"missing values" refer to the absence or lack of information in a dataset. It occurs when certain data points or variables are not recorded or are unknown. Full definition
We used complete case analysis because the proportion of missing values in the study population was small (5 % or less) for each regression variable. (journals.plos.org)
Two children had missing values on math self - concept and on verbal self - concept, and for one child our dependent variable was missing. (frontiersin.org)
The first introduces students to the bar model comparison diagrams and students have to find missing values. (tes.com)