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Summarizing opportunity cost (1)

As you saw in the video, we're interested in whether the treatment and control groups were equally likely to buy a DVD after reading the experimental statements.

In this exercise, you'll use the data from the study to find the sample statistics (here: proportions) that are needed for the analysis.

This exercise is part of the course

Foundations of Inference in R

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Exercise instructions

  • Use the count() function to tabulate the dataset called opportunity. Make a note of the values in the decision column for use in the next step.
  • For each experimental group, find the proportion who bought a DVD. That is, calculate the mean where decision is "buyDVD".

Hands-on interactive exercise

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

# Tabulate the data
opportunity %>%
  ___(decision, group)

# Find the proportion who bought the DVD in each group
opportunity %>%
  group_by(___) %>%
  summarize(buy_prop = ___(___))
Edit and Run Code