S4E14 Growth Trajectory Estimates…What’s My Line?


In this week’s episode Greg and Patrick explore all the ways they lie about things when they teach, not the least of which is that there are actually no individual growth trajectories estimated in an individual trajectory growth model. They discuss why this is, how individual trajectory estimates can be obtained, and how these might be used in practice. Along the way they also discuss the green light button, developmental milestones, love for semicolons, Jack Nicholson, baskets of data, Oprah, it’s all crap, transparencies and dittos, yelling at your steering wheel, libertarians vs. socialists, carts and donkeys, catching squirrels, enemy on the field, being stung, bit, and chased, and persnickety models.

Lightly Edited Transcript

We provide a lightly-edited and obviously imperfect audio transcript of the episode available here. This is not an exact representation of the audio, but does provide a searchable document with identified speakers and associated time stamps.

Related Episodes

S1E13: How Do I get Scale Scores? Weight, Weight….Don’t Tell Me….

S2E26: MLM vs. SEM: Opportunities for Growth

S2E21: Yes, Virginia… There ARE Latent Variables

Suggested Readings

Altman, N. S., & Casella, G. (1995). Nonparametric empirical Bayes growth curve analysis. Journal of the American Statistical Association90(430), 508-515.

Carrig, M. M., Wirth, R. J., & Curran, P. J. (2004). A SAS macro for estimating and visualizing individual growth curves. Structural Equation Modeling11, 132-149. [macro code] [user manual]

Gopen, G. D., & Swan, J. A. (1990). The science of scientific writing. American Scientist, 78, 550–558.

Raudenbush, S. W., & Bryk, A. S. (2002). Hierarchical linear models: Applications and data analysis methods (Vol. 1). Sage.

Seltzer, M. H., Wong, W. H., & Bryk, A. S. (1996). Bayesian analysis in applications of hierarchical models: Issues and methods. Journal of Educational and Behavioral Statistics21, 131-167.

Strenio, J. F., Weisberg, H. I., & Bryk, A. S. (1983). Empirical Bayes estimation of individual growth-curve parameters and their relationship to covariates. Biometrics, 71-86.


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