#missing values

2 bài viết

Cleaning Survey Data Before Analysis: Codebooks, Outliers and a Change Log

Many errors in quantitative papers sit in the data file, not the model: unreversed items, duplicates, an age of 250. A logged cleaning routine that lets you exp

24/09/2026 6 phút đọc

Phương pháp nghiên cứu

Secondary Data Analysis: Codebooks, Survey Weights and Traps in Existing Datasets

National survey datasets offer tens of thousands of households, free and already cleaned. Ignore the sampling weights, misread a missing-value code or merge wav

24/09/2026 7 phút đọc