Computer Assignment for Quiz 5


Look at Problem 2.139 on page 103; the data are on p. 104. Pretend these 37 are a random sample of U.S. prisoners who committed suicide while in jail. (They are not a random sample, but such pretense is quite common.) The two variables of interest are Days in Jail before suicide and Murder/Manslaughter charge. Enter the Murder/Manslaughter data as 1=Yes, 0=no. Use Minitab to do the following. Bring all your printouts to the quiz. It is okay to paste them into a single document if you wish. You may be asked to hand in all or a portion of of your output as part of the quiz. You also might be asked questions about your output. Do not write anything on your printouts before the quiz, except possibly your name and student number.
  1. Make a dot plot of Days in Jail.
  2. Make a stem-and leaf display of Days in Jail.
  3. A precentage histogram of Murder/Manslaughter
  4. Generate basic descriptive statistics (mean, median, standard deviation, Q3 etc.) for Days in Jail.
    1. Using this output, a calculator and tables, calculate a 99% confidence interval for µ.
    2. A criminologist claims that the average prisoner who commits suicide will do so withing the first 30 days. Using the descriptive statistics again, test this at alpha = 0.05. Answer all the standard questions.
    3. Using the standard nomal table, obtain the p-value.
  5. Generate basic descriptive statistics for the Murder/Manslaughter variable.
    1. Using this output, a calculator and tables, calculate a 95% confidence interval for p. Yes, you can do it.
    2. A criminologist claims that half the prisoners who commit suicide is in for murder or manslaughter. Using the descriptive statistics again, test this at alpha = 0.05. Answer all the standard questions.
    3. Using the standard nomal table, obtain the p-value.
  6. Obtain the confidence intervals and tests and p-values above directly from Minitab, without using tables or calculator. This is a good way to check your work, if nothing else. Note you are being asked for four items here.
  7. Do example 7.2 on p. 301 using Minitab.
  8. Do example 7.4 on P. 310 using Minitab. You are using "Summarized data," so tick that radio button.
  9. Do example 8.5 on p. 349 using Minitab. Of course you are assuming normaility. The book should have mentioned this.

Important notice: You must do the computer work yourself. It is an academic offense to present someone else's work as your own, or to allow your own work to be so presented. If you bring a copy of someone else's printout to the quiz and we catch you, we will prosecute both parties under the academic code of offenses.