Measurement, scales , numbers, rates, ratios and risk

Question 1

whats the purpose of statistics

Answer 1

to infer about the population

Question 2

how to make inferences about the entire population

Answer 2

• take a sample and then generalise that the population

Question 3

samplulation population must be

Answer 3

representative

unbiased

precise

Question 4

types of errors that can occr in a study that maybe affect results

Answer 4

• 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

Question 5

why does increase population decrease random error

Answer 5

increase in precision i.e can estimate the mean better (reduce uncertainty )

helps with targetting certain outcomes

Question 6

systematic error sources

Answer 6

• selection bias ; when sampling study smaple