Looks like no one added any tags here yet for you.
survey
researchers ask participants questions about the parameter of interest
observation
researchers observe the behavior of the participants/subjects without trying to influence it in any way
experiment
researchers assign a control and treatment group and manipulate the variables to determine if a relationship between variables exist
law of large numbers
as the sample size gets larger, the average gets closer to the โtrue/expectedโ value
correlation
two variables are statistically related, meaning they tend to change together
causation
one variable directly causes a change in another variable
simple random sample
a completely random method, every member of a population has an equal chance of being selected
example of simple random sample
a random number generator is used to select from the entire population
systematic random sample
members of the population are put in order and a starting point is selected at random. after that, every nth member of the population is selected
example of systematic random sample
selecting every 8th customer in a grocery store line.ย
stratified random sample
members of the population are grouped and then a certain number of members of each group are random selected
example of stratified random sample
surveying a representative number of students from each year of high school to understand overall opinions.ย
cluster random sample
members of the population are grouped and then the groups are randomly selected. each member of the selected group participates
example of cluster random sample
choosing a few random city blocks to survey residents about local services
volunteer sample
anyone in the population can join the sample
example of volunteer sample
asking people to complete a survey on a website about their favorite movies.ย
convenience sample
anyone who happens to be available is selected
example of convenience sample
asking colleagues at work about their lunch preferences.ย