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Joining question and answer counts

We can also determine how many questions actually yield answers. If we count the number of answers for each question, we can then join the answers counts with the questions table.

This exercise is part of the course

Joining Data with dplyr

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Exercise instructions

  • Count and sort the question_id column in the answers table to create the answer_counts table.
  • Join the questions table with the answer_counts table and include all observations from the questions table.
  • Replace the NA values in the n column with 0s.

Hands-on interactive exercise

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

# Count and sort the question id column in the answers table
answer_counts <- answers %>%
  ___

# Combine the answer_counts and questions tables
questions %>%
  ___ %>%
  # Replace the NAs in the n column
  ___
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