PSYC*1010 Chapter 3: Central Tendency

Question 1

What is central tendency?

Answer 1

A statistical measure to determine a single score that defines the centre of a distribution

Question 2

What is the goal of calculating a central tendency?

Answer 2

To find a single score that is most representative of the entire group

Question 3

Which statistical measure is useful for making comparisons between sets of scores?

Answer 3

Central tendency

Question 4

What are the three measures of central tendency

Answer 4

• Mean
• Median
• Mode

Question 5

What is the preferred measure of central tendency?

Answer 5

Mean

Question 6

How is mean calculated?

Answer 6

By computing the sum of scores and dividing it by the total number of scores

Question 7

T or F: Changing the value of any score will change the mean.

Answer 7

True

Question 8

When will adding or removing a score for the distribution NOT change the mean?

Answer 8

When the new or removed score is the same as the mean

Question 9

What will happen to the mean is a constant value is added, subtracted, multiplied or divided to/from/by every score in a distribution?

Answer 9

The mean will change in the same way

Question 10

What does μ represent?

Answer 10

The population mean

Question 11

What do M and X̅ represent?

Answer 11

The sample mean

Question 12

What two values are needed to calculate weighted mean?

Answer 12

• The overall sum of scores for the combined group
• The total number of scores in a combined group

Question 13

How is mean calculated from a frequency distribution table?

Answer 13

Multiply each score (X) by its frequency and divide the product by the total number of score (Σf)

Question 14

What is the median?

Answer 14

The midpoint of scores in a distribution when they are listed in numerical order

Question 15

How is the median calculated when the number of scores is even?

Answer 15

When the number of scores is even, the median is found by computing the average of the two centre scores

Question 16

Which measure of central tendency is best when extreme scores or skewed distributions are present?

Answer 16

Median

Question 17

Which measure of central tendency should be used if an undetermined score is present?

Answer 17

Median

Question 18

Which measure of central tendency should be used if there is an open-ended distribution/ no upper limit?

Answer 18

Median

Question 19

Which measure of central tendency should be used if scores are measured on an ordinal scale?

Answer 19

Median

Question 20

What is the mode?

Answer 20

The score or category with the greatest frequency

Question 21

Which measure of central tendency corresponds to an actual score in the data?

Answer 21

Mode

Question 22

What is a bimodal distribution?

Answer 22

A distribution with two modes

Question 23

What does a bimodal distribution indicate?

Answer 23

That two separate and distinct groups of individuals exist within the sample/population

Question 24

What is a multimodal distribution?

Answer 24

A distribution with more than two modes

Question 25

When is the term "major mode" used?

Answer 25

Used casually to refer to the taller peak of two modes that are unequal yet have distinctly high frequencies

Question 26

When is the term "minor mode" used?

Answer 26

Used casually to refer to the smaller peak of two modes that are unequal yet have distinctly high frequencies

Question 27

Which measure of central tendency should be used if scores are measured on a nominal scale?

Answer 27

Mode

Question 28

Which measure of central tendency is best when variables are discrete?

Answer 28

Mode

Question 29

T or F: Modes are rarely, if ever, shown in a graph.

Answer 29

True

Question 30

What is the main determining factor when deciding how means and medians will be presented?

Answer 30

The scale of measurement used for the independent variable

Question 31

Where are the mean, median, and mode located in a symmetrical distribution?

Answer 31

Exactly at the centre

Question 32

Where are the mean, median, and mode located in a rectangular distribution?

Answer 32

- Mean and median are exactly at the centre - There is no mode

Question 33

Where are the mean, median, and mode located in a positively skewed distribution?

Answer 33

In order from left to right: mode (at the peak), median, then mean

Question 34

Where are the mean, median, and mode located in a negatively skewed distribution?

Answer 34

The measures of central tendency are presented in order from left to right as mean, median, then mode (at the peak)