First, we limited the analysis to members with at least two baseline years of data to better control for possible regression to the mean
The identification of a similar comparison group limits the threats of history, maturation, and regression to the mean
that are common to observational studies lacking such a comparison.
The second internal validity concern is regression to the mean
This finding suggests that the observed improvement on the competencies selected for development was significantly greater than explained by regression to the mean
Changes in biochemical markers of bone turnover in women treated with raloxifene: influence of regression to the mean
Even so, it seems unlikely that regression to the mean
is the entire story, even in reading.
If it is less than one, we have regression to the mean
across generations, a necessary, but not sufficient, condition for inequality (measured by the variance of In y) to decline over time.
And as Bellos put it: "A best-ever result is comparable to an extreme event, and regression to the mean
says that after an extreme event the likelihood is of one less extreme.
The two central issues he focused on were the potential bias introduced by regression to the mean
and the confounding effects of stigma, or the "scarlet letter" (Carnoy 2001: 22) of receiving failing grades from the state.
September 10: Modeling and simulation to adjust p-values in presence of a regression to the mean
The same reasoning applies to the threat of bias because of history, regression to the mean
, or external environmental influences.
Ornish admitted that there was some regression to the mean
but added, "there is a direct correlation between degree of adherence and outcomes at 1 year.
Krueger and Funder hold that the results are undermined by a statistical effect known as regression to the mean
Observed crash data are subject to regression to the mean
, because high short-term crash frequencies are likely to decrease and low short-term crash frequencies are likely to increase as a matter of course, even if no improvements are made.
The study, believed to be the first of its kind in the industry, used statistically sound methodology that eliminates aberrations such as selection bias, regression to the mean
and demographic differences.