ANOVA Assumption of Independence

Posted by Jignesh Sutar on Apr 19, 2013; 8:13am
URL: http://spssx-discussion.165.s1.nabble.com/ANOVA-Assumption-of-Independence-tp5719551.html

Hi,

 

Not strictly a SPSS question but a stats question instead, hoping it may take interest to others and elicit a response from any one of the list members.

 

Suppose I have multiple records per student, for simplicity say 3 records per student, each record representing each of their A-Levels undertaken in secondary school. Suppose each A-Level is taught by a single teacher and data is collected on the age of the teacher (or years of experience of teacher – essentially an interval measure) and also a dichotomous variable indicating pass or failure of the A-level.

 

Would it be valid to use an ANOVA to test if the mean age (or years of experience of teacher) is different between the 2 groups (Pass vs. Failure).

 

One of three assumptions of ANOVA is that the groups must be independent. What I describe above  instinctively feels like this assumption is violated. So if ANOVA cannot be used, how should I be analyzing this data to answer this same questions?

 

Many thanks in advance.

Jignesh