Measures of Central Tendency and Dispersion Flashcards
1
Q
what are the measures of central tendency?
A
- mean
- median
- mode
2
Q
what is the mean?
A
allows us to recognise the average
3
Q
what are the strengths of the mean?
A
- most sensitive of the measures of central tendency(includes all values)
- more representative of the data as a whole
4
Q
what are the weaknesses of the mean?
A
- mean is easily distorted by extreme values
5
Q
what is the median?
A
middle value in a data set when scores are arranged from highest to lowest
6
Q
what are strengths of the median?
A
- extreme scores don’t affect it
- easy to calculate
7
Q
what are weaknesses of the median?
A
- it is less sensitive than the mean
8
Q
what is the mode?
A
- most frequently occurring score/value
- two modes = bi-modal
9
Q
what are strengths of the mode?
A
- easy to calculate
10
Q
what are weakness of the mode?
A
- not a very useful piece of information
11
Q
what are the measures of dipersion?
A
- range
- standard deviation
12
Q
what is the range?
A
highest value - lowest value +1
13
Q
why do you add 1 when calculating the range?
A
mathematical correction, raw score may have been rounded up or down
14
Q
what are the strengths of ranges?
A
- easy to calculate
15
Q
what are the weaknesses of the range?
A
- only takes into extreme values
- unrepresentative of the data set as a whole
