Question 1

Which of the following best describes a parameter in statistics?

Accepted Answer

A numerical measure that describes a characteristic of a population

Question 2

A researcher collects the heights of all students in a university. The collection of all these heights is called:

Accepted Answer

A population

Question 3

Which of the following variables is categorical and nominal?

Accepted Answer

Race

Question 4

A variable that can take on any value within a given range is called:

Accepted Answer

Continuous

Question 5

Which of the following is NOT a measure of central tendency?

Accepted Answer

Variance

Question 6

Given the data set: 2, 4, 4, 6, 8, what is the mode?

Accepted Answer

4

Question 7

Which Excel function would you use to calculate the sample mean of a data set in cells A2:A100?

Accepted Answer

=average(A2:A100)

Question 8

If a data set is right-skewed, which of the following is true?

Accepted Answer

Median \u003c Mean

Question 9

The formula for the sample variance $$s^2 is$$:

Accepted Answer

$$s^2$$ = \frac{\sum (X_i - \overline{X}$$)^2$$}{n-1}$$

Question 10

A Z-score is calculated as:

Accepted Answer

$$Z = \frac{X - \overline{X}}{s}$$

Question 11

If the mean of a data set is 50 and the standard deviation is 10, what percentage of data falls between 30 and 70 according to the Empirical Rule?

Accepted Answer

68%

Question 12

Which of the following best describes the relationship shown by a correlation coefficient of $$r = -0.85$$?

Accepted Answer

A strong negative linear relationship

Question 13

A boxplot is useful for displaying which of the following?

Accepted Answer

The five-number summary and outliers

Question 14

Which of the following is NOT a characteristic of a normal distribution?

Accepted Answer

Mean is always zero

Question 15

A scatter plot of two variables shows points clustered in an upward trend from left to right. This suggests:

Accepted Answer

A positive correlation

Question 16

Which Excel function would you use to find the 75th percentile of a data set in cells B2:B100?

Accepted Answer

=quartile(B2:B100, 3)

Question 17

If a data set has a mean of 100 and a standard deviation of 15, what is the Z-score for a value of 130?

Accepted Answer

$$Z = \frac{130 - 100}{15} = 2.0$$

Question 18

Which of the following statements about variance is TRUE?

Accepted Answer

Variance is measured in squared units of the original data

Question 19

Which of the following is a disadvantage of using the range as a measure of variation?

Accepted Answer

It ignores the way in which data are distributed

Session 1: Defining, Organizing, and Visualizing Data in Business Statistics

스터디 가이드 - 연습 문제