lecture 13 - biostatistics II

Question 1

What is the standard deviation of a population?

Answer 1

How far, on average, points are from the mean (µ)

Question 2

What is the term for the variability of sampling distribution/the standard deviation of sample means?

Answer 2

Standard error (SE)

Question 3

As sample size increases, what happens to the spread of the sampling distribution?

Answer 3

Spread gets narrower

Question 4

Where will 95% of sample means lie on a normal distribution curve?

Answer 4

Within 1.96 standard errors of the population mean

Question 5

What is continuous data in biostatistics and how is it summarised?

Answer 5

Data points can be anywhere between a theoretical maximum and minimum. Summarised with mean and spread/standard deviation

Question 6

What is categorical data in biostatistics and how is it summarised?

Answer 6

A measurement off discrete variables, when only a fixed number of values/possible outcomes are possible. Summarised with the number/percent/proportion in each category.

Question 7

What are we ‘95% confident of’ in terms of the population, in biostatistics?

Answer 7

For repeated sampling, 95% of confidence intervals will contain the true population mean or proportion.