In Born together—Reared apart: the Landmark Minnesota twin study (2012), Nancy Segal discusses the efforts of research psycholog
ists at the University of Minnesota to understand similarities and differences between twins by studying sets of twins who were raised separately. Below are critical reading SAT scores for several pairs of identical twins (twins who share all of their genes), one of whom was raised in a family with no other children (no siblings) and one of whom was raised in a family with other children (with siblings). A. What is the mean difference between the critical reading SAT scores for the twins raised with no siblings and the twins raised with siblings?
B. Provide a 90% confidence interval estimate of the mean difference between the critical reading SAT scores for the twins raised with no siblings and the twins raised with siblings.
C. Conduct a hypothesis test of equality of the critical reading SAT scores for the twins raised with no siblings and the twins raised with siblings. What is the p-value?
The answer is 0.9 Because the scatter plot is a positive liner relationship the answer would have to be positive but the liner relationship is not perfect so the value would not be 1.
To round to the nearest thousand, you look at the number to the right of 5. If the number is 5 or higher then you round 5 up. But it is 4 so you keep 5 the same. All of the numbers after 5 are now 0. 705,000