Standard Errors

What creates uncertainty?

using a sample rather than the full population means estimates are influenced by randomness

What can standard errors be used to describe?

uncertainty

What does sampling error describe?

differences between the metric made based on the sample and the true value of the metric for the whole population

What type of distribution is shown?

normal distribution

How does sampling error arise?

due to process of random sampling

What can simulations (e.g. creating fake scenarios in R) be used for?

exploring properties of a population

What assumptions do simulations have to meet in order to be used?

population assumptions must equal simulation assumptions

What is the equation for standard error?

SE = sd(x) / square root of n

What does a small standard error value suggest?

lower influence of sampling error when estimating mean

How is a standard deviation estimated?

using collected and calculated data

What is the standard error if the standard deviation of 25 measurements equals 5?

• SE = sd/ square root n

• 5/ square root of 25

• =1

What measurements can a standard error be calculated for (3)?

• mean of sample

• variance of sample

• difference between mean of 2 samples