Contents
How is ICC measured?
The ICC serves as a quantitative estimate of this aspect of reliability. Very generally speaking, the ICC is calculated as a ratio ICC = (variance of interest) / (total variance) = (variance of interest) / (variance of interest + unwanted variance).
Can intraclass correlation be negative?
The intraclass correlation will be negative whenever MSB < MSW. In other words, the intraclass correlation will be negative whenever the variability within groups exceeds the variability across groups. This means that scores in a group “diverge” relative to the noise present in the individuals.
What is an ICC in statistics?
In statistics, the intraclass correlation, or the intraclass correlation coefficient (ICC), is a descriptive statistic that can be used when quantitative measurements are made on units that are organized into groups. It describes how strongly units in the same group resemble each other.
How to re-analyze intraclass correlation ( ICC ) theory?
A re-analysis of intraclass correlation (ICC) theory is presented together with Monte Carlo simulations of ICC probability distributions. A partly revised and simplified theory of the single-score ICC is obtained, together with an alternative and simple recipe for its use in reliability studies.
What is the value of the intra class correlation coefficient?
1. Introduction The intra-class correlation coefficient (ICC) is a number, usually found to have a value between 0 and 1. It is a well-known statistical tool, applied for example in medical, psychological, biological and genetic research.
How is the ICC of an intraclass calculated?
Very generally speaking, the ICC is calculated as a ratio ICC = (variance of interest) / (total variance) = (variance of interest) / (variance of interest + unwanted variance).
Is the single score ICC used in reliability studies?
A partly revised and simplified theory of the single-score ICC is obtained, together with an alternative and simple recipe for its use in reliability studies. Our main, practical conclusion is that in the analysis of a reliability study it is neither necessary nor convenient to start from an initial choice of a specified statistical model.