TABLE 11-11
a Student Team in a Business Statistics

question 15

True/False

TABLE 11-11
A student team in a business statistics course designed an experiment to investigate whether the brand of bubblegum used affected the size of bubbles they could blow. To reduce the person-to-person variability, the students decided to use a randomized block design using themselves as blocks. Four brands of bubblegum were tested. A student chewed two pieces of a brand of gum and then blew a bubble, attempting to make it as big as possible. Another student measured the diameter of the bubble at its biggest point. The following table gives the diameters of the bubbles (in inches) for the 16 observations.
$$\begin{array}{l}\text { Brand of Bubblegum }\\\begin{array} { l c c c c } \hline \text { Student } & \text { A } & \text { B } & \text { C } & \text { D } \\\hline \text { Kyle } & 8.75 & 9.50 & 8.50 & 11.50 \\\text { Sarah } & 9.50 & 4.00 & 8.50 & 11.00 \\\text { Leigh } & 9.25 & 5.50 & 7.50 & 7.50 \\\text { Isaac } & 9.50 & 8.50 & 7.50 & 7.50 \\\hline\end{array}\end{array}$$
-Referring to Table 11-11, the randomized block F test is valid only if the population of diameters is normally distributed for the 4 brands.

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Definitions:

Variance

A measure of the spread of a set of numbers, indicating how much the individual numbers differ from the mean.

Regression Analysis

A set of statistical processes for estimating the relationships among variables, focusing primarily on the dependence of a response variable on one or more explanatory variables.

Residuals

The differences between observed and predicted values in a statistical model, representing the unexplained part by the model.

Concerts Attended

Refers to the number of live music performances a person has gone to within a specified period.