semTools (version 0.2-0)

plotRMSEApower: Plot power curves for RMSEA

Description

Plots power of RMSEA over a range of sample sizes

Usage

plotRMSEApower(rmsea0, rmseaA, df, nlow, nhigh, steps=1, alpha=.05)

Arguments

rmsea0

Null RMSEA

rmseaA

Alternative RMSEA

df

Model degrees of freedom

nlow

Lower sample size

nhigh

Upper sample size

steps

Increase in sample size for each iteration. Smaller values of steps will lead to more precise plots. However, smaller step sizes means a longer run time.

alpha

Alpha level used in power calculations

Value

• 1. plot
  Plot of power for RMSEA against a range of sample sizes

Details

This function creates plot of power for RMSEA against a range of sample sizes. The plot places sample size on the horizontal axis and power on the vertical axis. The user should indicate the lower and upper values for sample size and the sample size between each estimate ("step size") We strongly urge the user to read the sources below (see References) before proceeding. A web version of this function is available at: http://quantpsy.org/rmsea/rmseaplot.htm.

References

MacCallum, R. C., Browne, M. W., & Cai, L. (2006). Testing differences between nested covariance structure models: Power analysis and null hypotheses. Psychological Methods, 11, 19-35. MacCallum, R. C., Browne, M. W., & Sugawara, H. M. (1996). Power analysis and determination of sample size for covariance structure modeling. Psychological Methods, 1, 130-149. MacCallum, R. C., Lee, T., & Browne, M. W. (2010). The issue of isopower in power analysis for tests of structural equation models. Structural Equation Modeling, 17, 23-41. Preacher, K. J., Cai, L., & MacCallum, R. C. (2007). Alternatives to traditional model comparison strategies for covariance structure models. In T. D. Little, J. A. Bovaird, & N. A. Card (Eds.), Modeling contextual effects in longitudinal studies (pp. 33-62). Mahwah, NJ: Lawrence Erlbaum Associates. Steiger, J. H. (1998). A note on multiple sample extensions of the RMSEA fit index. Structural Equation Modeling, 5, 411-419. Steiger, J. H., & Lind, J. C. (1980, June). Statistically based tests for the number of factors. Paper presented at the annual meeting of the Psychometric Society, Iowa City, IA.

See Also

• plotRMSEAdistto visualize the RMSEA distributions
• findRMSEApowerto find the statistical power based on population RMSEA given a sample size
• findRMSEAsamplesizeto find the minium sample size for a given statistical power based on population RMSEA

Examples

plotRMSEApower(.025, .075, 23, 100, 500, 10)