11  Logistic Regression with caret

11.1 Install if not Function

install_if_not <- function( list.of.packages ) {
  new.packages <- list.of.packages[!(list.of.packages %in% installed.packages()[,"Package"])]
  if(length(new.packages)) { install.packages(new.packages) } else { print(paste0("the package '", list.of.packages , "' is already installed")) }
}
install_if_not("NHANES")
[1] "the package 'NHANES' is already installed"
install_if_not("RANN")
[1] "the package 'RANN' is already installed"
install_if_not("glmnet")
[1] "the package 'glmnet' is already installed"

11.2 NHANES Dataset

── Attaching core tidyverse packages ──────────────────────── tidyverse 2.0.0 ──
✔ dplyr     1.1.4     ✔ readr     2.1.5
✔ forcats   1.0.0     ✔ stringr   1.5.1
✔ ggplot2   3.5.1     ✔ tibble    3.2.1
✔ lubridate 1.9.3     ✔ tidyr     1.3.1
✔ purrr     1.0.2     
── Conflicts ────────────────────────────────────────── tidyverse_conflicts() ──
✖ dplyr::filter() masks stats::filter()
✖ dplyr::lag()    masks stats::lag()
ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors
library("NHANES")

data <- NHANES %>% select(-DiabetesAge)

dim(data)
[1] 10000    75
glimpse(data)
Rows: 10,000
Columns: 75
$ ID               <int> 51624, 51624, 51624, 51625, 51630, 51638, 51646, 5164…
$ SurveyYr         <fct> 2009_10, 2009_10, 2009_10, 2009_10, 2009_10, 2009_10,…
$ Gender           <fct> male, male, male, male, female, male, male, female, f…
$ Age              <int> 34, 34, 34, 4, 49, 9, 8, 45, 45, 45, 66, 58, 54, 10, …
$ AgeDecade        <fct>  30-39,  30-39,  30-39,  0-9,  40-49,  0-9,  0-9,  40…
$ AgeMonths        <int> 409, 409, 409, 49, 596, 115, 101, 541, 541, 541, 795,…
$ Race1            <fct> White, White, White, Other, White, White, White, Whit…
$ Race3            <fct> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ Education        <fct> High School, High School, High School, NA, Some Colle…
$ MaritalStatus    <fct> Married, Married, Married, NA, LivePartner, NA, NA, M…
$ HHIncome         <fct> 25000-34999, 25000-34999, 25000-34999, 20000-24999, 3…
$ HHIncomeMid      <int> 30000, 30000, 30000, 22500, 40000, 87500, 60000, 8750…
$ Poverty          <dbl> 1.36, 1.36, 1.36, 1.07, 1.91, 1.84, 2.33, 5.00, 5.00,…
$ HomeRooms        <int> 6, 6, 6, 9, 5, 6, 7, 6, 6, 6, 5, 10, 6, 10, 10, 4, 3,…
$ HomeOwn          <fct> Own, Own, Own, Own, Rent, Rent, Own, Own, Own, Own, O…
$ Work             <fct> NotWorking, NotWorking, NotWorking, NA, NotWorking, N…
$ Weight           <dbl> 87.4, 87.4, 87.4, 17.0, 86.7, 29.8, 35.2, 75.7, 75.7,…
$ Length           <dbl> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ HeadCirc         <dbl> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ Height           <dbl> 164.7, 164.7, 164.7, 105.4, 168.4, 133.1, 130.6, 166.…
$ BMI              <dbl> 32.22, 32.22, 32.22, 15.30, 30.57, 16.82, 20.64, 27.2…
$ BMICatUnder20yrs <fct> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ BMI_WHO          <fct> 30.0_plus, 30.0_plus, 30.0_plus, 12.0_18.5, 30.0_plus…
$ Pulse            <int> 70, 70, 70, NA, 86, 82, 72, 62, 62, 62, 60, 62, 76, 8…
$ BPSysAve         <int> 113, 113, 113, NA, 112, 86, 107, 118, 118, 118, 111, …
$ BPDiaAve         <int> 85, 85, 85, NA, 75, 47, 37, 64, 64, 64, 63, 74, 85, 6…
$ BPSys1           <int> 114, 114, 114, NA, 118, 84, 114, 106, 106, 106, 124, …
$ BPDia1           <int> 88, 88, 88, NA, 82, 50, 46, 62, 62, 62, 64, 76, 86, 6…
$ BPSys2           <int> 114, 114, 114, NA, 108, 84, 108, 118, 118, 118, 108, …
$ BPDia2           <int> 88, 88, 88, NA, 74, 50, 36, 68, 68, 68, 62, 72, 88, 6…
$ BPSys3           <int> 112, 112, 112, NA, 116, 88, 106, 118, 118, 118, 114, …
$ BPDia3           <int> 82, 82, 82, NA, 76, 44, 38, 60, 60, 60, 64, 76, 82, 7…
$ Testosterone     <dbl> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ DirectChol       <dbl> 1.29, 1.29, 1.29, NA, 1.16, 1.34, 1.55, 2.12, 2.12, 2…
$ TotChol          <dbl> 3.49, 3.49, 3.49, NA, 6.70, 4.86, 4.09, 5.82, 5.82, 5…
$ UrineVol1        <int> 352, 352, 352, NA, 77, 123, 238, 106, 106, 106, 113, …
$ UrineFlow1       <dbl> NA, NA, NA, NA, 0.094, 1.538, 1.322, 1.116, 1.116, 1.…
$ UrineVol2        <int> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ UrineFlow2       <dbl> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ Diabetes         <fct> No, No, No, No, No, No, No, No, No, No, No, No, No, N…
$ HealthGen        <fct> Good, Good, Good, NA, Good, NA, NA, Vgood, Vgood, Vgo…
$ DaysPhysHlthBad  <int> 0, 0, 0, NA, 0, NA, NA, 0, 0, 0, 10, 0, 4, NA, NA, 0,…
$ DaysMentHlthBad  <int> 15, 15, 15, NA, 10, NA, NA, 3, 3, 3, 0, 0, 0, NA, NA,…
$ LittleInterest   <fct> Most, Most, Most, NA, Several, NA, NA, None, None, No…
$ Depressed        <fct> Several, Several, Several, NA, Several, NA, NA, None,…
$ nPregnancies     <int> NA, NA, NA, NA, 2, NA, NA, 1, 1, 1, NA, NA, NA, NA, N…
$ nBabies          <int> NA, NA, NA, NA, 2, NA, NA, NA, NA, NA, NA, NA, NA, NA…
$ Age1stBaby       <int> NA, NA, NA, NA, 27, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ SleepHrsNight    <int> 4, 4, 4, NA, 8, NA, NA, 8, 8, 8, 7, 5, 4, NA, 5, 7, N…
$ SleepTrouble     <fct> Yes, Yes, Yes, NA, Yes, NA, NA, No, No, No, No, No, Y…
$ PhysActive       <fct> No, No, No, NA, No, NA, NA, Yes, Yes, Yes, Yes, Yes, …
$ PhysActiveDays   <int> NA, NA, NA, NA, NA, NA, NA, 5, 5, 5, 7, 5, 1, NA, 2, …
$ TVHrsDay         <fct> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ CompHrsDay       <fct> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…
$ TVHrsDayChild    <int> NA, NA, NA, 4, NA, 5, 1, NA, NA, NA, NA, NA, NA, 4, N…
$ CompHrsDayChild  <int> NA, NA, NA, 1, NA, 0, 6, NA, NA, NA, NA, NA, NA, 3, N…
$ Alcohol12PlusYr  <fct> Yes, Yes, Yes, NA, Yes, NA, NA, Yes, Yes, Yes, Yes, Y…
$ AlcoholDay       <int> NA, NA, NA, NA, 2, NA, NA, 3, 3, 3, 1, 2, 6, NA, NA, …
$ AlcoholYear      <int> 0, 0, 0, NA, 20, NA, NA, 52, 52, 52, 100, 104, 364, N…
$ SmokeNow         <fct> No, No, No, NA, Yes, NA, NA, NA, NA, NA, No, NA, NA, …
$ Smoke100         <fct> Yes, Yes, Yes, NA, Yes, NA, NA, No, No, No, Yes, No, …
$ Smoke100n        <fct> Smoker, Smoker, Smoker, NA, Smoker, NA, NA, Non-Smoke…
$ SmokeAge         <int> 18, 18, 18, NA, 38, NA, NA, NA, NA, NA, 13, NA, NA, N…
$ Marijuana        <fct> Yes, Yes, Yes, NA, Yes, NA, NA, Yes, Yes, Yes, NA, Ye…
$ AgeFirstMarij    <int> 17, 17, 17, NA, 18, NA, NA, 13, 13, 13, NA, 19, 15, N…
$ RegularMarij     <fct> No, No, No, NA, No, NA, NA, No, No, No, NA, Yes, Yes,…
$ AgeRegMarij      <int> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 20, 15, N…
$ HardDrugs        <fct> Yes, Yes, Yes, NA, Yes, NA, NA, No, No, No, No, Yes, …
$ SexEver          <fct> Yes, Yes, Yes, NA, Yes, NA, NA, Yes, Yes, Yes, Yes, Y…
$ SexAge           <int> 16, 16, 16, NA, 12, NA, NA, 13, 13, 13, 17, 22, 12, N…
$ SexNumPartnLife  <int> 8, 8, 8, NA, 10, NA, NA, 20, 20, 20, 15, 7, 100, NA, …
$ SexNumPartYear   <int> 1, 1, 1, NA, 1, NA, NA, 0, 0, 0, NA, 1, 1, NA, NA, 1,…
$ SameSex          <fct> No, No, No, NA, Yes, NA, NA, Yes, Yes, Yes, No, No, N…
$ SexOrientation   <fct> Heterosexual, Heterosexual, Heterosexual, NA, Heteros…
$ PregnantNow      <fct> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, N…

11.3 Missing data

Amelia::missmap(data)
Warning: Unknown or uninitialised column: `arguments`.
Unknown or uninitialised column: `arguments`.
Warning: Unknown or uninitialised column: `imputations`.

SumNa <- function(col){sum(is.na(col))}

data.sum <- data %>% 
    summarise_all(SumNa) %>%
    tidyr::gather(key='feature', value='SumNa') %>%
    arrange(-SumNa) %>%
    mutate(PctNa = SumNa/nrow(data))

data.sum
# A tibble: 75 × 3
   feature          SumNa PctNa
   <chr>            <int> <dbl>
 1 HeadCirc          9912 0.991
 2 Length            9457 0.946
 3 TVHrsDayChild     9347 0.935
 4 CompHrsDayChild   9347 0.935
 5 BMICatUnder20yrs  8726 0.873
 6 AgeRegMarij       8634 0.863
 7 UrineFlow2        8524 0.852
 8 UrineVol2         8522 0.852
 9 PregnantNow       8304 0.830
10 Age1stBaby        8116 0.812
# ℹ 65 more rows
data.sum2 <- data.sum %>% 
  filter(! (feature %in% c('ID','Diabetes'))) %>%
  filter(PctNa < .45)


data.sum2$feature
 [1] "SexAge"          "SexNumPartnLife" "HardDrugs"       "SexEver"        
 [5] "SameSex"         "AlcoholYear"     "Alcohol12PlusYr" "LittleInterest" 
 [9] "Depressed"       "Education"       "MaritalStatus"   "Smoke100"       
[13] "Smoke100n"       "DaysPhysHlthBad" "DaysMentHlthBad" "HealthGen"      
[17] "SleepHrsNight"   "Work"            "SleepTrouble"    "BPSys1"         
 [ reached getOption("max.print") -- omitted 27 entries ]
data_F <- data %>% 
  select(ID, Diabetes, data.sum2$feature) %>%
  filter(!is.na(Diabetes))

Amelia::missmap(data_F)
Warning: Unknown or uninitialised column: `arguments`.
Unknown or uninitialised column: `arguments`.
Warning: Unknown or uninitialised column: `imputations`.

11.4 Split Data

library('rsample')

set.seed(8675309)

train_test_split <- initial_split(data_F, prop = 3/4) 

TRAIN <- training(train_test_split)
TEST <- testing(train_test_split)

11.5 caret

Loading required package: lattice

Attaching package: 'caret'
The following object is masked from 'package:purrr':

    lift

11.6 dummyVars

dV <- dummyVars(Diabetes ~ .,  TRAIN)

dV
Dummy Variable Object

Formula: Diabetes ~ .
49 variables, 22 factors
Variables and levels will be separated by '.'
A less than full rank encoding is used
dV.TRAIN <- predict(dV, TRAIN)
Warning in model.frame.default(Terms, newdata, na.action = na.action, xlev =
object$lvls): variable 'Diabetes' is not a factor
dV.TRAIN %>%
  glimpse()
 num [1:7393, 1:104] 53639 54356 54171 64860 66251 ...
 - attr(*, "dimnames")=List of 2
  ..$ : chr [1:7393] "1" "2" "3" "4" ...
  ..$ : chr [1:104] "ID" "SexAge" "SexNumPartnLife" "HardDrugs.No" ...

11.7 impute, center, & scale

pP <- preProcess(dV.TRAIN, 
                 method = c('knnImpute', 'center', 'scale'))
pP
Created from 2947 samples and 104 variables

Pre-processing:
  - centered (104)
  - ignored (0)
  - 5 nearest neighbor imputation (104)
  - scaled (104)
pP.dV.TRAIN <- predict(pP, dV.TRAIN)

11.8 train model

trControl <- trainControl(method = 'repeatedcv',
                          number = 10,
                          repeats =  5,
                          search = 'random')

logit.CV <- train(x= pP.dV.TRAIN , y= TRAIN$Diabetes, 
                  method = 'glm',
                  trControl = trControl,
                  family = 'binomial' )
Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred
Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred
Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred
Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred
Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred
logit.CV
Generalized Linear Model 

7393 samples
 104 predictor
   2 classes: 'No', 'Yes' 

No pre-processing
Resampling: Cross-Validated (10 fold, repeated 5 times) 
Summary of sample sizes: 6654, 6653, 6654, 6653, 6654, 6653, ... 
Resampling results:

  Accuracy   Kappa    
  0.9273642  0.2385516

11.9 score test & train data

11.9.1 score test

# score TEST
dV.TEST <- predict(dV, TEST)
Warning in model.frame.default(Terms, newdata, na.action = na.action, xlev =
object$lvls): variable 'Diabetes' is not a factor
pP.dV.TEST <- predict(pP, dV.TEST)

class <- predict(logit.CV, pP.dV.TEST)
probs <- predict(logit.CV, pP.dV.TEST,'prob')

TEST.scored <- cbind(TEST,class,probs) %>% mutate(data = "TEST")

11.9.2 score train

# score TRAIN
class <- predict(logit.CV, pP.dV.TRAIN)
probs <- predict(logit.CV, pP.dV.TRAIN,'prob')

TRAIN.scored <- cbind(TRAIN,class,probs) %>% mutate(data = "TRAIN")


TRAIN_TEST_scored <- rbind(TRAIN.scored, TEST.scored)

11.10 yardstick


Attaching package: 'yardstick'
The following objects are masked from 'package:caret':

    precision, recall, sensitivity, specificity
The following object is masked from 'package:readr':

    spec
TRAIN_TEST_scored_auc <- TRAIN_TEST_scored %>%
  group_by(data) %>%
  roc_auc(truth=Diabetes,Yes, event_level = 'second')


TRAIN_TEST_scored %>%
  left_join(TRAIN_TEST_scored_auc) %>%
  mutate(data = paste(data, " AUC: ", round(.estimate,3))) %>%
  group_by(data) %>%
  roc_curve(truth=Diabetes,Yes, event_level = 'second') %>%
  autoplot()
Joining with `by = join_by(data)`

conf_mat.TRAIN_TEST_scored <- TRAIN_TEST_scored %>%
  group_by(data) %>%
  conf_mat(truth=Diabetes,class)

conf_mat.TRAIN_TEST_scored
# A tibble: 2 × 2
  data  conf_mat  
  <chr> <list>    
1 TEST  <conf_mat>
2 TRAIN <conf_mat>
conf_mat.TRAIN_TEST_scored$conf_mat
[[1]]
          Truth
Prediction   No  Yes
       No  2240  167
       Yes   24   34

[[2]]
          Truth
Prediction   No  Yes
       No  6776  452
       Yes   58  107
metrics.TRAIN_TEST_scored <- map_dfr(conf_mat.TRAIN_TEST_scored$conf_mat,
                                     summary,
                                     .id="data") %>%
                              mutate(data_char = case_when(data == 1 ~ "TEST",
                                                           data == 2 ~ "TRAIN") )

library('ggplot2')

metrics.TRAIN_TEST_scored %>%
  ggplot(aes(x = .metric, y=.estimate, fill= data_char)) +
  geom_bar(stat="identity", position=position_dodge()) +
  coord_flip()