.96951       1.0000
 22.5    205       1   0.9808 0.00952      0.96228       0.9996
 22.6    204       1   0.9760 0.01062      0.95537       0.9970
 23.0    203       1   0.9712 0.01161      0.94867       0.9942
 23.1    202       1   0.9663 0.01250      0.94215       0.9912
 23.2    201       1   0.9615 0.01333      0.93576       0.9880
 23.2    200       1   0.9567 0.01411      0.92948       0.9848
 23.4    199       6   0.9279 0.01794      0.89339       0.9637
 23.5    193       3   0.9135 0.01949      0.87604       0.9525
 23.6    190       2   0.9038 0.02044      0.86466       0.9448
 23.7    188       2   0.8942 0.02132      0.85340       0.9370
 23.9    186       1   0.8894 0.02174      0.84781       0.9331
 24.0    185       3   0.8750 0.02293      0.83119       0.9211
 24.3    182       2   0.8654 0.02367      0.82022       0.9130
 24.4    180       8   0.8269 0.02623      0.77708       0.8800
 24.5    172       1   0.8221 0.02652      0.77175       0.8758
 25.0    171       4   0.8029 0.02758      0.75060       0.8588
 25.2    167       1   0.7981 0.02783      0.74535       0.8545
 25.2    166       1   0.7933 0.02808      0.74010       0.8503
 25.3    165       1   0.7885 0.02832      0.73487       0.8460
 25.4    164      16   0.7115 0.03141      0.65256       0.7758
 25.5    148       2   0.7019 0.03172      0.64243       0.7669
 25.8    146       2   0.6923 0.03200      0.63234       0.7580
 25.8    144       2   0.6827 0.03227      0.62228       0.7490
 26.0    142       9   0.6394 0.03329      0.57739       0.7081
 26.3    122       1   0.6342 0.03343      0.57193       0.7032
 26.4    121      20   0.5294 0.03517      0.46472       0.6030
 26.5    101       4   0.5084 0.03531      0.44369       0.5825
 26.6     97       1   0.5032 0.03533      0.43846       0.5774
 26.7     96       1   0.4979 0.03535      0.43323       0.5722
 27.0     95       6   0.4665 0.03537      0.40204       0.5412
 27.4     83      11   0.4046 0.03526      0.34112       0.4800
 27.6     72       1   0.3990 0.03521      0.33565       0.4744
 27.7     71       1   0.3934 0.03516      0.33019       0.4687
 27.8     70       1   0.3878 0.03510      0.32474       0.4631
 28.0     69       7   0.3484 0.03455      0.28690       0.4232
 28.1     56       2   0.3360 0.03442      0.27488       0.4107
 28.2     54       1   0.3298 0.03434      0.26890       0.4044
 28.2     53       1   0.3236 0.03425      0.26293       0.3982
 28.4     52       7   0.2800 0.03336      0.22169       0.3537
 28.5     45       1   0.2738 0.03320      0.21587       0.3472
 29.0     44       5   0.2427 0.03221      0.18708       0.3148
 29.1     32       2   0.2275 0.03193      0.17279       0.2995
 29.4     30       3   0.2047 0.03132      0.15171       0.2763
 29.5     27       2   0.1896 0.03078      0.13791       0.2606
 29.7     25       2   0.1744 0.03013      0.12432       0.2447
 29.8     23       2   0.1592 0.02936      0.11096       0.2286
 30.0     21       3   0.1365 0.02795      0.09138       0.2039
 30.3     11       1   0.1241 0.02803      0.07971       0.1932
 30.4     10       6   0.0496 0.02225      0.02061       0.1195
 30.6      4       1   0.0372 0.01985      0.01309       0.1059
 31.0      3       1   0.0248 0.01667      0.00665       0.0926
 32.4      2       1   0.0124 0.01210      0.00184       0.0839
 32.6      1       1   0.0000     NaN           NA           NA
fit1 %>%
ggsurvfit()+
  xlim(18, 30)
Warning: Removed 15 row(s) containing missing values (geom_path).

## Wave of 2010

The second survival model that is observed is for the year 2010. The age intervals are now between 18 - 30. From this model we can see early really no difference between the age of 18 to about 23 years old. After this age the difference begins to widen with Hispanics being at greater risk of not earning a Bachelors degree compared to Non Hispanics whites. This relationship was not present in the first survival model observing the year 2004.

fit2<-survfit(Surv(time = BAYR_3, event = as.numeric(Bachelors_3) )~his1,
           data = dat97) 

summary(fit2)
Call: survfit(formula = Surv(time = BAYR_3, event = as.numeric(Bachelors_3)) ~ 
    his1, data = dat97)

303 observations deleted due to missingness 
                his1=Hispanic 
 time n.risk n.event survival std.err lower 95% CI upper 95% CI
 21.4    959       1  0.99896 0.00104     0.996917      1.00000
 22.0    958       3  0.99583 0.00208     0.991758      0.99992
 22.1    955       1  0.99479 0.00233     0.990239      0.99935
 22.3    954       2  0.99270 0.00275     0.987328      0.99810
 22.4    952      22  0.96976 0.00553     0.958982      0.98066
 22.5    930       6  0.96350 0.00606     0.951708      0.97545
 22.6    924       1  0.96246 0.00614     0.950506      0.97457
 22.7    923       1  0.96142 0.00622     0.949306      0.97369
 23.0    922       8  0.95308 0.00683     0.939785      0.96655
 23.3    914       2  0.95099 0.00697     0.937425      0.96475
 23.4    912      74  0.87383 0.01072     0.853062      0.89510
 23.5    838      11  0.86236 0.01113     0.840825      0.88444
 23.6    827       1  0.86131 0.01116     0.839715      0.88347
 23.7    826       6  0.85506 0.01137     0.833064      0.87763
 24.0    820      27  0.82690 0.01222     0.803302      0.85120
 24.1    793       1  0.82586 0.01225     0.802204      0.85021
 24.2    792       2  0.82377 0.01230     0.800010      0.84825
 24.3    790       8  0.81543 0.01253     0.791245      0.84036
 24.4    782      76  0.73618 0.01423     0.708813      0.76461
 24.5    706       4  0.73201 0.01430     0.704510      0.76059
 24.6    702       1  0.73097 0.01432     0.703435      0.75958
 24.7    701      11  0.71950 0.01451     0.691621      0.74850
 24.8    690       1  0.71846 0.01452     0.690548      0.74749
 25.0    689      28  0.68926 0.01494     0.660583      0.71918
 25.1    661       2  0.68717 0.01497     0.658448      0.71715
 25.3    659      11  0.67570 0.01512     0.646717      0.70599
 25.4    648      90  0.58186 0.01593     0.551460      0.61393
 25.5    558       6  0.57560 0.01596     0.545153      0.60775
 25.6    552       2  0.57351 0.01597     0.543052      0.60569
 25.7    550      13  0.55996 0.01603     0.529406      0.59227
 25.8    537       1  0.55892 0.01603     0.528358      0.59124
 26.0    536      35  0.52242 0.01613     0.491743      0.55501
 26.1    501       1  0.52138 0.01613     0.490700      0.55397
 26.3    500       5  0.51616 0.01614     0.485483      0.54878
 26.4    495      97  0.41502 0.01591     0.384974      0.44740
 26.5    398      18  0.39625 0.01579     0.366468      0.42844
 26.6    380       3  0.39312 0.01577     0.363388      0.42528
 26.7    377       9  0.38373 0.01570     0.354157      0.41578
 26.8    368       3  0.38060 0.01568     0.351083      0.41261
 26.9    365       3  0.37748 0.01565     0.348010      0.40944
 27.0    362      44  0.33160 0.01520     0.303099      0.36277
 27.1    318       1  0.33055 0.01519     0.302081      0.36171
 27.3    317       8  0.32221 0.01509     0.293950      0.35319
 27.4    309      62  0.25756 0.01412     0.231319      0.28678
 27.5    247       4  0.25339 0.01405     0.227303      0.28247
 27.7    243       6  0.24713 0.01393     0.221286      0.27600
 27.8    237       2  0.24505 0.01389     0.219282      0.27384
 27.9    235       2  0.24296 0.01385     0.217279      0.27168
 28.0    233      22  0.22002 0.01338     0.195304      0.24787
 28.1    211       1  0.21898 0.01335     0.194308      0.24678
 28.2    210       2  0.21689 0.01331     0.192316      0.24461
 28.2    208       1  0.21585 0.01329     0.191321      0.24352
 28.3    207       1  0.21481 0.01326     0.190325      0.24244
 28.4    206      27  0.18665 0.01258     0.163552      0.21302
 28.5    179       2  0.18457 0.01253     0.161577      0.21083
 28.6    177       1  0.18352 0.01250     0.160590      0.20973
 28.7    176       2  0.18144 0.01244     0.158616      0.20755
 28.8    174       1  0.18040 0.01242     0.157630      0.20645
 28.8    173       1  0.17935 0.01239     0.156644      0.20536
 29.0    172      18  0.16058 0.01186     0.138950      0.18559
 29.1    154       1  0.15954 0.01182     0.137970      0.18448
 29.3    153       1  0.15850 0.01179     0.136991      0.18338
 29.4    152      14  0.14390 0.01133     0.123315      0.16792
 29.5    138       1  0.14286 0.01130     0.122341      0.16681
 29.6    137       2  0.14077 0.01123     0.120395      0.16460
 29.7    135       2  0.13869 0.01116     0.118450      0.16238
 29.8    133       1  0.13764 0.01113     0.117478      0.16127
 29.8    132       3  0.13452 0.01102     0.114564      0.15794
 30.0    129       7  0.12722 0.01076     0.107782      0.15015
 30.3    122       1  0.12617 0.01072     0.106815      0.14904
 30.4    121      11  0.11470 0.01029     0.096208      0.13675
 30.5    110       1  0.11366 0.01025     0.095247      0.13563
 30.7    109       2  0.11157 0.01017     0.093326      0.13339
 31.0    107       6  0.10532 0.00991     0.087577      0.12665
 31.3    101       2  0.10323 0.00983     0.085665      0.12440
 31.4     99       7  0.09593 0.00951     0.078993      0.11651
 31.5     92       1  0.09489 0.00946     0.078043      0.11538
 31.6     91       1  0.09385 0.00942     0.077093      0.11424
 31.7     90       1  0.09281 0.00937     0.076144      0.11311
 31.8     89       2  0.09072 0.00927     0.074247      0.11085
 32.0     87       1  0.08968 0.00923     0.073300      0.10971
 32.2     86       1  0.08863 0.00918     0.072354      0.10858
 32.4     85       3  0.08551 0.00903     0.069519      0.10517
 32.5     82       1  0.08446 0.00898     0.068576      0.10403
 32.6     81       1  0.08342 0.00893     0.067633      0.10289
 32.7     80       2  0.08133 0.00883     0.065750      0.10061
 32.9     78       2  0.07925 0.00872     0.063871      0.09833
 33.0     76       5  0.07404 0.00845     0.059188      0.09261
 33.2     71       1  0.07299 0.00840     0.058254      0.09146
 33.3     70       1  0.07195 0.00834     0.057321      0.09031
 33.4     69       6  0.06569 0.00800     0.051744      0.08340
 33.5     63       3  0.06257 0.00782     0.048971      0.07993
 33.6     60       1  0.06152 0.00776     0.048048      0.07877
 33.7     59       1  0.06048 0.00770     0.047127      0.07761
 34.0     58       3  0.05735 0.00751     0.044372      0.07413
 34.3     55       1  0.05631 0.00744     0.043456      0.07296
 34.4     54       6  0.05005 0.00704     0.037991      0.06594
 34.5     48       1  0.04901 0.00697     0.037085      0.06477
 34.6     47       1  0.04797 0.00690     0.036181      0.06359
 34.8     46       3  0.04484 0.00668     0.033480      0.06005
 35.0     43       4  0.04067 0.00638     0.029905      0.05530
 35.4     39       2  0.03858 0.00622     0.028130      0.05292
 36.0     37       1  0.03754 0.00614     0.027246      0.05172
 36.1     36       1  0.03650 0.00606     0.026365      0.05052
 36.2     35       1  0.03545 0.00597     0.025485      0.04932
 36.4     34       3  0.03233 0.00571     0.022864      0.04570
 36.5     31       2  0.03024 0.00553     0.021131      0.04327
 36.7     29       1  0.02920 0.00544     0.020270      0.04206
 36.8     28       1  0.02815 0.00534     0.019411      0.04084
 36.9     27       1  0.02711 0.00524     0.018557      0.03961
 37.0     26       2  0.02503 0.00504     0.016859      0.03715
 37.1     24       1  0.02398 0.00494     0.016016      0.03591
 37.2     23       1  0.02294 0.00483     0.015178      0.03467
 37.4     22       3  0.01981 0.00450     0.012694      0.03092
 37.6     19       1  0.01877 0.00438     0.011877      0.02966
 37.8     18       1  0.01773 0.00426     0.011067      0.02839
 37.9     17       2  0.01564 0.00401     0.009467      0.02584
 38.0     15       2  0.01356 0.00373     0.007900      0.02326
 38.2     13       1  0.01251 0.00359     0.007132      0.02196
 38.4     12       1  0.01147 0.00344     0.006374      0.02064
 38.7     11       1  0.01043 0.00328     0.005629      0.01932
 38.8     10       1  0.00938 0.00311     0.004898      0.01798
 38.9      9       1  0.00834 0.00294     0.004184      0.01663
 39.0      8       2  0.00626 0.00255     0.002818      0.01389
 39.2      6       1  0.00521 0.00233     0.002175      0.01250
 39.4      5       1  0.00417 0.00208     0.001569      0.01109
 39.5      4       1  0.00313 0.00180     0.001011      0.00968
 39.6      3       1  0.00209 0.00147     0.000522      0.00833
 39.7      2       1  0.00104 0.00104     0.000147      0.00740
 40.0      1       1  0.00000     NaN           NA           NA

                his1=Non Hispanic 
 time n.risk n.event survival std.err lower 95% CI upper 95% CI
 22.4    223       3  0.98655 0.00771      0.97154       1.0000
 22.5    220       1  0.98206 0.00889      0.96480       0.9996
 22.6    219       1  0.97758 0.00991      0.95834       0.9972
 23.0    218       1  0.97309 0.01084      0.95209       0.9946
 23.1    217       1  0.96861 0.01168      0.94599       0.9918
 23.2    216       1  0.96413 0.01245      0.94002       0.9888
 23.2    215       1  0.95964 0.01318      0.93416       0.9858
 23.4    214       6  0.93274 0.01677      0.90043       0.9662
 23.5    208       3  0.91928 0.01824      0.88422       0.9557
 23.6    205       2  0.91031 0.01913      0.87357       0.9486
 23.7    203       2  0.90135 0.01997      0.86304       0.9413
 23.9    201       1  0.89686 0.02037      0.85782       0.9377
 24.0    200       3  0.88341 0.02149      0.84227       0.9266
 24.3    197       2  0.87444 0.02219      0.83201       0.9190
 24.4    195       8  0.83857 0.02464      0.79164       0.8883
 24.5    187       1  0.83408 0.02491      0.78666       0.8844
 25.0    186       4  0.81614 0.02594      0.76685       0.8686
 25.2    182       1  0.81166 0.02618      0.76193       0.8646
 25.2    181       1  0.80717 0.02642      0.75702       0.8607
 25.3    180       1  0.80269 0.02665      0.75212       0.8567
 25.4    179      16  0.73094 0.02970      0.67499       0.7915
 25.5    163       2  0.72197 0.03000      0.66550       0.7832
 25.8    161       2  0.71300 0.03029      0.65604       0.7749
 25.8    159       2  0.70404 0.03057      0.64660       0.7666
 26.0    157       9  0.66368 0.03164      0.60448       0.7287
 26.3    148       1  0.65919 0.03174      0.59983       0.7244
 26.4    147      20  0.56951 0.03316      0.50809       0.6383
 26.5    127       4  0.55157 0.03330      0.49001       0.6209
 26.6    123       1  0.54709 0.03333      0.48550       0.6165
 26.7    122       1  0.54260 0.03336      0.48100       0.6121
 27.0    121       6  0.51570 0.03347      0.45410       0.5856
 27.4    115      11  0.46637 0.03341      0.40528       0.5367
 27.6    104       1  0.46188 0.03339      0.40087       0.5322
 27.7    103       1  0.45740 0.03336      0.39647       0.5277
 27.8    102       1  0.45291 0.03333      0.39208       0.5232
 28.0    101       7  0.42152 0.03307      0.36145       0.4916
 28.1     94       2  0.41256 0.03297      0.35275       0.4825
 28.2     92       1  0.40807 0.03291      0.34841       0.4780
 28.2     91       1  0.40359 0.03285      0.34407       0.4734
 28.4     90       7  0.37220 0.03237      0.31387       0.4414
 28.5     83       1  0.36771 0.03229      0.30957       0.4368
 29.0     82       5  0.34529 0.03184      0.28820       0.4137
 29.1     77       2  0.33632 0.03164      0.27969       0.4044
 29.4     75       3  0.32287 0.03131      0.26698       0.3905
 29.5     72       2  0.31390 0.03108      0.25854       0.3811
 29.7     70       2  0.30493 0.03083      0.25012       0.3718
 29.8     68       2  0.29596 0.03057      0.24173       0.3624
 30.0     66       3  0.28251 0.03015      0.22919       0.3482
 30.3     63       1  0.27803 0.03000      0.22503       0.3435
 30.4     62       6  0.25112 0.02904      0.20019       0.3150
 30.6     56       1  0.24664 0.02887      0.19608       0.3102
 31.0     55       1  0.24215 0.02869      0.19198       0.3054
 31.4     54       1  0.23767 0.02850      0.18788       0.3006
 31.5     53       2  0.22870 0.02812      0.17972       0.2910
 31.9     51       1  0.22422 0.02793      0.17565       0.2862
 32.3     50       2  0.21525 0.02752      0.16753       0.2766
 32.4     48       4  0.19731 0.02665      0.15142       0.2571
 32.5     44       1  0.19283 0.02642      0.14741       0.2522
 32.6     43       1  0.18834 0.02618      0.14342       0.2473
 32.8     42       1  0.18386 0.02594      0.13944       0.2424
 33.0     41       2  0.17489 0.02544      0.13151       0.2326
 33.4     39       1  0.17040 0.02518      0.12756       0.2276
 33.5     38       1  0.16592 0.02491      0.12362       0.2227
 33.7     37       1  0.16143 0.02464      0.11970       0.2177
 33.9     36       1  0.15695 0.02436      0.11579       0.2128
 34.0     35       1  0.15247 0.02407      0.11189       0.2078
 34.4     34       4  0.13453 0.02285      0.09644       0.1877
 34.5     30       1  0.13004 0.02252      0.09261       0.1826
 35.0     29       1  0.12556 0.02219      0.08880       0.1775
 35.4     28       2  0.11659 0.02149      0.08124       0.1673
 35.7     26       1  0.11211 0.02113      0.07749       0.1622
 35.8     25       1  0.10762 0.02075      0.07375       0.1571
 36.0     24       3  0.09417 0.01956      0.06268       0.1415
 36.3     21       1  0.08969 0.01913      0.05904       0.1362
 36.4     20       2  0.08072 0.01824      0.05183       0.1257
 36.8     18       1  0.07623 0.01777      0.04828       0.1204
 37.4     17       2  0.06726 0.01677      0.04126       0.1097
 37.7     15       1  0.06278 0.01624      0.03781       0.1042
 38.0     14       3  0.04933 0.01450      0.02772       0.0878
 38.4     11       2  0.04036 0.01318      0.02128       0.0765
 38.6      9       1  0.03587 0.01245      0.01817       0.0708
 39.0      8       1  0.03139 0.01168      0.01514       0.0651
 39.4      7       2  0.02242 0.00991      0.00943       0.0533
 39.5      5       1  0.01794 0.00889      0.00679       0.0474
 39.6      4       1  0.01345 0.00771      0.00437       0.0414
 39.7      3       1  0.00897 0.00631      0.00226       0.0356
 40.0      2       2  0.00000     NaN           NA           NA
fit2 %>%
ggsurvfit()+
  xlim(18, 45)
Warning: Removed 2 row(s) containing missing values (geom_path).

## Wave of 2019

The third survival model that is observed is for the age intervals between 18 - 45. This continued statistically significant difference in the risk of earning a Bachelors degree; with Hispanics being at greater risk of not earning a Bachelors compared to Non Hispanic whites. Although from this model it seems to come close to a state of no statistical difference at the age of 40.

Risk Set

dat97<-dat97%>% filter(is.na(Bachelors_1)==F &
                  is.na(Bachelors_2)==F &
                  is.na(Bachelors_3)==F & 
                  is.na(BAYR_1)==F &
                  is.na(BAYR_2)==F &
                  is.na(BAYR_3)==F &
                    Bachelors_1!=1)

Pivot

e.long1 <- dat97 %>%
  #rename
  rename(wt = samplingweight,strata= VSTRAT, psu = VPSU)%>%
  select(ID, psu,wt,strata,his1,sex11,DADBA,MOMBA,DATEBA,south,skintone,   #time constant
        BAYR_1, BAYR_2, BAYR_3, #t-varying variables
         Bachelors_1, Bachelors_2, Bachelors_3)%>%
   pivot_longer(cols = c(-ID,-psu, -wt, -strata, -his1, -sex11, -MOMBA, -DADBA, -DATEBA, -south, -skintone), #error here
               names_to  = c(".value", "wave"), #make wave variable and put t-v vars into columns
               names_sep = "_")%>% #all t-v variables have _ between name and time, like age_1, age_2
  group_by(ID)%>%
   mutate(age_enter = DATEBA, 
         age_exit = lead(DATEBA, 1, order_by=ID))%>%
  mutate(nexBA = dplyr::lead(Bachelors,n=1, order_by = ID))%>%
  mutate(BAtran = ifelse(nexBA == 1 & Bachelors == 0, 1, 0))%>%
  filter(is.na(age_exit)==F)%>%
  ungroup()%>%
  
    filter(complete.cases(age_enter, age_exit, BAtran,
                        his1, MOMBA, DADBA, sex11, psu, south, skintone))
options(survey.lonely.psu = "adjust")

des2<-svydesign(ids = ~psu, #error here
                strata = ~strata,
                weights =~wt, 
                data=e.long1,
                nest=T)

Cox Regression Hispanics and Skin Tone

f1 <- survfit(Surv(time = age_enter, event = BAtran)~his1+skintone, data=e.long1)

f1%>%
  ggsurvfit()

#Fit the model
fitskintone<-svycoxph(Surv(time = age_enter, event = BAtran)~his1*skintone, design=des2)
summary(fitskintone)
Stratified 1 - level Cluster Sampling design (with replacement)
With (168) clusters.
svydesign(ids = ~psu, strata = ~strata, weights = ~wt, data = e.long1, 
    nest = T)
Call:
svycoxph(formula = Surv(time = age_enter, event = BAtran) ~ his1 * 
    skintone, design = des2)

  n= 1758, number of events= 638 

                               coef exp(coef) se(coef) robust se      z
his1Non Hispanic           -0.29195   0.74681  0.13857   0.15224 -1.918
skintone1                   0.12395   1.13196  0.29353   0.38821  0.319
his1Non Hispanic:skintone1  0.04464   1.04565  0.44616   0.50153  0.089
                           Pr(>|z|)  
his1Non Hispanic             0.0551 .
skintone1                    0.7495  
his1Non Hispanic:skintone1   0.9291  
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

                           exp(coef) exp(-coef) lower .95 upper .95
his1Non Hispanic              0.7468     1.3390    0.5541     1.006
skintone1                     1.1320     0.8834    0.5289     2.423
his1Non Hispanic:skintone1    1.0457     0.9563    0.3913     2.794

Concordance= 0.516  (se = 0.006 )
Likelihood ratio test= NA  on 3 df,   p=NA
Wald test            = 3.96  on 3 df,   p=0.3
Score (logrank) test = NA  on 3 df,   p=NA

  (Note: the likelihood ratio and score tests assume independence of
     observations within a cluster, the Wald and robust score tests do not).

This first Cox Regression is used to measure the risk of earning a Bachelors degree between Hispanics and Non Hispanic whites in associaiton with skin tone. When observing the model; the variable Hispanic was found with a marginal effect with those who are Hispanic about 26% less likely to earn a Bachelors degree compared to Non Hispanic whites. When placed together with the interaction term (*) the marginal effect is lost.

Cox Regression Hispanics and region of residency in the South

f2 <- survfit(Surv(time = age_enter, event = BAtran)~his1+south, data=e.long1)

f2%>%
  ggsurvfit()

#Fit the model
fitSouth<-svycoxph(Surv(time = age_enter, event = BAtran)~his1*south, design=des2)
summary(fitSouth)
Stratified 1 - level Cluster Sampling design (with replacement)
With (168) clusters.
svydesign(ids = ~psu, strata = ~strata, weights = ~wt, data = e.long1, 
    nest = T)
Call:
svycoxph(formula = Surv(time = age_enter, event = BAtran) ~ his1 * 
    south, design = des2)

  n= 1758, number of events= 638 

                            coef exp(coef) se(coef) robust se      z Pr(>|z|)
his1Non Hispanic        -0.28344   0.75319  0.16428   0.19090 -1.485    0.138
south1                  -0.09592   0.90854  0.08482   0.10466 -0.916    0.359
his1Non Hispanic:south1  0.05319   1.05463  0.26314   0.23421  0.227    0.820

                        exp(coef) exp(-coef) lower .95 upper .95
his1Non Hispanic           0.7532     1.3277    0.5181     1.095
south1                     0.9085     1.1007    0.7400     1.115
his1Non Hispanic:south1    1.0546     0.9482    0.6664     1.669

Concordance= 0.524  (se = 0.011 )
Likelihood ratio test= NA  on 3 df,   p=NA
Wald test            = 4.84  on 3 df,   p=0.2
Score (logrank) test = NA  on 3 df,   p=NA

  (Note: the likelihood ratio and score tests assume independence of
     observations within a cluster, the Wald and robust score tests do not).

This second Cox Regression is used to measure the risk of earning a Bachelors degree between Hispanics and Non Hispanic whites in association with living in the Southern region of the US. When observing the model; non of the variables in the model are statistically significant.

Cox Regression Hispanics only

f3 <- survfit(Surv(time = age_enter, event = BAtran)~his1, data=e.long1)

f3%>%
  ggsurvfit()

#Fit the model
fithis<-svycoxph(Surv(time = age_enter, event = BAtran)~his1, design=des2)
summary(fithis)
Stratified 1 - level Cluster Sampling design (with replacement)
With (168) clusters.
svydesign(ids = ~psu, strata = ~strata, weights = ~wt, data = e.long1, 
    nest = T)
Call:
svycoxph(formula = Surv(time = age_enter, event = BAtran) ~ his1, 
    design = des2)

  n= 1758, number of events= 638 

                    coef exp(coef) se(coef) robust se      z Pr(>|z|)  
his1Non Hispanic -0.2695    0.7637   0.1282    0.1390 -1.939   0.0526 .
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

                 exp(coef) exp(-coef) lower .95 upper .95
his1Non Hispanic    0.7637      1.309    0.5816     1.003

Concordance= 0.515  (se = 0.006 )
Likelihood ratio test= NA  on 1 df,   p=NA
Wald test            = 3.76  on 1 df,   p=0.05
Score (logrank) test = NA  on 1 df,   p=NA

  (Note: the likelihood ratio and score tests assume independence of
     observations within a cluster, the Wald and robust score tests do not).

The third Cox Regression is used to measure the risk of earning a Bachelors degree between Hispanics and Non Hispanic whites only. When observing the model; Hispanics are found to have a marginal effect with Hispanics about 24% less likely to earn a Bachelors degree compared to their Non Hispanic white counterparts.

Cox Regression Hispanics and Bachelors Degree of the Father

f4 <- survfit(Surv(time = age_enter, event = BAtran)~his1+DADBA, data=e.long1)

f4%>%
  ggsurvfit()

#Fit the model
fitDADBA<-svycoxph(Surv(time = age_enter, event = BAtran)~his1*DADBA, design=des2)
summary(fitDADBA)
Stratified 1 - level Cluster Sampling design (with replacement)
With (168) clusters.
svydesign(ids = ~psu, strata = ~strata, weights = ~wt, data = e.long1, 
    nest = T)
Call:
svycoxph(formula = Surv(time = age_enter, event = BAtran) ~ his1 * 
    DADBA, design = des2)

  n= 1758, number of events= 638 

                            coef exp(coef) se(coef) robust se      z Pr(>|z|)
his1Non Hispanic        -0.14940   0.86123  0.15119   0.20259 -0.737    0.461
DADBA1                   0.38760   1.47344  0.08091   0.07996  4.848 1.25e-06
his1Non Hispanic:DADBA1 -0.25017   0.77867  0.29109   0.33251 -0.752    0.452
                           
his1Non Hispanic           
DADBA1                  ***
his1Non Hispanic:DADBA1    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

                        exp(coef) exp(-coef) lower .95 upper .95
his1Non Hispanic           0.8612     1.1611    0.5790     1.281
DADBA1                     1.4734     0.6787    1.2597     1.723
his1Non Hispanic:DADBA1    0.7787     1.2842    0.4058     1.494

Concordance= 0.546  (se = 0.012 )
Likelihood ratio test= NA  on 3 df,   p=NA
Wald test            = 25.43  on 3 df,   p=1e-05
Score (logrank) test = NA  on 3 df,   p=NA

  (Note: the likelihood ratio and score tests assume independence of
     observations within a cluster, the Wald and robust score tests do not).

The fourth Cox Regression is used to measure the risk of earning a Bachelors degree between Hispanics and Non Hispanic whites in association with Fathers who have earned a Bachelors degree. When observing the model; Fathers who have earned a Bachelors are statistically significant at the p<001 level (***) with those respondents who have a Father that has a Bachelors degree are about 47% more likely to earn a Bachelors degree themselves as opposed to those respondents whos Father did not earn a Bachelors degree. The variable Hispanic is not statistically significant in this model. When these two variables are placed with a interaction term that significance is lost.

Cox Regression Hispanics and Bachelors Degree of the Mother

f5 <- survfit(Surv(time = age_enter, event = BAtran)~his1+MOMBA, data=e.long1)

f5%>%
  ggsurvfit()

#Fit the model
fitMOMBA<-svycoxph(Surv(time = age_enter, event = BAtran)~his1*MOMBA, design=des2)
summary(fitMOMBA)
Stratified 1 - level Cluster Sampling design (with replacement)
With (168) clusters.
svydesign(ids = ~psu, strata = ~strata, weights = ~wt, data = e.long1, 
    nest = T)
Call:
svycoxph(formula = Surv(time = age_enter, event = BAtran) ~ his1 * 
    MOMBA, design = des2)

  n= 1758, number of events= 638 

                            coef exp(coef) se(coef) robust se      z Pr(>|z|)
his1Non Hispanic        -0.11864   0.88813  0.15090   0.16979 -0.699 0.484708
MOMBA1                   0.35608   1.42772  0.07984   0.09342  3.811 0.000138
his1Non Hispanic:MOMBA1 -0.39651   0.67266  0.29044   0.32562 -1.218 0.223336
                           
his1Non Hispanic           
MOMBA1                  ***
his1Non Hispanic:MOMBA1    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

                        exp(coef) exp(-coef) lower .95 upper .95
his1Non Hispanic           0.8881     1.1260    0.6367     1.239
MOMBA1                     1.4277     0.7004    1.1888     1.715
his1Non Hispanic:MOMBA1    0.6727     1.4866    0.3553     1.273

Concordance= 0.552  (se = 0.012 )
Likelihood ratio test= NA  on 3 df,   p=NA
Wald test            = 21.44  on 3 df,   p=9e-05
Score (logrank) test = NA  on 3 df,   p=NA

  (Note: the likelihood ratio and score tests assume independence of
     observations within a cluster, the Wald and robust score tests do not).

The fifth Cox Regression is used to measure the risk of earning a Bachelors degree between Hispanics and Non Hispanic whites in association with Mothers who have earned a Bachelors degree. When observing the model; Mothers who have earned a Bachelors are statistically significant at the p<001 level (***) with those respondents who have a Mother that has a Bachelors degree are about 42% more likely to earn a Bachelors degree themselves as opposed to those respondents whose Mother did not earn a Bachelors degree. The variable Hispanic is not statistically significant in this model. When these two variables are placed with a interaction term that significance is lost.

Cox Regression Hispanics and sex

f6 <- survfit(Surv(time = age_enter, event = BAtran)~his1+sex11, data=e.long1)

f6%>%
  ggsurvfit()

#Fit the model
fitsex<-svycoxph(Surv(time = age_enter, event = BAtran)~his1*sex11, design=des2)
summary(fitsex)
Stratified 1 - level Cluster Sampling design (with replacement)
With (168) clusters.
svydesign(ids = ~psu, strata = ~strata, weights = ~wt, data = e.long1, 
    nest = T)
Call:
svycoxph(formula = Surv(time = age_enter, event = BAtran) ~ his1 * 
    sex11, design = des2)

  n= 1758, number of events= 638 

                                coef exp(coef) se(coef) robust se      z
his1Non Hispanic            -0.31902   0.72686  0.17542   0.20024 -1.593
sex11Women                  -0.03268   0.96785  0.07875   0.08456 -0.386
his1Non Hispanic:sex11Women  0.10524   1.11098  0.25660   0.28409  0.370
                            Pr(>|z|)
his1Non Hispanic               0.111
sex11Women                     0.699
his1Non Hispanic:sex11Women    0.711

                            exp(coef) exp(-coef) lower .95 upper .95
his1Non Hispanic               0.7269     1.3758    0.4909     1.076
sex11Women                     0.9679     1.0332    0.8200     1.142
his1Non Hispanic:sex11Women    1.1110     0.9001    0.6366     1.939

Concordance= 0.506  (se = 0.012 )
Likelihood ratio test= NA  on 3 df,   p=NA
Wald test            = 4.09  on 3 df,   p=0.3
Score (logrank) test = NA  on 3 df,   p=NA

  (Note: the likelihood ratio and score tests assume independence of
     observations within a cluster, the Wald and robust score tests do not).

The final Cox Regression model is used to measure the risk of earning a Bachelors degree between Hispanics and Non Hispanic whites in association with the respondents sex. When observing the model; none of the variables in the model are statistically significant.

Grambsch and Therneau (1994) Test

Overall, none of the models are statistically significant meaning that all variables are implying proportionality of effect. Being that none of the variables are correlated with the timing of the transition. This furthers the reliability of the observed Cox Regression Models.

skintone

fit.test1<-cox.zph(fitskintone)
fit.test1
                 chisq df    p
his1          5.24e-04  1 0.98
skintone      1.00e-03  1 0.97
his1:skintone 5.83e-05  1 0.99
GLOBAL        1.48e-03  3 1.00
plot(fit.test1, df=2)

South Region Residency

fit.test2<-cox.zph(fitSouth)
fit.test2
              chisq df    p
his1       5.68e-04  1 0.98
south      4.92e-06  1 1.00
his1:south 4.03e-05  1 0.99
GLOBAL     6.11e-04  3 1.00
plot(fit.test2, df=2)

Hispanics

fit.test3<-cox.zph(fithis)
fit.test3
          chisq df    p
his1   0.000536  1 0.98
GLOBAL 0.000536  1 0.98
plot(fit.test3, df=2)

Bachelors Degree for Fathers

fit.test4<-cox.zph(fitDADBA)
fit.test4
              chisq df    p
his1       7.54e-04  1 0.98
DADBA      7.53e-05  1 0.99
his1:DADBA 1.84e-05  1 1.00
GLOBAL     8.16e-04  3 1.00
plot(fit.test4, df=2)

Bachelors Degree for Mothers

fit.test5<-cox.zph(fitMOMBA)
fit.test5
              chisq df    p
his1       7.40e-04  1 0.98
MOMBA      9.06e-06  1 1.00
his1:MOMBA 1.56e-04  1 0.99
GLOBAL     8.64e-04  3 1.00
plot(fit.test5, df=2)

sex

fit.test6<-cox.zph(fitsex)
fit.test6
              chisq df    p
his1       5.62e-04  1 0.98
sex11      2.78e-04  1 0.99
his1:sex11 1.18e-05  1 1.00
GLOBAL     9.25e-04  3 1.00
plot(fit.test6, df=2)

Conclusions

From the findings overall the hypothesis (h1) was not supported by analysis of the various Cox Regression Models. Only at a couple of time was there only but a marginal effect had between Hispanics and Non Hispanic whites concerning the risk of earning a Bachelors degree. With model one observing skin tone it is interesting that the skin tone variable was not able to take away the marginal effect had on the Hispanic variable. Meaning that evening accounting for the respondents skin color they are still slightly facing a educational disparity in terms of earning a Bachelors degree over the life course in the US. This is controlled for with the interaction term. This marginal effect with Hispanics is found again with only observing Hispanics in the model.

The two variables with the largest statistical significance would be the variables of observing the Mother’s and the Father’s educational attainment of whether or not they earned a Bachelors degree. Both variables showed over 40% of their children more likely to earn a Bachelors degree. When these variables are placed into interaction effects with Hispanics the statistical significance is lost for both variables in both models respectively.

The Grambsch and Therneau (1994) Tests conducted for each model further solidifies the reliability of the results that were generated.

When observing Hispanics between the years of 2004 and 2019 although there may be found some slight differences in educational attainment. That difference is lost especially as the cohort ages. The importance of parental educational attainment is found throughout theses models for both the Mother and the Father.

Future research is to be done for the different instances of entering into college, quality of education, and occupation attainment after graduation.