What You Can Do With Numbers - LECT 4

Question 1

How can you minimise error in results?

Answer 1

Make repeated measurements and use statistics to estimate accuracy

Question 2

Define the terms ‘trueness’ and ‘precision’

Answer 2

TRUENESS - how close average of own scores is to the true value = validity

PRECISION - how closely repeated measurements agree = repeatability

Question 3

What is the SI system?

Answer 3

Measurement system built around 7 base units and larger numbers of derived units

Question 4

What units are defined in their own technical way?

Answer 4

Seconds

Kilograms

Kelvin

Question 5

What are the 4 categories data can be measured in?

Answer 5

1. Nominal
2. Ordinal
3. Interval
4. Ratio

Question 6

Define the term ‘nominal measurements’

Answer 6

Numbers used to distinguish between individuals

• eg. Numbers on a footy jersey

Question 7

Define the term ‘ordinal measurements’

Answer 7

Numbers ordered according to a criteria

• eg. A is ahead of B but we don’t know by how much = Olympic medals

Question 8

Define the term ‘interval measurements’

Answer 8

How far apart numbers are apart on an arbitrary scale

• eg. Degree Celsius thermometer = no natural zero point

Question 9

Define the term ‘ratio measurements’

Answer 9

Scale has a natural zero point

• degrees kelvin thermometer = has an absolute zero