Measures Of Central Tendency And Dispersion

Question 1

What are the 3 levels of measurements

Answer 1

Nominal, ordinal and interval

Question 2

What is nominal data

Answer 2

Data which is in separate categories

Question 3

What is ordinal

Answer 3

Data that is ordered in some way but difference between each is not the same

Question 4

What is interval data

Answer 4

When the data is measured using units of equal intervals

Question 5

What are the 3 measures of central tendency

Answer 5

Mean, median and mode

Question 6

What is mean

Answer 6

The average where you add up all the numbers and divide by the amount of numbers

Question 7

What is the median and how do you work it out

Answer 7

The middle number and you arrange the numbers in order and then work your way down to the middle

Question 8

What do you do if there are 2 middle numbers for your median

Answer 8

Find their average by adding them up and divide by 2

Question 9

What is the mode

Answer 9

Th most common data item

Question 10

When do you use mean

Answer 10

When the data is interval data

Question 11

When do you use median

Answer 11

When there is interval or ordinal data

Question 12

When do you use mode

Answer 12

When there is nominal, ordinal or interval data

Question 13

What is a strength of mean

Answer 13

It is the most sensitive measure of central tendency because it takes account of the exact distance between all of the values of all the data

Question 14

What is a limitation of the mean

Answer 14

Due to sensitivity the value can be distorted by extreme values therefore becoming unrepresentative

Question 15

What is the strength of median

Answer 15

Not affected by extreme scores, can be easier to calculate than the mean and can be used for ordinal data

Question 16

What is the limitation of using the median

Answer 16

Not as sensitive, the exact values are not reflected, just the middle numbers

Question 17

What is a strength of mode

Answer 17

Unaffected by extreme values and is the measure which can be used for nominal data.

Question 18

What is a limitation of mode

Answer 18

It is not useful for explaining data when there is more than one mode (common choice)

Question 19

What are the 2 types of measures of dispersion

Answer 19

Range and standard deviation

Question 20

What does ‘measures of dispersion mean’

Answer 20

This refers to how dispersed or spread out data items are

Question 21

What is the range

Answer 21

Highest value-lowest value

Question 22

When would you use range

Answer 22

It can be useful for data which is both finding the same mean but has different ranges, it can further describe the data

Question 23

What is a strength of using range

Answer 23

It is easy to calculate

Question 24

what are the limitations of using range

Answer 24

.It’s affected by extreme values
.fails to take into account the distribution of values

Question 25

What is standard deviation

Answer 25

It measures the spread of scores around the mean

Question 26

What does a higher standard deviations suggest

Answer 26

That the scores/results are more spread out and that there is a larger variation in the results

Question 27

What a re the strengths of standard deviation

Answer 27

.all values are used so it is more representative than the range
.its a more precise measure because it takes into account all the exact values

Question 28

What is a limitation of standard deviation

Answer 28

It may hide some of the characteristics of the data set such as extreme values