knitr::opts_chunk$set(echo = TRUE, message = FALSE)

Goal is to predict attrition, employees who are likely to leave the company.

Import data

library(tidyverse)

data <- read.csv("C:/Users/tch30/Desktop/PSU_DAT3100/00_data/WA_Fn-UseC_-HR-Employee-Attrition.csv")

Explore data

skimr::skim(data)
Data summary
Name data
Number of rows 1470
Number of columns 35
_______________________
Column type frequency:
character 9
numeric 26
________________________
Group variables None

Variable type: character

skim_variable n_missing complete_rate min max empty n_unique whitespace
Attrition 0 1 2 3 0 2 0
BusinessTravel 0 1 10 17 0 3 0
Department 0 1 5 22 0 3 0
EducationField 0 1 5 16 0 6 0
Gender 0 1 4 6 0 2 0
JobRole 0 1 7 25 0 9 0
MaritalStatus 0 1 6 8 0 3 0
Over18 0 1 1 1 0 1 0
OverTime 0 1 2 3 0 2 0

Variable type: numeric

skim_variable n_missing complete_rate mean sd p0 p25 p50 p75 p100 hist
Age 0 1 36.92 9.14 18 30.00 36.0 43.00 60 ▂▇▇▃▂
DailyRate 0 1 802.49 403.51 102 465.00 802.0 1157.00 1499 ▇▇▇▇▇
DistanceFromHome 0 1 9.19 8.11 1 2.00 7.0 14.00 29 ▇▅▂▂▂
Education 0 1 2.91 1.02 1 2.00 3.0 4.00 5 ▂▃▇▆▁
EmployeeCount 0 1 1.00 0.00 1 1.00 1.0 1.00 1 ▁▁▇▁▁
EmployeeNumber 0 1 1024.87 602.02 1 491.25 1020.5 1555.75 2068 ▇▇▇▇▇
EnvironmentSatisfaction 0 1 2.72 1.09 1 2.00 3.0 4.00 4 ▅▅▁▇▇
HourlyRate 0 1 65.89 20.33 30 48.00 66.0 83.75 100 ▇▇▇▇▇
JobInvolvement 0 1 2.73 0.71 1 2.00 3.0 3.00 4 ▁▃▁▇▁
JobLevel 0 1 2.06 1.11 1 1.00 2.0 3.00 5 ▇▇▃▂▁
JobSatisfaction 0 1 2.73 1.10 1 2.00 3.0 4.00 4 ▅▅▁▇▇
MonthlyIncome 0 1 6502.93 4707.96 1009 2911.00 4919.0 8379.00 19999 ▇▅▂▁▂
MonthlyRate 0 1 14313.10 7117.79 2094 8047.00 14235.5 20461.50 26999 ▇▇▇▇▇
NumCompaniesWorked 0 1 2.69 2.50 0 1.00 2.0 4.00 9 ▇▃▂▂▁
PercentSalaryHike 0 1 15.21 3.66 11 12.00 14.0 18.00 25 ▇▅▃▂▁
PerformanceRating 0 1 3.15 0.36 3 3.00 3.0 3.00 4 ▇▁▁▁▂
RelationshipSatisfaction 0 1 2.71 1.08 1 2.00 3.0 4.00 4 ▅▅▁▇▇
StandardHours 0 1 80.00 0.00 80 80.00 80.0 80.00 80 ▁▁▇▁▁
StockOptionLevel 0 1 0.79 0.85 0 0.00 1.0 1.00 3 ▇▇▁▂▁
TotalWorkingYears 0 1 11.28 7.78 0 6.00 10.0 15.00 40 ▇▇▂▁▁
TrainingTimesLastYear 0 1 2.80 1.29 0 2.00 3.0 3.00 6 ▂▇▇▂▃
WorkLifeBalance 0 1 2.76 0.71 1 2.00 3.0 3.00 4 ▁▃▁▇▂
YearsAtCompany 0 1 7.01 6.13 0 3.00 5.0 9.00 40 ▇▂▁▁▁
YearsInCurrentRole 0 1 4.23 3.62 0 2.00 3.0 7.00 18 ▇▃▂▁▁
YearsSinceLastPromotion 0 1 2.19 3.22 0 0.00 1.0 3.00 15 ▇▁▁▁▁
YearsWithCurrManager 0 1 4.12 3.57 0 2.00 3.0 7.00 17 ▇▂▅▁▁
factors_vec <- data %>% select(Education,EnvironmentSatisfaction, JobInvolvement, PerformanceRating, RelationshipSatisfaction, WorkLifeBalance, JobSatisfaction) %>% names()

data_clean <- data %>%
    
    # Address factors imported as numeric
    mutate(across(all_of(factors_vec), as.factor)) %>%
    
    #Drop zero-variance variables
    select(-c(Over18,EmployeeCount,StandardHours)) %>%
    
    # Recode Attrition
    mutate(Attrition = if_else(Attrition == "Yes", "Left", Attrition))

Explore data

data_clean %>% count(Attrition)
##   Attrition    n
## 1      Left  237
## 2        No 1233
data_clean %>%
    ggplot(aes(Attrition)) +
    geom_bar()

attrition vs. monthly income

data_clean %>%
    ggplot(aes(Attrition, MonthlyIncome)) +
    geom_boxplot()

Correlation Funnel

library(correlationfunnel)
library(dplyr)

data_binarized <- data_clean %>%
    select(-EmployeeNumber) %>%
    binarize()

data_binarized %>% glimpse()
## Rows: 1,470
## Columns: 120
## $ `Age__-Inf_30`                       <dbl> 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, …
## $ Age__30_36                           <dbl> 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, …
## $ Age__36_43                           <dbl> 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ Age__43_Inf                          <dbl> 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, …
## $ Attrition__Left                      <dbl> 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ Attrition__No                        <dbl> 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, …
## $ `BusinessTravel__Non-Travel`         <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ BusinessTravel__Travel_Frequently    <dbl> 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, …
## $ BusinessTravel__Travel_Rarely        <dbl> 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, …
## $ `DailyRate__-Inf_465`                <dbl> 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ DailyRate__465_802                   <dbl> 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, …
## $ DailyRate__802_1157                  <dbl> 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, …
## $ DailyRate__1157_Inf                  <dbl> 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, …
## $ Department__Human_Resources          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ `Department__Research_&_Development` <dbl> 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, …
## $ Department__Sales                    <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ `DistanceFromHome__-Inf_2`           <dbl> 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, …
## $ DistanceFromHome__2_7                <dbl> 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, …
## $ DistanceFromHome__7_14               <dbl> 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ DistanceFromHome__14_Inf             <dbl> 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, …
## $ Education__1                         <dbl> 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, …
## $ Education__2                         <dbl> 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, …
## $ Education__3                         <dbl> 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, …
## $ Education__4                         <dbl> 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, …
## $ Education__5                         <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EducationField__Human_Resources      <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EducationField__Life_Sciences        <dbl> 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, …
## $ EducationField__Marketing            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EducationField__Medical              <dbl> 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, …
## $ EducationField__Other                <dbl> 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EducationField__Technical_Degree     <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EnvironmentSatisfaction__1           <dbl> 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, …
## $ EnvironmentSatisfaction__2           <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EnvironmentSatisfaction__3           <dbl> 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, …
## $ EnvironmentSatisfaction__4           <dbl> 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, …
## $ Gender__Female                       <dbl> 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, …
## $ Gender__Male                         <dbl> 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, …
## $ `HourlyRate__-Inf_48`                <dbl> 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, …
## $ HourlyRate__48_66                    <dbl> 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, …
## $ HourlyRate__66_83.75                 <dbl> 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, …
## $ HourlyRate__83.75_Inf                <dbl> 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, …
## $ JobInvolvement__1                    <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobInvolvement__2                    <dbl> 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ JobInvolvement__3                    <dbl> 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, …
## $ JobInvolvement__4                    <dbl> 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, …
## $ JobLevel__1                          <dbl> 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, …
## $ JobLevel__2                          <dbl> 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, …
## $ JobLevel__3                          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ JobLevel__4                          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobLevel__5                          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole__Healthcare_Representative   <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, …
## $ JobRole__Human_Resources             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole__Laboratory_Technician       <dbl> 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, …
## $ JobRole__Manager                     <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole__Manufacturing_Director      <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ JobRole__Research_Director           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole__Research_Scientist          <dbl> 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole__Sales_Executive             <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole__Sales_Representative        <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobSatisfaction__1                   <dbl> 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, …
## $ JobSatisfaction__2                   <dbl> 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, …
## $ JobSatisfaction__3                   <dbl> 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, …
## $ JobSatisfaction__4                   <dbl> 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, …
## $ MaritalStatus__Divorced              <dbl> 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, …
## $ MaritalStatus__Married               <dbl> 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, …
## $ MaritalStatus__Single                <dbl> 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, …
## $ `MonthlyIncome__-Inf_2911`           <dbl> 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, …
## $ MonthlyIncome__2911_4919             <dbl> 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, …
## $ MonthlyIncome__4919_8379             <dbl> 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, …
## $ MonthlyIncome__8379_Inf              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ `MonthlyRate__-Inf_8047`             <dbl> 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ MonthlyRate__8047_14235.5            <dbl> 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, …
## $ MonthlyRate__14235.5_20461.5         <dbl> 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, …
## $ MonthlyRate__20461.5_Inf             <dbl> 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, …
## $ `NumCompaniesWorked__-Inf_1`         <dbl> 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, …
## $ NumCompaniesWorked__1_2              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ NumCompaniesWorked__2_4              <dbl> 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, …
## $ NumCompaniesWorked__4_Inf            <dbl> 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, …
## $ OverTime__No                         <dbl> 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, …
## $ OverTime__Yes                        <dbl> 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, …
## $ `PercentSalaryHike__-Inf_12`         <dbl> 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, …
## $ PercentSalaryHike__12_14             <dbl> 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, …
## $ PercentSalaryHike__14_18             <dbl> 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ PercentSalaryHike__18_Inf            <dbl> 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, …
## $ PerformanceRating__3                 <dbl> 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, …
## $ PerformanceRating__4                 <dbl> 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, …
## $ RelationshipSatisfaction__1          <dbl> 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, …
## $ RelationshipSatisfaction__2          <dbl> 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, …
## $ RelationshipSatisfaction__3          <dbl> 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, …
## $ RelationshipSatisfaction__4          <dbl> 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, …
## $ StockOptionLevel__0                  <dbl> 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, …
## $ StockOptionLevel__1                  <dbl> 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, …
## $ StockOptionLevel__2                  <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, …
## $ StockOptionLevel__3                  <dbl> 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, …
## $ `TotalWorkingYears__-Inf_6`          <dbl> 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, …
## $ TotalWorkingYears__6_10              <dbl> 1, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, …
## $ TotalWorkingYears__10_15             <dbl> 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, …
## $ TotalWorkingYears__15_Inf            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, …
## $ `TrainingTimesLastYear__-Inf_2`      <dbl> 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, …
## $ TrainingTimesLastYear__2_3           <dbl> 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 0, …
## $ TrainingTimesLastYear__3_Inf         <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, …
## $ WorkLifeBalance__1                   <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ WorkLifeBalance__2                   <dbl> 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, …
## $ WorkLifeBalance__3                   <dbl> 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, …
## $ WorkLifeBalance__4                   <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ `YearsAtCompany__-Inf_3`             <dbl> 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, …
## $ YearsAtCompany__3_5                  <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, …
## $ YearsAtCompany__5_9                  <dbl> 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, …
## $ YearsAtCompany__9_Inf                <dbl> 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ `YearsInCurrentRole__-Inf_2`         <dbl> 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, …
## $ YearsInCurrentRole__2_3              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ YearsInCurrentRole__3_7              <dbl> 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, …
## $ YearsInCurrentRole__7_Inf            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ `YearsSinceLastPromotion__-Inf_1`    <dbl> 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, …
## $ YearsSinceLastPromotion__1_3         <dbl> 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, …
## $ YearsSinceLastPromotion__3_Inf       <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, …
## $ `YearsWithCurrManager__-Inf_2`       <dbl> 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, …
## $ YearsWithCurrManager__2_3            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, …
## $ YearsWithCurrManager__3_7            <dbl> 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, …
## $ YearsWithCurrManager__7_Inf          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, …
#step 2: correlation
data_correlation <- data_binarized %>%
    correlate(Attrition__Left)

data_correlation
## # A tibble: 120 × 3
##    feature           bin       correlation
##    <fct>             <chr>           <dbl>
##  1 Attrition         Left            1    
##  2 Attrition         No             -1    
##  3 OverTime          No             -0.246
##  4 OverTime          Yes             0.246
##  5 JobLevel          1               0.213
##  6 MonthlyIncome     -Inf_2911       0.207
##  7 StockOptionLevel  0               0.195
##  8 YearsAtCompany    -Inf_3          0.183
##  9 MaritalStatus     Single          0.175
## 10 TotalWorkingYears -Inf_6          0.169
## # ℹ 110 more rows
# step 3: plot
data_correlation %>%
    correlationfunnel:: plot_correlation_funnel()
## Warning: ggrepel: 73 unlabeled data points (too many overlaps). Consider
## increasing max.overlaps

Split data

library(tidymodels)
## Warning: package 'tidymodels' was built under R version 4.4.3
## Warning: package 'broom' was built under R version 4.4.3
## Warning: package 'parsnip' was built under R version 4.4.3
## Warning: package 'recipes' was built under R version 4.4.3
## Warning: package 'rsample' was built under R version 4.4.3
## Warning: package 'yardstick' was built under R version 4.4.3
set.seed(1235)
data <- data %>% sample_n(100)

data_split <- initial_split(data, strata = Attrition)
data_train <- training(data_split)
data_test <- testing(data_split)

data_cv <- rsample::vfold_cv(data_train, strata = Attrition)
data_cv
## #  10-fold cross-validation using stratification 
## # A tibble: 10 × 2
##    splits         id    
##    <list>         <chr> 
##  1 <split [66/9]> Fold01
##  2 <split [66/9]> Fold02
##  3 <split [67/8]> Fold03
##  4 <split [68/7]> Fold04
##  5 <split [68/7]> Fold05
##  6 <split [68/7]> Fold06
##  7 <split [68/7]> Fold07
##  8 <split [68/7]> Fold08
##  9 <split [68/7]> Fold09
## 10 <split [68/7]> Fold10

Preprocess data

library(themis)
## Warning: package 'themis' was built under R version 4.4.3
data_rec <- recipes::recipe(Attrition ~ ., data = data_train) %>%
    update_role(EmployeeNumber, new_role = "ID") %>%
    step_rm(Over18) %>%  # Remove column with only one level
    step_dummy(all_nominal_predictors()) %>%
    step_smote(Attrition)

data_rec %>% prep() %>% juice() %>% glimpse()
## Rows: 126
## Columns: 48
## $ Age                               <dbl> 29, 35, 40, 34, 29, 25, 30, 38, 34, …
## $ DailyRate                         <dbl> 1283, 1349, 448, 1333, 461, 675, 135…
## $ DistanceFromHome                  <dbl> 23, 7, 16, 10, 1, 5, 24, 29, 10, 14,…
## $ Education                         <dbl> 3, 2, 3, 4, 3, 2, 1, 3, 4, 2, 4, 4, …
## $ EmployeeCount                     <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, …
## $ EmployeeNumber                    <int> 495, 1601, 1641, 1055, 1753, 369, 11…
## $ EnvironmentSatisfaction           <dbl> 4, 3, 3, 3, 4, 2, 4, 4, 4, 4, 4, 3, …
## $ HourlyRate                        <dbl> 54, 63, 84, 87, 70, 85, 67, 54, 92, …
## $ JobInvolvement                    <dbl> 3, 2, 3, 3, 4, 4, 3, 3, 2, 3, 3, 1, …
## $ JobLevel                          <dbl> 1, 1, 3, 1, 2, 2, 1, 2, 2, 2, 1, 1, …
## $ JobSatisfaction                   <dbl> 4, 4, 4, 3, 3, 1, 3, 4, 3, 1, 3, 4, …
## $ MonthlyIncome                     <dbl> 2201, 2690, 7945, 2220, 6294, 4000, …
## $ MonthlyRate                       <dbl> 18168, 7713, 19948, 18410, 23060, 18…
## $ NumCompaniesWorked                <dbl> 9, 1, 6, 1, 8, 1, 1, 3, 1, 1, 1, 1, …
## $ PercentSalaryHike                 <dbl> 16, 18, 15, 19, 12, 12, 22, 18, 14, …
## $ PerformanceRating                 <dbl> 3, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, …
## $ RelationshipSatisfaction          <dbl> 4, 4, 4, 4, 4, 4, 2, 1, 2, 3, 3, 4, …
## $ StandardHours                     <dbl> 80, 80, 80, 80, 80, 80, 80, 80, 80, …
## $ StockOptionLevel                  <dbl> 0, 1, 0, 1, 0, 2, 1, 1, 1, 1, 0, 1, …
## $ TotalWorkingYears                 <dbl> 6, 1, 18, 1, 10, 6, 1, 9, 8, 5, 8, 4…
## $ TrainingTimesLastYear             <dbl> 4, 5, 2, 2, 5, 2, 2, 3, 3, 2, 3, 5, …
## $ WorkLifeBalance                   <dbl> 3, 2, 2, 3, 4, 3, 3, 1, 2, 3, 3, 3, …
## $ YearsAtCompany                    <dbl> 3, 1, 4, 1, 3, 6, 1, 7, 8, 5, 8, 4, …
## $ YearsInCurrentRole                <dbl> 2, 0, 2, 1, 2, 3, 0, 7, 2, 4, 7, 3, …
## $ YearsSinceLastPromotion           <dbl> 1, 0, 3, 0, 0, 1, 0, 1, 7, 1, 3, 1, …
## $ YearsWithCurrManager              <dbl> 2, 1, 3, 0, 2, 5, 0, 7, 7, 2, 0, 1, …
## $ Attrition                         <fct> No, No, No, No, No, No, No, No, No, …
## $ BusinessTravel_Travel_Frequently  <dbl> 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, …
## $ BusinessTravel_Travel_Rarely      <dbl> 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, …
## $ Department_Research...Development <dbl> 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, …
## $ Department_Sales                  <dbl> 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ EducationField_Life.Sciences      <dbl> 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, …
## $ EducationField_Marketing          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EducationField_Medical            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EducationField_Other              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ EducationField_Technical.Degree   <dbl> 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, …
## $ Gender_Male                       <dbl> 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, …
## $ JobRole_Human.Resources           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole_Laboratory.Technician     <dbl> 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, …
## $ JobRole_Manager                   <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole_Manufacturing.Director    <dbl> 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, …
## $ JobRole_Research.Director         <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ JobRole_Research.Scientist        <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, …
## $ JobRole_Sales.Executive           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, …
## $ JobRole_Sales.Representative      <dbl> 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, …
## $ MaritalStatus_Married             <dbl> 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, …
## $ MaritalStatus_Single              <dbl> 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, …
## $ OverTime_Yes                      <dbl> 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, …

Specify Model

library(usemodels)
## Warning: package 'usemodels' was built under R version 4.4.3
usemodels::use_xgboost(Attrition ~ ., data = data_train)
## xgboost_recipe <- 
##   recipe(formula = Attrition ~ ., data = data_train) %>% 
##   step_zv(all_predictors()) 
## 
## xgboost_spec <- 
##   boost_tree(trees = tune(), min_n = tune(), tree_depth = tune(), learn_rate = tune(), 
##     loss_reduction = tune(), sample_size = tune()) %>% 
##   set_mode("classification") %>% 
##   set_engine("xgboost") 
## 
## xgboost_workflow <- 
##   workflow() %>% 
##   add_recipe(xgboost_recipe) %>% 
##   add_model(xgboost_spec) 
## 
## set.seed(48283)
## xgboost_tune <-
##   tune_grid(xgboost_workflow, resamples = stop("add your rsample object"), grid = stop("add number of candidate points"))
xgboost_rec <- recipe(Attrition ~ ., data = data_train) %>%
    update_role(EmployeeNumber, new_role = "ID") %>%
    step_rm(Over18) %>%  # Remove columns with only one level
    step_dummy(all_nominal_predictors()) %>%
    step_smote(Attrition)
xgboost_spec <-
    boost_tree(trees = tune()) %>%
    set_mode("classification") %>%
    set_engine("xgboost")

xgboost_workflow <-
    workflow() %>%
    add_recipe(xgboost_rec) %>%  # Use the newly defined recipe
    add_model(xgboost_spec)

Tune Hyperparameters

library(doParallel)
## Warning: package 'doParallel' was built under R version 4.4.3
## Warning: package 'foreach' was built under R version 4.4.3
doParallel::registerDoParallel()

set.seed(65743)
xgboost_tune <-
    tune_grid(xgboost_workflow,
              resamples = data_cv,
              grid = 5,
              control = control_grid(save_pred = TRUE))
## Warning: ! tune detected a parallel backend registered with foreach but no backend
##   registered with future.
## ℹ Support for parallel processing with foreach was soft-deprecated in tune
##   1.2.1.
## ℹ See ?parallelism (`?tune::parallelism()`) to learn more.

Model evaluation

Identify optimal values for hyperparameters

collect_metrics(xgboost_tune)
## # A tibble: 15 × 7
##    trees .metric     .estimator  mean     n std_err .config             
##    <int> <chr>       <chr>      <dbl> <int>   <dbl> <chr>               
##  1    12 accuracy    binary     0.732    10  0.0351 Preprocessor1_Model1
##  2    12 brier_class binary     0.205    10  0.0242 Preprocessor1_Model1
##  3    12 roc_auc     binary     0.457    10  0.0893 Preprocessor1_Model1
##  4   507 accuracy    binary     0.746    10  0.0304 Preprocessor1_Model2
##  5   507 brier_class binary     0.193    10  0.0236 Preprocessor1_Model2
##  6   507 roc_auc     binary     0.483    10  0.0944 Preprocessor1_Model2
##  7  1037 accuracy    binary     0.746    10  0.0304 Preprocessor1_Model3
##  8  1037 brier_class binary     0.193    10  0.0236 Preprocessor1_Model3
##  9  1037 roc_auc     binary     0.483    10  0.0944 Preprocessor1_Model3
## 10  1524 accuracy    binary     0.746    10  0.0304 Preprocessor1_Model4
## 11  1524 brier_class binary     0.193    10  0.0236 Preprocessor1_Model4
## 12  1524 roc_auc     binary     0.483    10  0.0944 Preprocessor1_Model4
## 13  1999 accuracy    binary     0.746    10  0.0304 Preprocessor1_Model5
## 14  1999 brier_class binary     0.193    10  0.0236 Preprocessor1_Model5
## 15  1999 roc_auc     binary     0.483    10  0.0944 Preprocessor1_Model5
collect_predictions(xgboost_tune) %>%
    group_by(id) %>%
    roc_curve(Attrition, .pred_Yes, event_level = "second") %>%
    autoplot()

##Fit the model for the last time

library(yardstick)
xgboost_last <- xgboost_workflow %>%
    finalize_workflow(select_best(xgboost_tune)) %>%
    last_fit(data_split)
## Warning in select_best(xgboost_tune): No value of `metric` was given; "roc_auc"
## will be used.
## Warning: package 'xgboost' was built under R version 4.4.3
collect_metrics(xgboost_last)
## # A tibble: 3 × 4
##   .metric     .estimator .estimate .config             
##   <chr>       <chr>          <dbl> <chr>               
## 1 accuracy    binary         0.76  Preprocessor1_Model1
## 2 roc_auc     binary         0.476 Preprocessor1_Model1
## 3 brier_class binary         0.187 Preprocessor1_Model1
collect_predictions(xgboost_last) %>%
    yardstick::conf_mat(Attrition, .pred_class) %>%
    autoplot()

Variable importance

library(vip)
## Warning: package 'vip' was built under R version 4.4.3
xgboost_last %>%
    workflows::extract_fit_engine() %>%
    vip()