What validity is Marvin questioning when he asks, "How strong was the effect?" after reading a study?

When Marvin asks, "How strong was the effect?" he is questioning statistical validity. This type of validity relates to how well the data support the conclusions drawn from the statistical analyses. It involves examining whether the effect observed in the study is significant and meaningful.

Statistical validity assesses whether the statistical methods used to analyze the data were appropriate and whether the results were interpreted correctly. If a study demonstrates strong statistical validity, it indicates that the effects observed are not likely due to chance and that the measures used to determine those effects were reliable.

In this context, Marvin's focus on the strength of the effect indicates he is concerned with the magnitude and significance of the findings, which directly aligns with the principles of statistical validity. Understanding this aspect is crucial for determining how robust and trustworthy the results of the research are in addressing the study's hypotheses.