Cleaning disguised missing data
Hua Ming, Jian Pei · 2007
In some applications such as filling in a customer information form on the web, some missing values may not be explicitly represented as such, but instead appear as potentially valid data values. Such missing values are known as disguised missing data, which may impair the quality of data analysis severely, such as causing significant biases and misleading results in hypothesis tests, correlation analysis and regressions. The very limited previous studies on cleaning disguised missing data use outlier mining and distribution anomaly detection. They highly rely on domain background knowledge in specific applications and may not work well for the cases where the disguise values are inliers.