What is data imputation using k-nearest neighbors?

What is data imputation using k-nearest neighbors?

Data imputation using k-nearest neighbors is a technique used in data preprocessing to fill in missing values in a dataset. It involves finding the k nearest neighbors of a data point with missing values and using their known values to estimate and impute the missing values. The algorithm calculates the distance between the data point with missing values and its neighbors, and then assigns weights to the neighbors based on their proximity. These weighted values are then used to impute the missing values, providing a more complete dataset for further analysis.