During imputation we replace missing data with substituted values. The two types of imputation techniques involve are
Single Imputation :
* Hot-deck imputation : A missing value is imputed from a randomly selected similar record by the help of punch card
* Cold deck imputation : It works same as hot deck imputation, but it is more advanced and selects donors from another datasets
* Mean imputation : It involves replacing missing value with the mean of that variable for all other cases
* Regression imputation : It involves replacing missing value with the predicted values of a variable based on other variables
* Stochastic regression : It is same as regression imputation, but it adds the average regression variance to regression imputation
Multiple Imputation :
* Unlike single imputation, multiple imputation estimates the values multiple times
