Question 1

Which of the following best describes a 'parameter' in statistics?

Accepted Answer

A measurement that describes a population.

Question 2

Given the data set $$\{4, 7, -3, 16\}$$, what is the sample mean $$\overline{X}$$?

Accepted Answer

$$\overline{X} = \dfrac{4+7+(-3)+16}{4} = 6$$

Question 3

Which of the following variables recorded from parked cars is most likely to have the largest standard deviation?

Accepted Answer

Horsepower

Question 4

A variable that tracks the color of a car is best described as:

Accepted Answer

Qualitative (categorical)

Question 5

Which formula correctly represents the sample variance $$S^2$$ for a data set?

Accepted Answer

$$S^2$$ = \dfrac{\sum (x - \overline{X}$$)^2$$}{n - 1}$$

Question 6

If the mean, median, and mode of a distribution are all equal, which type of distribution is most likely represented?

Accepted Answer

Symmetric distribution

Question 7

Which of the following is a correct interpretation of the 83rd percentile ($$P_{83}) in a $$data set?

Accepted Answer

83% of the data values are less than or equal to the value.

Question 8

Which of the following best describes a discrete quantitative variable?

Accepted Answer

A variable whose possible values are distinct individual numbers with space between them.

Question 9

Given the data set $$\{6, 5, 7, 9, 15, 30\}$$, what is the sample variance $$S^2$$?

Accepted Answer

$$S^2 = 62$

Question 10

Which of the following statements about standard deviation is correct?

Accepted Answer

Standard deviation is measured in the same units as the mean.

Question 11

A sample of 20 UT students is selected from all UT students. In statistical terms, this sample is:

Accepted Answer

A sample

Question 12

Which of the following is NOT a property of a uniform distribution?

Accepted Answer

Mean is less than median.

Question 13

In a right-skewed distribution, which of the following is true?

Accepted Answer

Mean \u003e Median \u003e Mode

Question 14

Which of the following best describes the sample space?

Accepted Answer

The set of all possible values of a statistical variable.

Question 15

If 25% of the data values are less than or equal to 96, and 75% are greater than or equal to 96, what is 96 in terms of quartiles?

Accepted Answer

The 1st quartile ($$Q_1)$$

Question 16

Which of the following is the correct formula for sample standard deviation $$S$$?

Accepted Answer

$$S = \sqrt{\dfrac{\sum (x - \overline{X})^2$}{n - 1}}$$

Question 17

Which of the following is an example of a continuous quantitative variable?

Accepted Answer

Miles per gallon of a car

Question 18

If a data set has a mean of 6, a variance of 62, and a standard deviation of $$\sqrt{62}$$, what are the units of the standard deviation?

Accepted Answer

Same as the original data

Question 19

Which of the following best describes a proportion?

Accepted Answer

The relative size of one part compared to the size of the whole, expressed as a ratio.

Question 20

Which of the following is true about the median in a symmetric distribution?

Accepted Answer

It is equal to the mean and the mode.

Foundations of Descriptive Statistics: Variables, Data, and Distributions

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