Exercise

Preserving the most common levels

Sometimes you don't want to keep levels by proportion but instead the most common n levels. Let's see how the resulting levels kept for MLMethodNextYearSelect changes when we kept by number instead of proportion. multiple_choice_responses has been loaded for you.

Instructions

100 XP

Remove people who didn't select a method.
Create a new variable, ml_method, from MLMethodNextYearSelect that preserves 5 most common titles and lumps the rest as "other method" using the argument other_level.
Count the frequency of each ml_method, sorting in descending order.