Algebra 2 Sampling, Surveys and Experiments Quiz: 10 Questions with Explanations

A A convenience sampleB A random sampleC A voluntary sampleD A biased sample

Equal chances are the definition of a random sample.

A A surveyB An observational studyC A voluntary online pollD A randomized experiment

Only random assignment of treatments balances other variables so that cause and effect can be inferred.

A SurveyB Observational studyC ExperimentD None of them

The experiment is the one that assigns treatments, which allows conclusions about cause.

A 5%B 2%C 20%D 0.5%

1/sqrt(400) = 1/20 = 0.05.

A Increasing the population sizeB Surveying only volunteersC Increasing the sample sizeD Using a convenience sample

The margin of error shrinks as the sample size increases.

A 0.50B 0.35C 0.65D 1.00

The tallest bars are at 0.45 and 0.50, around the true value 0.5.

A It is too largeB People choose themselves, so the sample is not representativeC It is randomD It has a control group

Voluntary response samples overrepresent people with strong opinions.

A Receives the new treatmentB Receives no treatment or a placeboC Chooses its own treatmentD Is not measured

The control group provides a baseline for comparison.

A The data are biasedB The sample is too smallC The treatment had no effectD The difference is unlikely to be due to chance

A result that rarely occurs by chance alone suggests a real effect.

A Confounding variables may explain the patternB It uses random samplesC It always has a small sampleD It uses a control group

Without random assignment, other differences between the groups may cause the result.