Parametric and Nonparametric
Label each of the following situations "P" if it is an example of parametric data or "NP" if it is an example of nonparametric data.
1. A manufacturer produces a batch of memory chips (RAM) and measures the mean-time-between-failures (MTBF). The manufacturer then changes a manufacturing process and produces another batch and again measures the MTBF. Did the change to the process improve the MTBF? ____
2. From a written survey where the respondents were asked to rate an individual on a scale of 1 to 5, one group rated an individual a 3.7, another group rated the individual a 4.3. Is the difference statistically significant? ____
3. A catering company is buying equipment in order to set up their own store. They have a choice of two ovens that they can purchase for the store. The used oven is $100 less than the new oven, but its heating calibration is off by 20 degrees. Which one is a better buy for them? ____
4. Jim Smith owns three real estate offices in Anytown. He has decided to open one more office, but he cannot decide between Hometown or Uptown as the town where he wants to locate. He will be comparing the mean number of homes sold per real estate agent, and the mean commission percentage earned by agents in the two towns to make his decision. ____
5. A study to determine if job absenteeism is distributed evenly over the week. ____
6. Mel's Diner has been surveying their customers for the past couple of years about their dining experience in the restaurant. The survey uses a scale of one to five, five being best to indicate customer satisfaction. Mel's customer satisfaction averaged 2.5 last year, but this year it is 2.9. Is this difference statistically significant? ____
7. Sally's Beauty Salon just opened for business. Sally assigns the stylists customers on a rotation basis so that everyone is kept busy all day. One month after she opened the salon, Sally's customer count for each stylist was (a) 20 customers; (b) 30 customers; (c) 15 customers; and (d) 25 customers. Has Sally been fair in how she allocates customers to each of the stylists? ____
8. A comparison of salaries between male and female employees in the same organization. ____© BrainMass Inc. brainmass.com December 24, 2021, 8:36 pm ad1c9bdddf
Parametric tests require that the data are measured on an interval or ratio scale, where we can talk meaningfully about the numerical interval between each score (and assume it's equal) or where we can talk about ratios between scores (eg. 20 is twice as long as 10). Non-parametric tests are used for data that do not meet these requirements. Looking at the questions above: ...
Provides 8 research questions and explains whether each would be addressed using parametric analyses or non-parametric analyses, and why.