Welcome to cocron!

This is a website allowing to conduct statistical comparisons between Cronbach alpha coefficients. Click "Start analysis" to begin!

The calculations rely on the tests implemented in the package cocron for the R programming language. A detailed documentation of all tests is available here.

You can integrate the R code generated by this web interface in your own R script. To do so, you can download the cocron package from here or r-project.org. Alternatively, you can type one of the following commands in the R console to install:

# cran repository
install.packages("cocron", lib="/my/own/R-packages/")

# alternative repository
install.packages("cocron", lib="/my/own/R-packages/", repo="http://comparingcronbachalphas.org/repo")

The cocron package also includes a GUI extension for the R front-end RKWard, which you can use instead of this web interface.

Are the Cronbach alphas based on independent or on dependent groups? (If the data were taken from measurements of the same individuals, the groups are dependent.)

The Cronbach alphas are based on

Please make a choice!
Please provide the Cronbach alphas you want to compare and the sample sizes and number of items they are based on:
Cronbach's alpha Sample size Item count
1
2
Cronbach's alpha must be between 0 and 1!
The sample size must be an integer greater 0!
The item count must be an integer greater 0!
Please provide the Cronbach alphas you want to compare and the sample size and number of items they are based on:
Sample size: Item count:
Cronbach's alpha
1
2
Cronbach's alpha must be between 0 and 1!
The sample size must be an integer greater 0!
The item count must be an integer greater 0!
Please provide the correlations between the underlying scores of the Cronbach alphas:
The correlations must be between -1 and 1!
Please choose a level of significance for the test of significance:
Level of significance:
Please choose a level of confidence for the confidence intervals:
Level of confidence:
The level of significance must be between 0 and 1!
The level of confidence must be between 0 and 1!