Detection Boundaries for Panel Slope Homogeneity Tests Under Small-Group Heterogeneity
小群体异质性下的面板斜率同质性检验检测边界
Empirical researchers often use slope-homogeneity tests to assess whether slopes can be treated as common across units. A key difficulty is that heterogeneity may be concentrated in a small number of units, so that a failure to reject homogeneity may reflect limited power rather than true homogeneity. We quantify this issue by analyzing the power of standard slope-homogeneity tests under doubly local alternatives - alternatives in which only small groups of units depart from…