MET 04 - Central tendency and dispersion

Question 1

What is the mean?

Answer 1

The arithmetic average calculated by adding up all the values in a set of data and dividing by the number of values

Question 2

What is the median?

Answer 2

The central value in a set of data when values are arranged from lowest to highest

Question 3

What is the mode?

Answer 3

The most frequently occurring value in a set of data

Question 4

What are descriptive characteristics?

Answer 4

The use of graphs, tables and summary statistics to identify trends and analyse sets of data

Question 5

What is standard deviation?

Answer 5

• A sophisticated measure of dispersion in a set of scores
• It tells us by how much, on average, each score deviates from the mean

Question 6

What is are measures of central tendency?

Answer 6

• The general term for any measure of the average value in a set of data
• Examples of measures of central tendency include the mean, median and mode

Question 7

What are the strengths of using the mean?

Answer 7

It is sensitive to all data as it includes all scores/values in the data set within the calculation meaning it is more representative of the data as a whole

Question 8

What are the limitations of using the mean?

Answer 8

• It is easily distorted by extreme values
• If skewed by outliers it is a misleading indicator

Question 9

What are the strengths of using the median?

Answer 9

• It is immune to effect of outliers/extreme values and easy to calculate

Question 10

What are the limitations of using the median?

Answer 10

It is less sensitive and does not use all data

Question 11

What are the strengths of using the mode?

Answer 11

Only way to give a ‘typical’ category with qualitative data

Question 12

What are the limitations of using the mode?

Answer 12

• It may not show centre of quantitative data
• It is a very crude measure

Question 13

What are the strengths of using the range?

Answer 13

• It is quick and easy to calculate
• Allows researchers to draw conclusions about their research at a faster pace
• It means that researchers can spend more time interpreting and drawing inferences from the data as opposed to calculating and analysing

Question 14

What are the limitations of using the range?

Answer 14

• The range is vulnerable to extreme scores
• This gives a misleading impression of the real dispersion of scores
• So, the range is not always a representative description of the spread of a set of data

Question 15

What are the strengths of using standard deviation?

Answer 15

It is a much more precise measure of dispersion than the range as it includes all values within the final calculation

Question 16

What are the limitations of using standard deviation?

Answer 16

• It can be distorted by a single extreme value
• Extreme values may not be revealed, unlike with the range