Missing data are a common problem faced by nearly all data analysts, particularly with the increasing emphasis on the collection of repeated assessments over time.…
The issue of reliability can be a complex and often misunderstood issue. Entire text books have been written about reliability, validity, and scale construction, so…
This is a question that often arises when using structural equation models in practice, sometimes once a study is completed but more often in the…
This is a great question and is one that prompts much disagreement among quantitative methodologists. Nearly all confirmatory factor analysis or structural equation models impose…
This is a question we often hear, particularly from students and junior researchers who don’t have access to sometimes expensive commercial software for fitting structural…
We have worked with statistical models for longitudinal data for more than two decades and this remains a vexing question to us both. There are…
This very common question reflects a great deal of unnecessary confusion about how to select a specific analytic approach for modeling longitudinal data. The general…
Growth curve models, whether estimated as a multilevel model (MLM) or a structural equation model (SEM), have become widely used in many areas of behavioral,…
Continuous distributions are typically described by their mean (central tendency), variance (spread), skew (asymmetry), and kurtosis (thickness of tails). A normal distribution assumes a skew…
This is one of the most common questions we receive and, unfortunately, there are no quick answers. However, there are some initial guidelines that can…
