library(readr)
boston <- read_csv("~/Documents/BANA 4080/data/boston.csv")
## Rows: 506 Columns: 16
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## dbl (16): lon, lat, cmedv, crim, zn, indus, chas, nox, rm, age, dis, rad, ta...
##
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.
boston
## # A tibble: 506 × 16
## lon lat cmedv crim zn indus chas nox rm age dis rad
## <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 -71.0 42.3 24 0.00632 18 2.31 0 0.538 6.58 65.2 4.09 1
## 2 -71.0 42.3 21.6 0.0273 0 7.07 0 0.469 6.42 78.9 4.97 2
## 3 -70.9 42.3 34.7 0.0273 0 7.07 0 0.469 7.18 61.1 4.97 2
## 4 -70.9 42.3 33.4 0.0324 0 2.18 0 0.458 7.00 45.8 6.06 3
## 5 -70.9 42.3 36.2 0.0690 0 2.18 0 0.458 7.15 54.2 6.06 3
## 6 -70.9 42.3 28.7 0.0298 0 2.18 0 0.458 6.43 58.7 6.06 3
## 7 -70.9 42.3 22.9 0.0883 12.5 7.87 0 0.524 6.01 66.6 5.56 5
## 8 -70.9 42.3 22.1 0.145 12.5 7.87 0 0.524 6.17 96.1 5.95 5
## 9 -70.9 42.3 16.5 0.211 12.5 7.87 0 0.524 5.63 100 6.08 5
## 10 -70.9 42.3 18.9 0.170 12.5 7.87 0 0.524 6.00 85.9 6.59 5
## # ℹ 496 more rows
## # ℹ 4 more variables: tax <dbl>, ptratio <dbl>, b <dbl>, lstat <dbl>
library(tidymodels)
## ── Attaching packages ────────────────────────────────────── tidymodels 1.2.0 ──
## ✔ broom 1.0.6 ✔ recipes 1.1.0
## ✔ dials 1.3.0 ✔ rsample 1.2.1
## ✔ dplyr 1.1.4 ✔ tibble 3.2.1
## ✔ ggplot2 3.5.1 ✔ tidyr 1.3.1
## ✔ infer 1.0.7 ✔ tune 1.2.1
## ✔ modeldata 1.4.0 ✔ workflows 1.1.4
## ✔ parsnip 1.2.1 ✔ workflowsets 1.1.0
## ✔ purrr 1.0.2 ✔ yardstick 1.3.1
## ── Conflicts ───────────────────────────────────────── tidymodels_conflicts() ──
## ✖ purrr::discard() masks scales::discard()
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag() masks stats::lag()
## ✖ yardstick::spec() masks readr::spec()
## ✖ recipes::step() masks stats::step()
## • Learn how to get started at https://www.tidymodels.org/start/
library(tidyverse)
## ── Attaching core tidyverse packages ──────────────────────── tidyverse 2.0.0 ──
## ✔ forcats 1.0.0 ✔ stringr 1.5.1
## ✔ lubridate 1.9.3
## ── Conflicts ────────────────────────────────────────── tidyverse_conflicts() ──
## ✖ scales::col_factor() masks readr::col_factor()
## ✖ purrr::discard() masks scales::discard()
## ✖ dplyr::filter() masks stats::filter()
## ✖ stringr::fixed() masks recipes::fixed()
## ✖ dplyr::lag() masks stats::lag()
## ✖ yardstick::spec() masks readr::spec()
## ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors
library(vip)
##
## Attaching package: 'vip'
##
## The following object is masked from 'package:utils':
##
## vi
# Part 1
set.seed(123)
split <- initial_split(boston, prop = 0.7, strata = cmedv)
boston_train <- training(split)
boston_test <- testing(split)
# Step 2. create our feature engineering recipe
boston_recipe <- recipe(cmedv ~ ., data = boston_train) %>%
step_YeoJohnson(all_nominal_predictors()) %>%
step_normalize(all_numeric_predictors())
# Step 3. create resampling object
set.seed(123)
kfolds <- vfold_cv(boston_train, v = 5, strata = cmedv)
# Step 4. create our model object
reg_mod <- linear_reg(mixture = tune(), penalty = tune()) %>%
set_engine('glmnet')
# Step 5. create our hyperparameter search grid
reg_grid <- grid_regular(mixture(), penalty(c(-10,5)), levels = 10)
# Step 6. create our workflow object
boston_wf <- workflow() %>%
add_recipe(boston_recipe) %>%
add_model(reg_mod)
# Step 7. perform hyperparamter search
tuning_results <- boston_wf %>%
tune_grid(resamples = kfolds, grid = reg_grid)
## → A | warning: A correlation computation is required, but `estimate` is constant and has 0
## standard deviation, resulting in a divide by 0 error. `NA` will be returned.
## There were issues with some computations A: x1There were issues with some computations A: x2There were issues with some computations A: x3There were issues with some computations A: x4There were issues with some computations A: x5There were issues with some computations A: x5
# Step 8. assess results
tuning_results %>%
collect_metrics() %>%
filter(.metric == "rmse") %>%
arrange(mean)
## # A tibble: 100 × 8
## penalty mixture .metric .estimator mean n std_err .config
## <dbl> <dbl> <chr> <chr> <dbl> <int> <dbl> <chr>
## 1 0.0215 1 rmse standard 4.93 5 0.172 Preprocessor1_M…
## 2 0.0215 0.889 rmse standard 4.93 5 0.172 Preprocessor1_M…
## 3 0.0215 0.778 rmse standard 4.93 5 0.172 Preprocessor1_M…
## 4 0.0215 0.667 rmse standard 4.93 5 0.173 Preprocessor1_M…
## 5 0.0215 0.556 rmse standard 4.93 5 0.173 Preprocessor1_M…
## 6 0.0215 0.444 rmse standard 4.94 5 0.173 Preprocessor1_M…
## 7 0.0215 0.333 rmse standard 4.94 5 0.173 Preprocessor1_M…
## 8 0.0000000001 0.778 rmse standard 4.94 5 0.173 Preprocessor1_M…
## 9 0.00000000464 0.778 rmse standard 4.94 5 0.173 Preprocessor1_M…
## 10 0.000000215 0.778 rmse standard 4.94 5 0.173 Preprocessor1_M…
## # ℹ 90 more rows
autoplot(tuning_results)

# Step 1. finalize our workflow object with the optimal hyperparameter values
best_hyperparameters <- select_best(tuning_results, metric = "rmse")
final_wf <- workflow() %>%
add_recipe(boston_recipe) %>%
add_model(reg_mod) %>%
finalize_workflow(best_hyperparameters)
# Step 2. fit our final workflow object across the full training set data
final_fit <- final_wf %>%
fit(data = boston_train)
# Step 3. plot the top 10 most influential features
final_fit %>%
extract_fit_parsnip() %>%
vip()
