Littlefield and Klein (2005) examined memory in children with a specific reading disorder. They theorized that reading is a complex memory task that requires children to associate meaning with what is initially a series of abstract squiggly lines. They tested the memory of children diagnosed with the same reading disorder (the RD group) and compared their memory scores with "normally achieving" (NA) children, matched for age and sex, family socioeconomic status, and region. Memory was tested using the Associate Memory (AM) test. A series of 15 black and white line drawings were presented, and the children were told a word to associate with each drawing. Later on, the same symbols were presented and the children were asked to remember the word associated with each one. Scores can range from 0 (meaning the children could not remember any of the words correctly) to 15 (all pairings were remembered correctly).

Associate Memory Test Scores

RD 2 2 3 3 5 5 7 8 9 10 sum=54 n=10,

NA 5 6 6 6 7 8 9 10 10 12 sum=79 n=10

a. What are the average scores on the AM test for both groups?

b. Calculate the range for both groups.

c. Calculate the standard deviation of the AM test scores for both groups.

d. Calculate the median and mode for the scores in both groups.

e. Calculate the 75th percentile for the AM test scores for both groups.

f. Is there support for the prediction that children with reading disorders would have poorer scores on the AM test compared to normal achieving age peers?