Table 13.14 shows the slope of the least-squares regression line for each of the eight subjects, as well as the score on the linear D variable, reproduced from Table 13.14. There is a strikin relationship between the numbers in the two columns of Table 13.14. Every subject's score on D is 24 times his or her slope.
References
Maxwell, S. E., Delaney, H. D., \& Kelley, K. (2018). Designing experiments and analyzing data:
A model comparison perspective (3rd ed.). New York, NY: Routledge.