Sunlight makes everyone feel better.. To test this claim, 30 college students receive special lights for their bedrooms that slowly turn on in the morning with imitation sunlight. The experiment takes place in January, when it is still dark out in the morning. Prior to participation, the students fill out a questionnaire to measure their general mood. The average score was 2.73 . After three weeks with the special light they fill in the questionnaire again. The average score this time was 3.13 . The standard deviation of the differences was 0.822 . Calculate a 95 confidence interval for the difference in average mood scores (after before).
a. (0.14, 0.66)
b. (0.09, 0.71)
c. (0.19, 0.61)
d. None of the above
Question 2
In each situation, indicate whether it would make more sense to find a confidence interval for the population parameter or to conduct a hypothesis test for a specific null value. If your answer is a hypothesis test, specify the null value that you would test. A high school teacher is interested to know if students who take a foreign language will get higher grades if their final exam is an oral exam instead of a written exam. The following year he asks all of the Spanish teachers to give their students an oral exam at the end of the course. The average exam score in the previous years was 68 (out of a possible 100 points).
Piaget’s Test for Egocentric Perspectives on Children
Performing a Urine Pregnancy Test Using the Enzyme Immunoassay Method
Prostate-specific antigen test.
Cylinder Power Balance Test
Distribution of sex chromosomes from generation to generation. All children receive an X chromosome
The Ames test, which screens compounds for potential mutagenicity