Essay 1
A group of researchers conducted an experiment to determine which vaccine is more effective for preventing getting the flu. They tested two different types of vaccines: a shot and a nasal spray. To test the effectiveness, 1000 participants were randomly selected with 500 people getting the shot and 500 the nasal spray. Of the 500 people were treated with the shot, 80 developed the flu and 420 did not. Of the people who were treated with the nasal spray, 120 people developed the flu and 380 did not. The level of significance was set at .05. The proportion of people who were treated with the shot who developed the flu = .16, and the proportion of the people who were treated with the nasal spray was .24. The calculated p value = .0008.

describe the statistical approaches, Interpret the statistical results and examine the limitations of the statistical methods.
Essay 2
A researcher has investigated the relationship between IQ and grade point average (GPA) and found the correlation to be .75.
critique the results and interpretation of a correlational study.

Essay 3
A researcher has recorded the reaction times of 20 individuals on a memory assessment. The following table indicates the individual times:

2.2 4.7 7.3 4.1
9.5 15.2 4.3 9.5
2.7 3.1 9.2 2.9
8.2 7.6 3.5 2.5
9.3 4.8 8.5 8.1
calculate basic descriptive statistics, interpret the results, and evaluate the effects of outliers and changes in the variables.