The Borrower Income Ratio

The borrower income ratio is the ratio of the borrower’s (or borrowers’) annual income to the median family income of the area for the reporting year. This is the ratio used to determine whether borrower’s income qualifies for an income-based housing goal.

In the data set mort, missing values are recoded as 9. In this exercise, we replaced the 9's in the "borrower_income_ratio" column with NA, so you can create a table of the borrower income ratios.

This exercise is part of the course

Scalable Data Processing in R

View Course

Exercise instructions

Load the biganalytics and dplyr packages.
Call summary() on mort to check that "borrower_income_ratio" now has NAs.
Using bigtable(), create a table of borrower income ratios for each year.
Use dplyr's mutate() to add a new column BIR.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Load biganalytics and dplyr packages
___
___

# Call summary on mort
___

bir_df_wide <- ___(mort, c(___, "year")) %>% 
    # Turn it into a data.frame
    as.data.frame() %>% 
    # Create a new column called BIR with the corresponding table categories
    ___(BIR = c(">=0,<=50%", ">50, <=80%", ">80%"))

bir_df_wide

Edit and Run Code