Click here for the data. Goal: Predict future price of IKEA furniture

Import data

ikea <- readr::read_csv('https://raw.githubusercontent.com/rfordatascience/tidytuesday/master/data/2020/2020-11-03/ikea.csv')
## New names:
## Rows: 3694 Columns: 14
## ── Column specification
## ──────────────────────────────────────────────────────── Delimiter: "," chr
## (7): name, category, old_price, link, other_colors, short_description, d... dbl
## (6): ...1, item_id, price, depth, height, width lgl (1): sellable_online
## 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.
## • `` -> `...1`
skimr::skim(ikea)
Data summary
Name ikea
Number of rows 3694
Number of columns 14
_______________________
Column type frequency:
character 7
logical 1
numeric 6
________________________
Group variables None

Variable type: character

skim_variable n_missing complete_rate min max empty n_unique whitespace
name 0 1 3 27 0 607 0
category 0 1 4 36 0 17 0
old_price 0 1 4 13 0 365 0
link 0 1 52 163 0 2962 0
other_colors 0 1 2 3 0 2 0
short_description 0 1 3 63 0 1706 0
designer 0 1 3 1261 0 381 0

Variable type: logical

skim_variable n_missing complete_rate mean count
sellable_online 0 1 0.99 TRU: 3666, FAL: 28

Variable type: numeric

skim_variable n_missing complete_rate mean sd p0 p25 p50 p75 p100 hist
…1 0 1.00 1846.50 1066.51 0 923.25 1846.5 2769.75 3693 ▇▇▇▇▇
item_id 0 1.00 48632396.79 28887094.10 58487 20390574.00 49288078.0 70403572.75 99932615 ▇▇▇▇▇
price 0 1.00 1078.21 1374.65 3 180.90 544.7 1429.50 9585 ▇▁▁▁▁
depth 1463 0.60 54.38 29.96 1 38.00 47.0 60.00 257 ▇▃▁▁▁
height 988 0.73 101.68 61.10 1 67.00 83.0 124.00 700 ▇▂▁▁▁
width 589 0.84 104.47 71.13 1 60.00 80.0 140.00 420 ▇▅▂▁▁
data <- ikea %>%
  
  # Handle missing values
  filter(!is.na(height), !is.na(width), !is.na(depth)) %>%
  
  # Convert all character variables to factors for machine learning compatibility
  mutate(across(where(is.character), as.factor)) %>% 
  
      mutate(across(is.logical, as.factor)) %>%


  # Handle multiple designers by splitting them into separate rows
  separate_rows(designer, sep = "/") %>%

  # Remove unnecessary columns
  select(-...1, -link, -old_price, -designer, -name) %>%
  
  # Log transform price to address skewness
  mutate(price = log(price))
## Warning: There was 1 warning in `mutate()`.
## ℹ In argument: `across(is.logical, as.factor)`.
## Caused by warning:
## ! Use of bare predicate functions was deprecated in tidyselect 1.1.0.
## ℹ Please use wrap predicates in `where()` instead.
##   # Was:
##   data %>% select(is.logical)
## 
##   # Now:
##   data %>% select(where(is.logical))

Explore Data - Identifying good predictors

# Step 1: Prepare data by binarising data
binarized_table <- data %>%
    select(-item_id, -short_description) %>%
    binarize()

binarized_table %>% glimpse()
## Rows: 2,714
## Columns: 35
## $ category__Bar_furniture                      <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1…
## $ category__Beds                               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__Bookcases_&_shelving_units`       <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__Cabinets_&_cupboards`             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category__Café_furniture                     <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category__Chairs                             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__Chests_of_drawers_&_drawer_units` <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__Children's_furniture`             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category__Nursery_furniture                  <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category__Outdoor_furniture                  <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__Sofas_&_armchairs`                <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__Tables_&_desks`                   <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__TV_&_media_furniture`             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category__Wardrobes                          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `category__-OTHER`                           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `price__-Inf_5.84354441703136`               <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1…
## $ price__5.84354441703136_6.75693238924755     <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ price__6.75693238924755_7.52023455647463     <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ price__7.52023455647463_Inf                  <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ sellable_online__TRUE                        <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1…
## $ `sellable_online__-OTHER`                    <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ other_colors__No                             <dbl> 0, 1, 1, 1, 1, 1, 1, 1, 1…
## $ other_colors__Yes                            <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `depth__-Inf_40`                             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ depth__40_48                                 <dbl> 0, 0, 1, 1, 1, 1, 1, 1, 1…
## $ depth__48_66                                 <dbl> 1, 1, 0, 0, 0, 0, 0, 0, 0…
## $ depth__66_Inf                                <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `height__-Inf_74`                            <dbl> 0, 1, 0, 0, 0, 0, 0, 0, 0…
## $ height__74_95                                <dbl> 0, 0, 1, 1, 1, 1, 1, 0, 0…
## $ height__95_180.75                            <dbl> 1, 0, 0, 0, 0, 0, 0, 1, 1…
## $ height__180.75_Inf                           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ `width__-Inf_60`                             <dbl> 1, 0, 1, 1, 1, 1, 1, 1, 1…
## $ width__60_100                                <dbl> 0, 1, 0, 0, 0, 0, 0, 0, 0…
## $ width__100_180                               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ width__180_Inf                               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0…
# Correlate
corr_tbl <- binarized_table %>%
    correlate(price__7.52023455647463_Inf)

corr_tbl
## # A tibble: 35 × 3
##    feature  bin                               correlation
##    <fct>    <chr>                                   <dbl>
##  1 price    7.52023455647463_Inf                    1    
##  2 width    180_Inf                                 0.610
##  3 depth    66_Inf                                  0.418
##  4 width    -Inf_60                                -0.356
##  5 category Sofas_&_armchairs                       0.343
##  6 price    -Inf_5.84354441703136                  -0.335
##  7 price    6.75693238924755_7.52023455647463      -0.333
##  8 price    5.84354441703136_6.75693238924755      -0.332
##  9 category Wardrobes                               0.302
## 10 height   -Inf_74                                -0.283
## # ℹ 25 more rows
# Step 3: Plot Correlation Funnel
corr_tbl %>%
    plot_correlation_funnel()
## Warning: ggrepel: 12 unlabeled data points (too many overlaps). Consider
## increasing max.overlaps

Product Category

data %>%
  ggplot(aes(price, as.factor(category))) +
  geom_boxplot()

category <- data %>%
    select(price, category)

# Calculate average price per category
category_avg_price <- category %>%
  group_by(category) %>%
  summarise(avg_price = mean(price, na.rm = TRUE)) %>%
  ungroup()

# Plot bar chart of average prices per category
ggplot(category_avg_price, aes(x = reorder(category, avg_price), y = avg_price)) +
  geom_bar(stat = "identity", fill = "skyblue", color = "black") +
  labs(title = "Average Price per Product Category",
       x = "Product Category",
       y = "Average Price (log-transformed)") +
  theme_minimal() + 
  theme(axis.text.x = element_text(angle = 45, hjust = 1))

# Other colors available?

data %>%
  ggplot(aes(price, as.factor(other_colors))) +
  geom_boxplot()

Products sold online?

data %>%
  ggplot(aes(price, sellable_online)) +
  geom_boxplot()

Description correlation to price?

Graph below show the correlation of the short description of the products and their short description.

data %>%
  # Ensure short_description is character type
  mutate(short_description = as.character(short_description)) %>%
  
  # Tokenize short descriptions
  unnest_tokens(output = word, input = short_description) %>%
  
  # Calculate average price per word
  group_by(word) %>%
  summarise(price = mean(price, na.rm = TRUE), 
            n     = n()) %>%
  ungroup() %>%
  
  # Filter meaningful words
  filter(n > 10, !str_detect(word, "\\d")) %>%
  slice_max(order_by = price, n = 20) %>%
  
  # Plot
  ggplot(aes(price, fct_reorder(word, price))) +
  geom_point() + 
  
  labs(y = "Words in Short Description", 
       x = "Average Price when Word is Included")

#Build Models

# data <- sample_n(data, 100)

set.seed(1234)
ikea_split <- rsample::initial_split(data, prop = 0.75)
ikea_train <- training(ikea_split)
ikea_test <- testing(ikea_split)
# Specify recipe
ikea_recipe <- 
    recipe(price ~ ., data = ikea_train) %>%
    update_role(item_id, new_role = "id variable") %>%
    step_tokenize(short_description) %>%
    step_tokenfilter(short_description, max_tokens = 100) %>%
    step_tfidf(short_description) %>%
    step_other(category) %>%
    step_dummy(all_nominal_predictors(), one_hot = TRUE) %>%
    step_YeoJohnson(width, height, depth) %>%
    step_impute_knn(all_predictors())

ikea_recipe %>% prep() %>% juice() %>% glimpse()
## Rows: 2,035
## Columns: 117
## $ item_id                                   <dbl> 9219527, 99248380, 59157555,…
## $ depth                                     <dbl> 4.816575, 4.055862, 4.896875…
## $ height                                    <dbl> 13.192531, 15.758387, 20.498…
## $ width                                     <dbl> 5.949197, 10.244117, 8.93084…
## $ price                                     <dbl> 4.595120, 6.897705, 7.338238…
## $ tfidf_short_description_1                 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_100x60x236        <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_150x44x236        <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_150x58x201        <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_150x60x201        <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_150x60x236        <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_150x66x236        <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_2                 <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_200x60x236        <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_200x66x236        <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_3                 <dbl> 0.0000000, 0.5114545, 0.8524…
## $ tfidf_short_description_35x35x35          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_4                 <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_41x101            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_41x61             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_5                 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_6                 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_60x50x128         <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_61x101            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_63                <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_74                <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_76                <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_8                 <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_80x200            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_80x30x202         <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_90                <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_90x200            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_add               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_and               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_armchair          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_armrest           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_armrests          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_backrest          <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_bar               <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_baskets           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_bed               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_bedside           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_bench             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_bookcase          <dbl> 0.000, 0.000, 0.000, 0.000, …
## $ tfidf_short_description_cabinet           <dbl> 0.0000000, 0.5407864, 0.0000…
## $ tfidf_short_description_castors           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_chair             <dbl> 2.684967, 0.000000, 0.000000…
## $ tfidf_short_description_chaise            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_changing          <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_chest             <dbl> 0.0000000, 0.0000000, 0.0000…
## $ `tfidf_short_description_children's`      <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_cm                <dbl> 0.0000000, 0.1776674, 0.2961…
## $ tfidf_short_description_combination       <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_corner            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_cover             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_day               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_desk              <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_door              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_doors             <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_drawer            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_drawers           <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_feet              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_foldable          <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_for               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_frame             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_glass             <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_highchair         <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_in                <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_inserts           <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_junior            <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_leg               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_legs              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_lock              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_longue            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_mesh              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_modular           <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_module            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_mounted           <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_of                <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_on                <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_outdoor           <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_panel             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_plinth            <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_seat              <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_section           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_sections          <dbl> 0.0000000, 0.7998332, 1.3330…
## $ tfidf_short_description_shelf             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_shelves           <dbl> 0.0000000, 0.7666921, 0.0000…
## $ tfidf_short_description_shelving          <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_side              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_sliding           <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_smart             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_sofa              <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_stool             <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_storage           <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_table             <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_top               <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_tv                <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_unit              <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_upright           <dbl> 0.000000, 0.000000, 0.000000…
## $ tfidf_short_description_w                 <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_wall              <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_wardrobe          <dbl> 0.0000000, 0.0000000, 0.0000…
## $ tfidf_short_description_wire              <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ tfidf_short_description_with              <dbl> 0.0000000, 0.0000000, 0.0000…
## $ category_Beds                             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category_Bookcases...shelving.units       <dbl> 0, 1, 0, 0, 1, 0, 0, 0, 0, 1…
## $ category_Cabinets...cupboards             <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category_Chairs                           <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 1, 0…
## $ category_Chests.of.drawers...drawer.units <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category_Sofas...armchairs                <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ category_Wardrobes                        <dbl> 0, 0, 1, 0, 0, 0, 0, 1, 0, 0…
## $ category_other                            <dbl> 0, 0, 0, 1, 0, 1, 1, 0, 0, 0…
## $ sellable_online_FALSE.                    <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ sellable_online_TRUE.                     <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
## $ other_colors_No                           <dbl> 1, 1, 1, 1, 1, 1, 1, 0, 1, 0…
## $ other_colors_Yes                          <dbl> 0, 0, 0, 0, 0, 0, 0, 1, 0, 1…
# Specify model
xgboost_spec <- 
    boost_tree(trees = tune(), min_n = tune(), mtry = tune(), learn_rate = tune()) %>%
    set_mode("regression") %>%
    set_engine("xgboost")

# Combine recipe and model using workflow
xgboost_workflow <-
    workflow() %>%
    add_recipe(ikea_recipe) %>%
    add_model(xgboost_spec)

# Create cross-validation folds
set.seed(2345)
ikea_cv <- vfold_cv(ikea_train, v = 5)

# Perform hyperparameter tuning
set.seed(3456)
xgboost_tune <-
    tune_grid(
        xgboost_workflow, 
        resamples = ikea_cv, 
        grid = 5
    )
## i Creating pre-processing data to finalize unknown parameter: mtry