Speed Up Exploratory Data Analysis (EDA)
The goal of correlationfunnel
is to speed up Exploratory Data Analysis
(EDA). Here’s how to use it.
You can install the latest stable (CRAN) version of correlationfunnel
with:
install.packages("correlationfunnel")
You can install the development version of correlationfunnel
from
GitHub with:
devtools::install_github("business-science/correlationfunnel")
Problem: Exploratory data analysis (EDA) involves looking at feature-target relationships independently. This process is very time consuming even for small data sets. Rather than search for relationships, what if we could let the relationships come to us?
Solution: Enter correlationfunnel
. The package provides a
succinct workflow and interactive visualization tools for
understanding which features have relationships to target (response).
Main Benefits:
-
Speeds Up Exploratory Data Analysis
-
Improves Feature Selection
-
Gets You To Business Insights Faster
The following example showcases the power of fast exploratory correlation analysis. The goal of the analysis is to determine which features relate to the bank’s marketing campaign goal of having customers opt into a TERM DEPOSIT (financial product).
We will see that using 3 functions, we can quickly:
-
Transform the data into a binary format with
binarize()
-
Perform correlation analysis using
correlate()
-
Visualize the highest correlation features using
plot_correlation_funnel()
Result: Rather than spend hours looking at individual plots of capaign features and comparing them to which customers opted in to the TERM DEPOSIT product, in seconds we can discover which groups of customers have enrolled, drastically speeding up EDA.
First, load the libraries.
library(correlationfunnel)
library(dplyr)
Next, collect data to analyze. We’ll use Marketing Campaign Data for a
Bank that was popularized by the UCI Machine Learning
Repository. We
can load the data with
data("marketing_campaign_tbl")
.
# Use ?marketing_campagin_tbl to get a description of the marketing campaign features
data("marketing_campaign_tbl")
marketing_campaign_tbl %>% glimpse()
#> Observations: 45,211
#> Variables: 18
#> $ ID <chr> "2836", "2837", "2838", "2839", "2840", "2841", "28…
#> $ AGE <dbl> 58, 44, 33, 47, 33, 35, 28, 42, 58, 43, 41, 29, 53,…
#> $ JOB <chr> "management", "technician", "entrepreneur", "blue-c…
#> $ MARITAL <chr> "married", "single", "married", "married", "single"…
#> $ EDUCATION <chr> "tertiary", "secondary", "secondary", "unknown", "u…
#> $ DEFAULT <chr> "no", "no", "no", "no", "no", "no", "no", "yes", "n…
#> $ BALANCE <dbl> 2143, 29, 2, 1506, 1, 231, 447, 2, 121, 593, 270, 3…
#> $ HOUSING <chr> "yes", "yes", "yes", "yes", "no", "yes", "yes", "ye…
#> $ LOAN <chr> "no", "no", "yes", "no", "no", "no", "yes", "no", "…
#> $ CONTACT <chr> "unknown", "unknown", "unknown", "unknown", "unknow…
#> $ DAY <dbl> 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, …
#> $ MONTH <chr> "may", "may", "may", "may", "may", "may", "may", "m…
#> $ DURATION <dbl> 261, 151, 76, 92, 198, 139, 217, 380, 50, 55, 222, …
#> $ CAMPAIGN <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, …
#> $ PDAYS <dbl> -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,…
#> $ PREVIOUS <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, …
#> $ POUTCOME <chr> "unknown", "unknown", "unknown", "unknown", "unknow…
#> $ TERM_DEPOSIT <chr> "no", "no", "no", "no", "no", "no", "no", "no", "no…
Modeling and Machine Learning problems often involve a response
(Enrolled in TERM_DEPOSIT
, yes/no) and many predictors (AGE, JOB,
MARITAL, etc). Our job is to determine which predictors are related to
the response. We can do this through Binary Correlation Analysis.
Binary Correlation Analysis is the process of converting continuous (numeric) and categorical (character/factor) data to binary features. We can then perform a correlation analysis to see if there is predictive value between the features and the response (target).
The first step is converting the continuous and categorical data into
binary (0/1) format. We de-select any non-predictive features. The
binarize()
function then converts the features into binary features.
-
Numeric Features: Are binned into ranges or if few unique levels are binned by their value, and then converted to binary features via one-hot encoding
-
Categorical Features: Are binned by one-hot encoding
The result is a data frame that has only binary data with columns
representing the bins that the observations fall into. Note that the
output is shown in the glimpse()
format. THere are now 80 columns that
are binary (0/1).
marketing_campaign_binarized_tbl <- marketing_campaign_tbl %>%
select(-ID) %>%
binarize(n_bins = 4, thresh_infreq = 0.01)
marketing_campaign_binarized_tbl %>% glimpse()
#> Observations: 45,211
#> Variables: 74
#> $ `AGE__-Inf_33` <dbl> 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0…
#> $ AGE__33_39 <dbl> 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ AGE__39_48 <dbl> 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0…
#> $ AGE__48_Inf <dbl> 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1…
#> $ JOB__admin. <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0…
#> $ `JOB__blue-collar` <dbl> 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ JOB__entrepreneur <dbl> 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0…
#> $ JOB__housemaid <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ JOB__management <dbl> 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ JOB__retired <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0…
#> $ `JOB__self-employed` <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ JOB__services <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1…
#> $ JOB__student <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ JOB__technician <dbl> 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 0…
#> $ JOB__unemployed <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ `JOB__-OTHER` <dbl> 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MARITAL__divorced <dbl> 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0…
#> $ MARITAL__married <dbl> 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1…
#> $ MARITAL__single <dbl> 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0…
#> $ EDUCATION__primary <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0…
#> $ EDUCATION__secondary <dbl> 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1…
#> $ EDUCATION__tertiary <dbl> 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0…
#> $ EDUCATION__unknown <dbl> 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0…
#> $ DEFAULT__no <dbl> 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1…
#> $ DEFAULT__yes <dbl> 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0…
#> $ `BALANCE__-Inf_72` <dbl> 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0…
#> $ BALANCE__72_448 <dbl> 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1…
#> $ BALANCE__448_1428 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0…
#> $ BALANCE__1428_Inf <dbl> 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ HOUSING__no <dbl> 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ HOUSING__yes <dbl> 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ LOAN__no <dbl> 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ LOAN__yes <dbl> 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ CONTACT__cellular <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ CONTACT__telephone <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ CONTACT__unknown <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ `DAY__-Inf_8` <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ DAY__8_16 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ DAY__16_21 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ DAY__21_Inf <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__apr <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__aug <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__feb <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__jan <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__jul <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__jun <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__mar <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__may <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ MONTH__nov <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__oct <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ MONTH__sep <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ `MONTH__-OTHER` <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ `DURATION__-Inf_103` <dbl> 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0…
#> $ DURATION__103_180 <dbl> 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1…
#> $ DURATION__180_319 <dbl> 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0…
#> $ DURATION__319_Inf <dbl> 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0…
#> $ `CAMPAIGN__-Inf_2` <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ CAMPAIGN__2_3 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ CAMPAIGN__3_Inf <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ `PDAYS__-1` <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ `PDAYS__-OTHER` <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ PREVIOUS__0 <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ PREVIOUS__1 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ PREVIOUS__2 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ PREVIOUS__3 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ PREVIOUS__4 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ PREVIOUS__5 <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ `PREVIOUS__-OTHER` <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ POUTCOME__failure <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ POUTCOME__other <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ POUTCOME__success <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
#> $ POUTCOME__unknown <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ TERM_DEPOSIT__no <dbl> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
#> $ TERM_DEPOSIT__yes <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
The second step is to perform a correlation analysis between the response (target = TERM_DEPOSIT_yes) and the rest of the features. This returns a specially formatted tibble with the feature, the bin, and the bin’s correlation to the target. The format is exactly what we need for the next step - Producing the Correlation Funnel
marketing_campaign_correlated_tbl <- marketing_campaign_binarized_tbl %>%
correlate(target = TERM_DEPOSIT__yes)
marketing_campaign_correlated_tbl
#> # A tibble: 74 x 3
#> feature bin correlation
#> <fct> <chr> <dbl>
#> 1 TERM_DEPOSIT no -1.000
#> 2 TERM_DEPOSIT yes 1.000
#> 3 DURATION 319_Inf 0.318
#> 4 POUTCOME success 0.307
#> 5 DURATION -Inf_103 -0.191
#> 6 PDAYS -OTHER 0.167
#> 7 PDAYS -1 -0.167
#> 8 PREVIOUS 0 -0.167
#> 9 POUTCOME unknown -0.167
#> 10 CONTACT unknown -0.151
#> # … with 64 more rows
A Correlation Funnel is an tornado plot that lists the highest correlation features (based on absolute magnitude) at the top of the and the lowest correlation features at the bottom. The resulting visualization looks like a Funnel.
To produce the Correlation Funnel, use plot_correlation_funnel()
.
Try setting interactive = TRUE
to get an interactive plot that can be
zoomed in on.
marketing_campaign_correlated_tbl %>%
plot_correlation_funnel(interactive = FALSE)
The most important features are towards the top. We can investigate these.
marketing_campaign_correlated_tbl %>%
filter(feature %in% c("DURATION", "POUTCOME", "PDAYS",
"PREVIOUS", "CONTACT", "HOUSING")) %>%
plot_correlation_funnel(interactive = FALSE, limits = c(-0.4, 0.4))
We can see that the following prospect groups have a much greater correlation with enrollment in the TERM DEPOSIT product:
-
When the DURATION, the amount of time a prospect is engaged in marketing campaign material, is 319 seconds or longer.
-
When POUTCOME, whether or not a prospect has previously enrolled in a product, is “success”.
-
When CONTACT, the medium used to contact the person, is “cellular”
-
When HOUSING, whether or not the contact has a HOME LOAN is “no”
The main addition of correlationfunnel
is to quickly expose feature
relationships to semi-processed data meaning missing (NA
) values have
been treated, date or date-time features have been feature engineered,
and data is in a “clean” format (numeric data and categorical data are
ready to be correlated to a Yes/No response).
Here are several great EDA packages that can help you understand data issues (cleanliness) and get data preprared for Correlation Analysis!
-
Data Explorer - Automates Exploration and Data Treatment. Amazing for investigating features quickly and efficiently including by data type, missing data, feature engineering, and identifying relationships.
-
naniar - For understanding missing data.
-
UpSetR - For generating upset plots
-
GGally - The
ggpairs()
function is one of my all-time favorites for visualizing many features quickly.
Business Science teaches students how to apply data science for business. The entire curriculum is crafted around business consulting with data science. Correlation Analysis is one of the many techniques that we teach in our curriculum. Learn from our data science application experience with real-world business projects.
Students learn by solving real world projects using our repeatable project-management framework along with cutting-edge tools like the Correlation Analysis, Automated Machine Learning, and Feature Explanation as part of our ROI-Driven Data Science Curriculum.
-
Learn Data Science Foundations (DS4B 101-R): Learn the entire
tidyverse
(dplyr
,ggplot2
,rmarkdown
, & more) andparsnip
- Solve 2 Projects - Customer Segmentation and Price Optimization projects -
Learn Advanced Machine Learning & Business Consulting (DS4B 201-R): Churn Project solved with Correlation Analysis,
H2O
AutoML,LIME
Feature Explanation, and ROI-driven Analysis / Recommendation Systems -
Learn Predictive Web Application Development (DS4B 102-R): Build 2 Predictive
Shiny
Web Apps - Sales Dashboard with Demand Forecasting & Price Prediction App