Studies suggest that when young men interact with a woman who is in the fertile period of her menstrual cycle, they pick up subconsciously on subtle changes in her skin tone, voice, and scent. A study introduced in Exercise B.18 suggests that men may even change their speech patterns around ovulating women. The men were randomly divided into two groups with one group paired with a woman in the fertile phase of her cycle and the other group with a woman in a different stage of her cycle. The same women were used in the two different stages. For the men paired with a less fertile woman, 38 of the 61 men copied their partner’s sentence construction in a task to describe an object. For the men paired with a woman at peak fertility, 30 of the 62 men copied their partner’s sentence construction. The experimenters hypothesized that men might be less likely to copy their partner during peak fertility in a (subconscious) attempt to attract more attention to themselves. Use the normal distribution to test at a 5% level whether the proportion of men copying sentence structure is less when the woman is at peak fertility.

Exercise B.18

Studies suggest that when young men interact with a woman who is in the fertile period of her menstrual cycle, they pick up subconsciously on subtle changes in her skin tone, voice, and scent. A new study suggests that they may even change their speech patterns. The experiment included 123 male and 5 female college students, all of them heterosexual. The men were randomly divided into two groups with one group paired with a woman in the fertile phase of her cycle and the other group with a woman in a different stage of her cycle. The women were used equally in the two different stages. For the men paired with a less fertile woman, 38 of the 61 men copied their partner’s sentence construction in a task to describe an object. For the men paired with a woman at peak fertility, 30 of the 62 men copied their partner’s sentence construction. The experimenters hypothesized that men might be less likely to copy their partner during peak fertility in a (subconscious) attempt to attract more attention to themselves. Use StatKey or other technology to create a randomization distribution and conduct a hypothesis test to see if the proportion copying sentence structure is less when the woman is at peak fertility. Include all details of the test. Are the results significant at a 5% level? Are they significant at a 10% level?