STAT EXAM 2 review solution
descriptive statistics - numerical and graphical summaries are used to characterize a data set or
describe a relationship between two variables (range mean)
inferential statistics - sample date is used to make conclusions about a broader range of individuals
than just those who were observed
fundamental rule for using data for inference - data can be used to make an inference about a much
larger group if the sample can be considered to be representative of the population in respect to the
question of interest
population - the entire group of units about which inferences will be made
sample - the group of units that are actually measured or surveyed
simple random sample - the list of units from which the sample is selected. every unit of the
population has the same chance of being selected
sampling frame - the list of units from which the sample is selected. problem occurs when its not the
same as the target population
census - when every unit of the population is measured or surveyed
bias - a survey is considered if the method used to get the value for the dataset consistently produces
values that are too high or too low
selection bias - when the method used for selecting participants for the survey does not produce a
sample that reflects the population being studied
