Test 3

Question 1

Mean

Answer 1

Average, sum of all values.

+ takes all values into account
- outliers can skew

Question 2

Median

Answer 2

Middle value when all values are ordered.

+ not affected by outliers
- does not consider all values

Question 3

Mode

Answer 3

Value that appears most frequently.

+ categorical data
- not descriptive, only tells you where most of the data points fell and nothing else

Multiple modes = bimodal

Question 4

Dispersion

Answer 4

How spread out the data is.

Measures: range & SD

Question 5

Range

Answer 5

Difference between the largest and smallest value.

+ quick and easy
- does not consider all values
- affected by outliers

Question 6

SD

Answer 6

Calculates the average distance from the mean value.

+ more precise
+ takes all values into account
- harder to calculate

Low deviation is better as it shows consistency.
Only used if data is ”approximately normal”, (bell curve on graph).

Question 7

Variance

Answer 7

How different the scores are from each other.
+ treats all (directions of) deviations the same
- artificially high

Question 8

Nominal data

Answer 8

Categories
Eg; gender, colour

Question 9

Ordinal data

Answer 9

Meaningful order + category

Eg; level of happiness, grades

Question 10

Interval data

Answer 10

Recognised scales

Eg; centimeteres, distance travelled

Question 11

Interval data

Answer 11

Recognised scales

Eg; centimeteres, distance travelled