Data Collectionhard
0:00.0

A researcher compares two diet programs (Diet X vs. Diet Y) using a matched pairs design with 50 pairs of volunteers matched on age, baseline weight, and metabolism. Correlation of weight loss between matched partners: ρ=0.74\rho = 0.74.

Compared to an independent-groups design with 50 participants per diet (100 total), the matched pairs design achieves approximately how many times the statistical power to detect an equal effect size?