PCA in tidymodels

From a model building perspective, PCA allows you to create models with fewer features, but still capture most of the information in the original data. However, as you've seen, a disadvantage of PCA is the difficulty of interpreting the model. In this exercise, you will be focusing on building a linear regression model using a subset of the house sales data. The target variable is price.

A model built directly from the data without extracting principal components has a RMSE of $236,461.4. You will apply PCA with tidymodels and compare the new RMSE. Remember, lower RMSEs are better.

The tidyverse and tidymodels packages have been loaded for you.

แบบฝึกหัดนี้เป็นส่วนหนึ่งของหลักสูตร

Dimensionality Reduction in R

ดูคอร์ส

คำแนะนำการฝึกหัด

Build a PCA recipe using train to extract five principal components.
Fit a workflow with a default linear_reg() model spec.
Create a test prediction data frame using test that contains the actual and predicted values.
Calculate the RMSE for the PCA-reduced linear regression model.

แบบฝึกหัดเชิงโต้ตอบแบบลงมือทำ

ลองทำแบบฝึกหัดนี้โดยเติมโค้ดตัวอย่างนี้ให้สมบูรณ์

# Build a PCA recipe
pca_recipe <- ___(___ ~ ___ , data = ___) %>% 
  ___(___()) %>% 
  ___(___(), num_comp = ___) 

# Fit a workflow with a default linear_reg() model spec
house_sales_fit <- ___(preprocessor = ___, spec = ___()) %>% 
  ___(___)

# Create prediction df for the test set
house_sales_pred_df <- ___(___, test) %>% 
  ___(test %>% select(___))

# Calculate the RMSE
___(house_sales_pred_df, ___, .pred)

แก้ไขและรันโค้ด