Measurement

Question 1

What are the types of data?

Answer 1

Nominal
Ordinal
Interval/ratio

Question 2

What is nominal data?

Answer 2

Data that is labelled in categories, but is qualitative so there is no indication of the quantity in each category. Cannot be ordered.
Examples: gender, colour, favourites

Question 3

What is ordinal data?

Answer 3

Qualitative data in which variables exist in naturally-occurring categories. Can be easily ordered (e.g. ranking). For example a satisfaction survey (placed in categories and details how many responses were in each category).

Question 4

What is interval/ratio data?

Answer 4

Data that is quantitative and can be measured/ E.g. weight, height, age, size

Question 5

What are the two types of interval/ratio data?

Answer 5

Discrete (whole numbers) or continuous (fractional numbers)

Question 6

What is measurement error?

Answer 6

The difference between a measured value and the true value. There are two types: random and systematic

Question 7

What is a random error?

Answer 7

Random error is due to fluctuation in the condition during measurement. It doesn’t affect the average, but it affects the variability.

Question 8

What is a systematic error?

Answer 8

Occurs as result of a flawed experimental design or tool. It affects the average and therefore causes bias.