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This discussion introduces you to normal probability via the calculated z-score

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This discussion introduces you to normal probability via the calculated z-score. A z-score converts a non-standard normal distribution into a standard normal distribution; a standard normal distribution has a mean of zero and standard deviation of one.

Additional z-score properties and details are provided later in the course. For this assignment, what is needed is the capability to calculate a z-score and find its associated probability (see Table A-2 in your textbook). Here is an example:

• Excel equation: z = (Your Score (X) – Mean)/(Standard Deviation) OR z = (X – Mean)/S.
• Z-score and probability calculation example:
  • Assume Intelligent Quotient (IQ) scores are normally distributed with a Mean of 100 and Standard Deviation of 15.
  • Assume a friend has an IQ score of 130 (X).
  • The z-score is then calculated: z = (130 – 100)/15 = 30/15 = 2.00.
  • Find Table A-2 in your textbook. The probability (green shaded area) associated with z = 2.00 is p = 0.9772.
  • The probability of another friend scoring “higher” (non-shaded area) than 130 is: p = (1.0000 – 0.9772) = 0.0228 or 2.28%.

Scenario

Day 2 of the airshow arrives, and the weather is worsening. The temperature is 50^oF, and strong thunderstorms are predicted. Continuing intermittent moderate to strong runway crosswinds (25 Knots sustained, with gusts to 40 Knots). Fortunately, all Day 2 flying sorties are accomplished with only minor incidents.

Your team collected these simulated data for Day 2 flying sorties:

Complete

In Microsoft Excel, complete the "Airshow – US Military Aircraft Performance" table by adding the calculated column and row values for mean, standard deviation, and z-score column values (use Sortie 10 data as the value of "X" in the z-score equation); report your calculated values to two decimal places (i.e., 0.12). For reporting probability, use Table A-2 in your textbook and report the value of p to four decimal places (i.e., 0.1234).

Save your work as a file to your computer and then read the Canvas instructions on How do I embed an image in a discussion reply as a student? (Links to an external site.)

Post & Discuss

Post the image of your spreadsheet into the discussion area along with a narrative of your findings before the fourth day of the module week to receive full credit. Return at least once later in the module week to provide meaningful comments to two or more of your classmates' posts. DO NOT “post and run” – making all three posts in the same visit. You need multiple visits to the discussion area to gain multiple perspectives by reading all of the posts and replies.

Review the Discussion Rubric for detailed grading information.