1. Most dermatologists recommend using sunscreens that have a sun protection factor (SPF) of at least 30. One of the authors wanted to find out whether the SPF of sunscreens used by students at her school (which is in a very sunny part of the U.S.) exceeds this value, on average? To collect data, the author surveyed students and found that in a random sample of 48 students the average SPF was 35.29 and the standard deviation of SPF was 17.19. Additionally, the sampling distribution wasn't strongly skewed.

1. State the variable of interest. Is this quantitative or categorical?

1. State the parameter. Assign a symbol.

1. State the statistic. Assign a symbol.

1. In symbols, what are the null and alternative hypotheses?

1. Justify why you can use the theory-based approach. Be specific!

1. Calculate the theory-based standardized statistic.

1. Based on our standardized statistic, we would ______________ the null hypothesis.
   1. Accept
   2. Fail to reject
   3. Reject

1. What is a conclusion in context of the research question.

1. Can you generalize your results to UNL students? Explain.

1. Which type of error could have occurred given your decision in part g? TYPE I / TYPE II

1. Explain in context the error that could have occurred given your results?

1. Normal (or average) body temperature of humans is often thought to be 98.6 F. Is that number really the average? To test this, we will use a data set obtained from 65 healthy female volunteers aged 18 to 40 that were participating in vaccine trials. The mean body temperature for the 65 females in our sample is 98.5 F and the standard deviation is 0.743 F. The sampling distribution is not strongly skewed.

1. State the variable of interest. Is this quantitative or categorical?

1. State the parameter. Assign a symbol.

1. State the statistic. Assign a symbol.

1. In symbols, what are the null and alternative hypotheses?

1. Justify why you can use the theory-based approach.

1. Calculate the theory-based standardized statistic.

1. Based on our standardized statistic, we would ______________ the null hypothesis.
   1. Accept
   2. Fail to reject
   3. Reject

1. What is a conclusion in context of the research question.

1. Can you generalize your results to all humans? Explain.

1. Which type of error could have occurred given your decision in part g? TYPE I / TYPE II

1. Explain in context the error that could have occurred given your results?