1. Do this problem by hand. A recent report in Science summarizing a large Norwegian study claimed that firstborn children have higher IQ's than later born children. To test the hypothesis that birth order influences IQ you decide to do a small study of your own. Thirteen of your friends volunteer to report their scores on a standardized test as well as scores for their siblings. Below is the data which can be assumed to be normally distributed.

First-born	Second-born
113	109
127	120
130	131
109	105
115	110
119	119
105	109
117	114
135	130
143	139
111	105
128	121
135	130

1. Does your data support the claims of the larger study reported in Science? (is the data independent?)

1. Reanalyze without making the assumption of normality for the data.