Analysis of group means 1 Bias 1 Correlation of Data 1 Group-level outcomes Humans 1 Least-Squares Analysis 1 Micro–macro data 1 Multilevel Analysis 1 Observer Variation 1 Reproducibility of Results 1 Sample Size 1 analytic method 1 article 1 controlled study 1 effect size 1 error 1 human 1 least square analysis 1 multilevel analysis 1 observer variation 1 outcome assessment 1 outcome variable 1 predictor variable 1 reliability 1 reproducibility 1 sample size 1 scientist 1 simulation 1 statistical bias 1