Shapely Glasses Does the shape of a glass play a role in determining the amount of time it takes to finish the drink? Researchers identified 159 male and female self-professed social drinkers. One week the subjects were given a 12 ounce beer with either a straight glass or a curved glass. A week later the subjects were given a 12 ounce beer in the other glass. The first week, subjects were given a glass and asked to consume the drink at their own pace while watching television. The time to complete the drink was measured. During the second week, the subjects were given the other shaped glass and asked to complete a computer task. Again, the time to complete the drink was measured. The type of glass given in the first week was determined randomly. The researchers found that the time to complete the drink was significantly faster for the curved glass.


What is the response variable? Is it qualitative or quantitative?

Verified step by step guidance

1. Identify the response variable by determining what outcome the researchers are measuring. In this problem, the researchers are interested in the "time to complete the drink."
2. Recognize that the response variable is the amount of time it takes for each subject to finish their drink, which is a measurable quantity.
3. Since time is measured on a numerical scale (e.g., seconds or minutes), the response variable is quantitative, not qualitative.
4. Summarize that the response variable is the "time to complete the drink," and it is quantitative because it represents a numerical measurement.
5. Note that understanding the type of response variable helps in choosing the appropriate statistical methods for analysis.

Key Concepts

Response Variable

The response variable is the main outcome measured in an experiment or study. It reflects the effect of the explanatory variable and is what researchers observe or record to assess changes. In this question, the response variable is the time it takes to finish the drink.

Quantitative vs. Qualitative Variables

Variables can be quantitative (numerical) or qualitative (categorical). Quantitative variables represent measurable amounts or counts, while qualitative variables describe categories or groups. Since time to complete the drink is measured in units (e.g., seconds), it is a quantitative variable.

Experimental Design and Randomization

Randomization in experiments helps reduce bias by randomly assigning treatments to subjects. This ensures that differences in the response variable are likely due to the treatment rather than other factors. Here, the order of glass type was randomized to fairly compare drinking times.