descriptive statistics

Question 1

what are measures of central tendency?

Answer 1

any measure which calculates an average value within a set of data

Question 2

list 3 measures of central tendency

Answer 2

mean mode median

Question 3

give strengths of the mean

Answer 3

makes use of all values
good for interval data

Question 4

how do you calculate the mean?

Answer 4

sum of all values / number of values

Question 5

give a limitation of the mean

Answer 5

influenced by outliers so unrepresentative

Question 6

how do you calculate the median?

Answer 6

arrange data from lowest to highest then find central value

Question 7

give strengths for the median

Answer 7

• not affected by extremes
• good for ordinal data

Question 8

give a limitation of the median

Answer 8

not as sensitive as mean, doesnt use all data

Question 9

how do you calculate the mode?

Answer 9

most frequently occuring value in a set of data

Question 10

list 2 measures of dispersion

Answer 10

range
standard deviation

Question 11

give a strength of the mode

Answer 11

useful in nominal data

Question 11

give a limitation of the mode

Answer 11

not useful whne theyre are several modes

Question 12

how do you calculate the range?

Answer 12

highest score - lowest

Question 13

give a strength of the range

Answer 13

easy to calculate

Question 14

give limitaitons of the range

Answer 14

• affected by extremes
• doesnt use all data

Question 15

how do you calculate standard deviation?

Answer 15

square root of variance
-low SD means more data is clustered close to the mean so less data spread

Question 16

give a strength of standard deviation

Answer 16

precise measure

Question 17

give limitaions of standard deviation

Answer 17

• difficult to calculate
• affected by extremes