Missing Data — Definition

Definition

Missing-data reasoning uses the relationships supplied in a table, chart or statement to determine an unknown value, a range or whether a unique answer is possible. Totals, averages, percentages and ratios can provide equations linking the entries.

A blank cell is not automatically zero, and a plausible-looking pattern is not evidence unless the problem specifies it. The method is to label unknowns, translate each independent condition into an equation and check the result against units and domain restrictions.

Sometimes the requested total is determined even when individual entries remain unknown.