MID-TERM EXAM: PART 1 – SECOND TRY
The following data (made up, of course!) are from a sample of 10 college students and represent how many times they checked their cell phone in an hour when they were in class.
|# of times phone checked|
|Supplied by professor|
PART A: Complete the following calculations by hand. (Yes, you can use a calculator!). SHOW ALL OF YOUR WORK– each step you took to arrive at your answer.
(14 points total)
1. Compute the mean (2 points)
2. Compute the Sums of Squares (2 points)
3. Compute the SD (2 points) – Note please use N-1 in formula because this is
from a sample
4. Compute the SE of the mean (2 points)
5. Compute the 95% confidence interval around the mean. (2 points)
6. Compute the z-score for 13? (2 points)
7. Determine what height falls at the equivalent of a zscore of 1.5. (2 points)
PART B: Complete the following using SPSS. To turn in this work, you will need to save your output file as a Word file. (In SPSS, under File, click on Export.It will give you an option to save your file as a Word document. ) You can copy the questions below that require text right in the output file or keep this as a separate Word file. For the questions requiring screen shots, these can also be embedded in the output file or the separate Word file. (16 points)
1. Enter the data into an SPSS file. (SHOW YOUR DATA FILE – both data and variable view)
2. Compute a boxplot to determine if there is an outliers(s). If there is an outlier, identify which respondent(s) are the outliers. (2) SHOW RESULTS
3. If there is an outlier, describe EXACTLYhow you will correct for it and why you chose this method. (2)
4. Make any corrections needed to outliers in the data file following the method you chose in #3. Compute the remaining on the updated data file. (SHOW YOUR UPDATED DATA FILE – both data and variable view) (1)
5. Use SPSS to calculate the mean and SD. (If you found an outlier(s), compute the mean and SDon the data in which the outlier has been fixed.) (2) SHOW YOUR RESULTS.
6. Do you think it is necessary to examine whether your data are normally distributed or not? Please explain your answer. (2)
7. Use the appropriate statistical testto determine whether the data are normally distributed and explain whatthe results show and why. SHOW YOUR RESULTS. (2)
8. A researcher wanted to see if college students check their phone more often than professors during a class period. The average number of times a professor checked their phone was 3. State the null hypothesis and the alternates for such a study. (3)
9. Assume that the probability value of the statistical test obtained was p< .112. What should the researcher conclude about the significance of the results and what do the results mean in terms of what the researcher found. (2)
Please use the following data for the Midterm Part 1 – retake if you choose to retake the exam.