1. An insecticide company exposes 10,000 cockroaches to its newest product, and exposes another 10,000 to their previous formula. When the test is completed, the researchers determine the mean elapsed time before a cockroach was killed by each product.
I. What is the population?
II. What is the sample?
III. Is the study observational or experimental? Justify your answer.
IV. If observational, identify ALL variables. If experimental, identify ALL independent and dependent variables.
V. For each of the variables identified in part IV, list which of the four levels/scales of measurement was used to obtain data on these variables?
VI. Classify each of the variables identified in part IV as either attribute or numerical.
2. Classify the following variable as nominal, ordinal, discrete, or continuous and state why it is such a variable:
religious affiliation.
3. Classify the following as an example of a nominal, ordinal, interval, or ratio level of measurement, and state why it represents this level: rankings of the top ten best-selling authors.
4. Construct a frequency distribution table to organize the following set of data:
109 114 111 109 109 106 110 114 114 112
111 110 114 114 110 113 114 105 107 107.
5. Construct a grouped frequency distribution for the following 28 scores using a class width of 4:
84 82 87 74 77 72 85 72 80 82 66 69 67 65
80 75 70 69 67 78 65 88 72 84 65 75 79 71.
6. Provide a different example for each of the following types of variables from your work or home life:
A) A continuous variable
B) An ordinal level of measurement.