# This Week on CenterStat Unscripted: An Introduction to the Latent Curve Model

This Thursday at noon (2/23, 12:00 pm ET), Dan and Patrick will bicker their way through an introduction to the latent curve model (LCM), a type of structural equation model commonly used to analyze change over time. They begin by discussing two time-point longitudinal models, and then extend this to three or more time points. They describe the theoretical concept of an individual growth trajectory and explore how latent factors can be defined to estimate growth trajectories using repeated measures data. They then discuss incorporating time-invariant and time-varying predictors and conclude with a brief survey of more advanced models and applications.

Please join in on the fun at https://www.youtube.com/@centerstat/streams, or by following the link on the Unscripted webpage at https://centerstat.org/unscripted/.

For those who can’t catch the live broadcasts, a recording of each episode is posted to the CenterStat YouTube Channel. We can’t promise the recordings will be any more entertaining, but at least you can watch them at double-speed.

## What exactly qualifies as intensive longitudinal data and why am I not able to use more traditional growth models to study stability and change over time?

This post considers the unique features of intensive longitudinal data (ILD) relative to other more traditional data structures and how we can appropriately analyze ILD given these features

## My advisor told me I should group-mean center my predictors in my multilevel model because it might “make my effects significant” but this doesn’t seem right to me. What exactly is involved in centering predictors within the multilevel model?

How to specify multilevel models to obtain within- and between-group effects through centering lower-level predictors.

## I fit a multilevel model and got the warning message “G Matrix is Non-Positive Definite.” What does this mean and what should I do about it?

Received the cryptic warning message “G matrix is non-positive definite”? Learn what this means and what to do about it.

## Announcing CenterStat Unscripted: A New Weekly YouTube Livestream on Quantitative Methods

In large part because Dan and Patrick have jobs from which they can’t be fired, they keep coming up with random activities with which to…

## How can I define nonlinear trajectories in a growth curve model?

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,…