Question

You are planning on analyzing data that show the incidence of terrorist events across the United States. Write a brief paragraph that includes the following information:
i.) provide examples of different variables at the nominal, ordinal, and ratio scale variable that you would encounter in this context,
ii.) explain what type of central tendency (mean, median, or mode) you would use to best represent each of the three variables in your example, and
iii.) describe for which variable(s) you would be able to compute and interpret a standard deviation.

NOTE: Be sure to provide enough detail in your descriptions so that we can determine how each of your three variables are measured.

Answer 1

1) i) Nominal: Locations of terrorist attacks
Ordinal: Chronological order of attacks (1st attack, 2nd attack)
Ratio: Number of casualties
ii) Nominal and ordinal variables cannot be represented by measures of central tendency since the intervals between them do not have any mathematical value.

The ratio variable can be represented by either of the three, but I would consider mean to be the best since it would tell you how deadly, on average, the terrorist attacks were.
iii) It is only possible to calculate an SD for the ratio variable of the number of casualties per attack. This is because there would be a numerical value for each attack, which could be averaged, and the distance from each data point could be taken.