how to get an average measurement when data is missing when you add a student to a case what makes the data missing do you need parent data for all cases how to assemble parent data how to re-aggregate parent and teacher observations how do you get an average measurement based on two raters how to aggregate parent data how to get an average measurement how to use substitution in psychology how to calculate the average of the parents data how to get an average measurement using two raters for cases where data is missing for one rater? what is substitution in psychology which of the following is a method of substitution? when using parent data how many cases of the sample will the same statistic be used when is it necessary to aggregate parent and teacher data ________ would imply the parent score is missing can the parent and teacher score differ within the same sample? how to use an average score as a racing variable what does it mean for parents and teachers data to be merged does aggregating parent and child data make sense