stats test 1 vocab

undercoverage bias

some people cannot be chosen thus not represented well

nonresponse bias

some people cannot be reached or refuse to answer thus not represented well

response bias

responses are not truthful or accurate thus not represented well

voluntary response

people decide themselves wether or not to join the study

nonresponse

failure to reply

population

the complete group of people that the research wants to draw conclusions about

sample

a smaller group made up of people from the larger group being represented

observational study

researchers collect and analyze data, they do not impose solutions or treatments. no effects are being tested

experiment

researchers collect and analyze data while imposing solutions or treatments to test the effects. effects are being tested

confounding variables

outside factor in the study that has an effect on the data in the study. something that cannot be controlled and is not being measured yet has an effect. this can lead to false evidence

explanatory variable

factor that you manipulate, control, or observe to predict the changes

response variable

the results in a study. you cannot directly control or manipulate this, it comes from what you control and manipulate

four steps of the statistical investigative process

1. forming a question

2. collecting data

3. analyzing data

4. interpreting results

sampling variability

natural difference in results when you take multiple random samples from a population

convenience sample

when you only collect data from people that are easy to reach, you don’t go out of your way to get a random sample, just what’s easy for you

random sample

everyone in a large group has an equal chance to be picked for a study