Exam 9: Numbers, Comparisons, and Calculations

Variables measured as real numbers have minimal effect on their plausible values.

The frequency or count of a categorical variable by its categories are whole numbers.

How is "relative risk" calculated?

An online feedback form, maintained by a courier service company, asks customers with complaints to mark a number from 1 to 10 after interacting with customer care, with 1 denoting very dissatisfied, and 10 denoting extremely satisfied. What is this feedback called?

Design a research study on a particular topic of your choice. You may use any studies you had designed in the previous chapters. In addition to the outcome variable, you should have at least three independent variables in the study. Discuss the measures and their definitional limits for each of the variables used in your study.

How is "prevalence" different from "incidence?"

During exploratory analysis of the variables in the study you designed in Question 1, what types of calculations would you conduct in order to compare values? Explain your choices of calculations.

The level of measurement of a variable determines the type of comparison and mathematical calculation that are possible for values of the variable.

Explain the difference between position in an ordered list and the measure of values in the list. Give an example to show this difference.

Give an example where the concept and units are different for the numerator and denominator of a ratio.

What kind of a distribution is given by a quintile?

Discuss the limits on values of an integer measure, and, whether the topic or context have an effect on plausible values of the measure. Illustrate with an example.

What can be determined when comparing two values of a nominal variable?

Why is a ratio not affected by the system of measurement?

Values of dimensions of rooms in an apartment are always denoted as whole numbers.

With the help of an example, explain the difference between a decile and a quartile distribution of values.

Why are limits on rank in a sorted list not affected by the topic or context of study?

What are the definitional limits of a decile and a quintile distribution of values? Illustrate with an example.

What are the upper and lower limits of a percentile distribution of values?

The risk of being affected by a particular virus was 1 in a 1,000 for people who had not been vaccinated against the virus. For those who had been vaccinated against the virus, the risk was 1 in 15,000. What is the relative risk of catching the virus?