It’s always a good idea to check the help information for a function before using it. Don’t necessarily assume a function will perform a test as you think it will. The help information will give the options available for that function, and often those options make a difference with how the test is carried out.
In order to see the help file for the chisq.test function:
In order to specify the chisq.test function in the stats package, you would use:
In order to search all installed packages for a term:
In order to view the help for a package
Documentation for packages are also available in a .pdf format, which may be more convenient than using the help within R. Also very helpful, some packages include vignettes, which describe how a package might be used.
For a list of available packages, visit cran.r-project.org/web/packages/available_packages_by_name.html.
And clicking on the link for the psych package, will bring up a page with a link for the .pdf documentation, two .pdf vignettes, and other information.
Summary and Analysis of Extension Education Program Evaluation in R
Most of the analyses in this book are also presented in Summary and Analysis of Extension Education Program Evaluation in R (SAEEPER). It may be useful for the reader to consult that book for additional examples and discussion.
Since there are many good resources for R online, an internet search for your question or analysis including the term “r” will often lead to a solution. The reader is cautioned, however, to always check the original R documentation on functions to be sure it will perform an analysis as the user desires.
A convenient tool is the RSiteSearch function, which will open a browser window and search for a term in functions and vignettes across a variety of sources:
This tool can also be accessed from: http://search.r-project.org/nmz.html.