In this lab we will be conducting significance tests for population means and proportions.

1. Is the normal body temperature of a human less than 98.6 degrees?  After taking the temperature of his children many times, the author of this lab noticed that if his kids were well, their body temperature was always less than 98.6 degrees (what is often considered normal.)  In fact, if was often much less than 98.6.  He wondered if he just had "cool" kids or in fact what we think of as nomal was not.  Let's see if we can get statistics to answer this question.  A data set containing the body temperatures and heart rate for 65 men and 65 women can be found here.  We will use this data set to answer the questions:  "Is the mean human body temperature less than 98.6 degrees Fahrenheit?"

1. Make a histogram of the data. (Graph > Histogram > Simple)  Does 98.6 degrees appear to be in the center of the distribution, left of center, or right of center?
   
2. Find the mean and median body temperature for the 130 individuals. (Stat > Basic Statistics > Display Descriptive Statistics.) 
   
3. Based on your answers to the previous two questions, do you think that we can infer that the mean body temperature of all humans is less than 98.6 degrees?
   
4. Complete a t test to see if the mean body temperature for humans is less than 98.6 degrees Fahrenheit.  Report the hypotheses, t-statistic, P-value, and conclusion. (Stat > Basic Statistics > 1-Sample t.  Put Temp in the Sample from Columns box, 98.6 in the Test Mean box, and click on Options and choose less than for the alternative hypothesis.)  

2. For the next part of the lab, we will look at weights of coffee.  Ten samples of "half  pound" bags of hazelnut coffee from a local coffee house were weighed.  The results, in pounds, are found here.

1. Find the sample mean and standard deviation for the coffee data.
2. Using the coffee data, determine if the population mean of all hazelnut coffee has a mean weight less than the label weight of 0.5 pounds.  Report the hypotheses, t-statistic, P-value, and conclusion (write the conclusion out in words using no symbols.)  (Stat > Basic Statistics > 1-Sample t.  Put in 0.5 for the Test Mean, click on options and choose the appropriate alternative hypothesis.)
3. What is it about this coffee data set that made it more difficult to conclude the alternative hypothesis than with the body temperature data set?
   

3. Do you wash your hands after you use the restroom?  You probably should for many reasons.  But do most people?  Statistics students set out to find the answer.  They observed 76 people using public restrooms and found that 41 of them washed their hands.  Let's assume this is a simple random sample of all people using a public restroom.  (Perhaps this is a big assumption.)  In this sample, 34 were women and 23 of these washed their hands.

1. Determine if a majority of all people wash their hands after using a public restroom.  Report the hypotheses, P-value, and conclusion (write the conclusion out in words using no symbols.)  (Stat > Basic Statistics > 1-Proportion.  Click on summerized data and put in the appropriate information.  Click on Options and pick the appropriate alternative hypothesis.)
2. Determine if a majority of women wash their hands after using a public restroom. Report the hypotheses, P-value, and conclusion.