Homework #1

(due: section 501 - Wednesday, 7/29; section 502 - Thursday 7/30)

Attempt all questions.
  1. A manufacturer of workstations claims that a new workstation achieves a score of 200 on the Tower of Hanoi benchmark. An independent testing organization disputes this claim and believes that the workstation is slower than claimed.
    Note: The Tower of Hanoi benchmark score is the number of moves made in 25 microseconds.

    1. You have been hired by the testing organization to conduct an experiment to evaluate this claim. State the appropriate NULL and ALTERNATIVE hypotheses.
    2. You determine that a sample of 144 workstations is sufficient. You randomly select a sample of this size and discover that the mean benchmark score is 198 with a standard deviation of 4. Conduct a test of hypotheses and comment on the manufacturers claim.

  2. Experts claim that the average cost per line of code to fix the Y2K problem is $1.70 for the financial industry.

    1. You have been recently hired as a project manager at a large bank and have been asked by the CIO to conduct an experiment to test if the banks cost is different from the industry average. State the appropriate NULL and ALTERNATIVE hypotheses.
    2. You select a sample of 25 programs that have already been fixed and examine project management records for each program. You determine the cost per line of code for each program. Write a SAS program to provide the necessary p-values to test your hypotheses.
    3. Comment on:
      • the normality assumption.
      • the significance of the appropriate p-value for testing the hypotheses stated for part 1 above.

  3. A human factors engineer believes that a new graphical user interface will lead to more errors for a standard task suite than the vendors claim. The vendor claims 42 errors on average for the standard task suite. She conducts an experiment to measure the error rate for the new interface and computes the necessary statistics.

    Conduct a thorough analysis of her data using the procedure outlined in chapter 2 (Knafl notes). View the SAS output produced and complete the analysis.