Exercise

kNN tricks & tips I: weighting donors

A variation of kNN imputation that is frequently applied uses the so-called distance-weighted aggregation. What this means is that when we aggregate the values from the neighbors to obtain a replacement for a missing value, we do so using the weighted mean and the weights are inverted distances from each neighbor. As a result, closer neighbors have more impact on the imputed value.

In this exercise, you will apply the distance-weighted aggregation while imputing the tao data. This will only require passing two additional arguments to the kNN() function. Let's try it out!

Instructions

100 XP
  • Load the VIM package.
  • Impute humidity with kNN using distance-weighted mean for aggregating neighbors; you will need to specify the numFun and weightDist arguments.
  • The margin plot to view the results has been already coded for you.