# findRMSEAsamplesize: Find the minimum sample size for a given statistical power... In semTools: Useful Tools for Structural Equation Modeling

 findRMSEAsamplesize R Documentation

## Find the minimum sample size for a given statistical power based on population RMSEA

### Description

Find the minimum sample size for a specified statistical power based on population RMSEA. This function can be applied for both test of close fit and test of not-close fit (MacCallum, Browne, & Suguwara, 1996)

### Usage

```findRMSEAsamplesize(rmsea0, rmseaA, df, power = 0.8, alpha = 0.05, group = 1)
```

### Arguments

 `rmsea0` Null RMSEA `rmseaA` Alternative RMSEA `df` Model degrees of freedom `power` Desired statistical power to reject misspecified model (test of close fit) or retain good model (test of not-close fit) `alpha` Alpha level used in power calculations `group` The number of group that is used to calculate RMSEA.

### Details

This function find the minimum sample size for a specified power based on an iterative routine. The sample size keep increasing until the calculated power from `findRMSEApower` function is just over the specified power. If `group` is greater than 1, the resulting sample size is the sample size per group.

### Author(s)

Sunthud Pornprasertmanit (psunthud@gmail.com)

### References

MacCallum, R. C., Browne, M. W., & Sugawara, H. M. (1996). Power analysis and determination of sample size for covariance structure modeling. Psychological Methods, 1(2), 130–149. doi: 10.1037/1082-989X.1.2.130

Jak, S., Jorgensen, T. D., Verdam, M. G., Oort, F. J., & Elffers, L. (2021). Analytical power calculations for structural equation modeling: A tutorial and Shiny app. Behavior Research Methods, 53, 1385–1406. doi: 10.3758/s13428-020-01479-0

• `plotRMSEApower` to plot the statistical power based on population RMSEA given the sample size

• `plotRMSEAdist` to visualize the RMSEA distributions

• `findRMSEApower` to find the statistical power based on population RMSEA given a sample size

### Examples

```
findRMSEAsamplesize(rmsea0 = .05, rmseaA = .08, df = 20, power = 0.80)

```

semTools documentation built on May 10, 2022, 9:05 a.m.