Load necessary libraries

library(tidyverse)
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library(tidymodels)
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library(h2o)
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## Your next step is to start H2O:
##     > h2o.init()
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## For H2O package documentation, ask for help:
##     > ??h2o
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## After starting H2O, you can use the Web UI at http://localhost:54321
## For more information visit https://docs.h2o.ai
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## Attaching package: 'h2o'
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library(readr)
attrition_raw_tbl <- read_csv("../00_data/WA_Fn-UseC_-HR-Employee-Attrition.csv")
## Rows: 1470 Columns: 35
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr  (9): Attrition, BusinessTravel, Department, EducationField, Gender, Job...
## dbl (26): Age, DailyRate, DistanceFromHome, Education, EmployeeCount, Employ...
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Step 1: Split the data into training and testing sets

set.seed(123) # for reproducibility
split <- initial_split(attrition_raw_tbl, prop = 0.7, strata = "Attrition")
train_data <- training(split)
test_data <- testing(split)

Step 2: Preprocess the data

For simplicity, let’s drop EmployeeNumber and Over18 columns

train_data <- train_data %>%
  select(-c(EmployeeNumber, Over18))
test_data <- test_data %>%
  select(-c(EmployeeNumber, Over18))

Encode categorical variables

train_data <- train_data %>%
  mutate(across(where(is.character), as.factor))
test_data <- test_data %>%
  mutate(across(where(is.character), as.factor))

Step 3: Build a predictive model

h2o.init()
##  Connection successful!
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## R is connected to the H2O cluster: 
##     H2O cluster uptime:         12 days 23 hours 
##     H2O cluster timezone:       America/New_York 
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## Warning in h2o.clusterInfo(): 
## Your H2O cluster version is (4 months and 10 days) old. There may be a newer version available.
## Please download and install the latest version from: https://h2o-release.s3.amazonaws.com/h2o/latest_stable.html

Convert data to h2o frame

train_h2o <- as.h2o(train_data)
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test_h2o <- as.h2o(test_data)
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Specify predictor and response variables

predictors <- setdiff(names(train_data), "Attrition")

Train logistic regression model

model <- h2o.glm(x = predictors, y = "Attrition", training_frame = train_h2o, family = "binomial")
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Step 5: Evaluate the model

Make predictions on test data

predictions <- h2o.predict(model, newdata = test_h2o)
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predicted_probs <- as.vector(predictions$predict)

Compute confusion matrix

predicted_classes <- ifelse(predicted_probs > 0.5, "Yes", "No")
confusion_matrix <- table(test_data$Attrition, predicted_classes)
accuracy <- sum(diag(confusion_matrix)) / sum(confusion_matrix)

print("Confusion Matrix:")
## [1] "Confusion Matrix:"
print(confusion_matrix)
##      predicted_classes
##       Yes
##   No  370
##   Yes  72
print(paste("Accuracy:", accuracy))
## [1] "Accuracy: 0.83710407239819"

Step 6: Predict attrition probability for new data

For new data, use h2o.predict(model, newdata = new_data) with type = “response”