levene.test {car} | R Documentation |
Computes Levene's test for homeogeneity of variance across groups.
levene.test(y, ...) ## S3 method for class 'formula': levene.test(y, ...) ## S3 method for class 'lm': levene.test(y, ...) ## Default S3 method: levene.test(y, group, ...)
y |
response variable for the default method, or lm or
formula object. If y is a linear-model object or a formula,
the variables on the right-hand-side of the model must all be factors and
must be completely crossed. |
group |
factor defining groups. |
... |
arguments to be passed down, e.g., data for the
formula and lm methods. |
returns an object meant to be printed showing the results of the test.
adapted from a response posted by Brian Ripley to the R-help email list.
John Fox jfox@mcmaster.ca; generic version contributed by Derek Ogle
Fox, J. (1997) Applied Regression, Linear Models, and Related Methods. Sage.
with(Moore, levene.test(conformity, fcategory)) ## Levene's Test for Homogeneity of Variance ## Df F value Pr(>F) ## group 2 0.046 0.9551 ## 42 with(Moore, levene.test(conformity, interaction(fcategory, partner.status))) ## Levene's Test for Homogeneity of Variance ## Df F value Pr(>F) ## group 5 1.4694 0.2219 ## 39 levene.test(conformity ~ fcategory*partner.status, data=Moore) levene.test(lm(conformity ~ fcategory*partner.status, data=Moore))