Measurement, scales , numbers, rates, ratios and risk Flashcards
1
Q
whats the purpose of statistics
A
to infer about the population
2
Q
how to make inferences about the entire population
A
- take a sample and then generalise that the population
3
Q
samplulation population must be
A
representative
unbiased
precise
4
Q
types of errors that can occr in a study that maybe affect results
A
- chance (random) error
- due to samping variation
- reduced as sample size increases
- Bias (systematic error)
- bias is quantified by the difference between the true value and expected value
- increasing sample size doesnt eliminate it
5
Q
why does increase population decrease random error
A
increase in precision i.e can estimate the mean better (reduce uncertainty )
helps with targetting certain outcomes
6
Q
systematic error sources
A
- selection bias ; when sampling study smaple