multilevel (version 2.5)

ICC1: Function to Estimate Intraclass Correlation Coefficient 1 or ICC(1) from an aov model

Description

This function calculates the Intraclass Correlation Coefficient 1 or ICC(1) from an ANOVA model. This value is equivalent to the ICC discussed in the random coefficient modeling literature, and represents the amount of individual-level variance that can be "explained" by group membership.

Usage

ICC1(object)

Arguments

object

An ANOVA (aov) object from an one-way analysis of variance.

Value

References

Bliese, P. D. (2000). Within-group agreement, non-independence, and reliability: Implications for data aggregation and Analysis. In K. J. Klein & S. W. Kozlowski (Eds.), Multilevel Theory, Research, and Methods in Organizations (pp. 349-381). San Francisco, CA: Jossey-Bass, Inc.

Bartko, J.J. (1976). On various intraclass correlation reliability coefficients. Psychological Bulletin, 83, 762-765.

See Also

ICC2 aov

Examples

   data(bh1996)
   hrs.mod<-aov(HRS~as.factor(GRP),data=bh1996)
   ICC1(hrs.mod)