Measures Of Spread

Question 1

What is the range of data

Answer 1

How far the data spreads

Question 2

How do you find the range of data

Answer 2

Find the difference between the highest and the lowest values

Question 3

What is q1 called

Answer 3

The lower quartile

Question 4

What is q2 called

Answer 4

The median

Question 5

What is q3 called

Answer 5

The upper quartile

Question 6

What percentage is q1

Answer 6

25%

Question 7

What percentage is q2

Answer 7

50%

Question 8

What percentage is q3

Answer 8

75%

Question 9

Calculation for q1

Answer 9

(N+1)/4

Question 10

What is the calculation for q2

Answer 10

2(n+1)/4

Question 11

What is the calculation for q3

Answer 11

3(n+1)/4

Question 12

What do you do with the values worked out in the quartile equations

Answer 12

Find that value on the list of the numbers

Question 13

What do percentiles p1 to p99 do

Answer 13

Divide the data into 100 equal groups

Question 14

Formula to work out percentiles

Answer 14

P1 Position number =(n+1)/ 100. P2 position number= 2(n+1)/100. Etc

Question 15

What should you do if your percentile doesn’t fall on a whole number

Answer 15

Take the 2 numbers it lies between and find there mean

Question 16

What is the interquartile range

Answer 16

The difference between the upper and lower quartile

Question 17

Icr formula

Answer 17

Q3- Q1

Question 18

How to find the Inter percentile range

Answer 18

Find the difference between the 2 percentiles

Question 19

What do deciles divide the data into

Answer 19

Ten equal groups

Question 20

How to find deciles

Answer 20

D9 = 9(n+1)/10

Question 21

What is the Inter decile range

Answer 21

The difference between the first 9 deciles
D9 -D1

Question 22

What does having a large interquartile/percentile/decile range mean

Answer 22

That the data is spread out in their region
It’s more varied and less consistent

Question 23

What does having a small interquartile/percentile/decile range mean

Answer 23

That the data is more consistent and less varied

Question 24

What does the interquartile range tell you

Answer 24

The range of the middle 50% of the data where most activity is going on and is unaffected by outliers

Question 25

What is a disadvantage of the icr

Answer 25

Omits 50% of the data

Question 26

Advantages of using small percentile ranges

Answer 26

Let’s you see what is going on in smaller areas

Question 27

Why does the Inter decile range give a more realist idea to the spread of data than the range or interquartile range

Answer 27

It give the middle 80% and ignores any outliers