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#0091

Clean Missing Values in R

EasyR12 min10 XP

Problem

Given scores <- c(10, NA, 20, NA, 30), replace NA values with the mean of non-missing values.

Why This Matters

Missing data appears constantly. R makes missing values explicit with NA, but many functions need na.rm = TRUE.

Examples

Example 1
Inputc(10, NA, 20, NA, 30)
Outputc(10, 20, 20, 20, 30)

The non-missing mean is 20.

Constraints

  • Use is.na.
  • Use na.rm = TRUE.
  • Replace only missing values.
CodeR
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Mean imputation
Inputscores with NA
ExpectedNA values become 20

Mean is computed only from observed scores.

Hidden Test Categories
no missing valuesone missing valueall missing values discussion