Measures of central tendency and dispersion

Question 1

What are the Measures of central tendency?

Answer 1

Mode
Mean
Median

Question 2

What is the mode?

Answer 2

• Most frequently occurring number in the data set
• Could be more than 1 modal value

Question 3

What is the mean?

Answer 3

The average
* Add up all of the values in the data set
* Divide by the total number of values there are

Question 4

What is the median?

Answer 4

• Arrange the values from lowest to highest (or vice versa)
• Median is the middle value. If there are 2 middle values add them and divide by 2.

Question 5

What are measures of dispersion?

Answer 5

Range
Standard deviation

Question 6

What is the range?

Answer 6

• Shows the spread of the scores- the bigger the range the bigger the spread of the scores
• Subtract the lowest value from the highest value = range

Question 7

What is standard deviation?

Answer 7

• Shows the spread of the data from the mean
• The higher the value the more spread out the data is (greater variation)- this may show that some people e.g. performed particularly well or poorly and could be anomalies
• The lower the value, the less spread out it is, so it is more closely clustered around the mean ( there is less variability) i.e. they performed more similarly