4.20 Can children estimate their own reading ability? To study this question, investigators asked 60 fifth-grade children to estimate their own reading ability, on a scale from 1 (low) to 5 (high). Figure 4.7 is a scatterplot of the children's estimates

(response) against their scores on a reading test (explanatory).^

Both scores take only whole-number values.

(a) Is there an overall positive association between reading score and self-estimate?

(b) There is one clear outlier. What is this child's selfestimated reading level? Does this over- or underestimate the level as measured by the test?

Child's self-estimate of reading ability 0 20 40 60 80 Child's score on a test of reading ability 100