Lesson 15 - Descriptive Statistics

Question 1

Measures of Central Tendency

Answer 1

Inform us about central values for data
Ways of calculating typical value for set of data
Average can be calculated in different ways
Mean, Median, Mode

Question 2

Measures of Central Tendency

Mean

Answer 2

Calculated by adding all scores and dividing by amount of scores
Representative of all data
Most sensitive measure of central tendency
However, can be distorted by a single extreme value and mean may not be one of the actual scores in the set

Question 3

Measures of Central Tendency

Median

Answer 3

Calculated by arranging scores in order then choosing numerical midpoint
Unaffected by extreme scores
Outlier/Extreme values would not form part of the average measurement
Less sensitive than mean
Not representative of all findings

Question 4

Measures of Central Tendency

Mode

Answer 4

Most frequent value in a set
Unaffected by extreme scores
Does not say anything about other scores in the set

Question 5

Measures of Dispersion

Answer 5

How spread the data items are

Range, Standard Deviation

Question 6

Measures of Dispersion

Range

Answer 6

Calculated by taking lowest score from highest
Quick and easy to calculate
Easily distorted by extreme values

Question 7

Measures of Dispersion

Standard Deviation

Answer 7

Average amount that each score differs from mean
Takes into account all scores
More difficult to calculate than range