Measures of Center Decision Guide Mean: use when every value should contribute and extremes are substantively relevant. Median: use for a resistant positional summary. Mode: use for the most frequent category or discrete value. Geometric mean: use for positive multiplicative growth factors. Trimmed mean: use only with a disclosed trimming rule. Midrange: use only when the endpoint midpoint answers the question. Original educational material created for STATLAB Academy. Do not reproduce third-party textbook content.