Making inferences from samples

Front

What is a sample in statistics?

Back

A sample is a subset of individuals or objects selected from a larger population used to make inferences about the population.

Front

What is a population in statistics?

Back

The population is the entire group of individuals or objects that is the subject of a statistical study.

Front

What does it mean to make an inference from a sample?

Back

Making an inference from a sample means drawing conclusions about a population based on the data collected from a sample.

Front

If 125 out of 500 voters support a new dog park, how do you calculate the expected number of supporters in a town of 35,000 voters?

Back

Use the proportion: (125/500) * 35,000 = 8,750 expected supporters.

Front

What is the formula to estimate the number of broken bulbs in a shipment based on a sample?

Back

(Number of broken bulbs in sample / Sample size) * Total population size.

Front

In a sample of 50 light bulbs, if 2 are broken, how many broken bulbs would you expect in a shipment of 12,000?

Back

Expected broken bulbs = (2/50) * 12,000 = 480 broken bulbs.

Front

What is the sample size in a survey of 70 students?

Back

The sample size is 70.

Front

What is the significance of a random sample?

Back

A random sample ensures that every individual has an equal chance of being selected, reducing bias in the results.

Front

If 7 out of 40 students attend afterschool programs, how do you estimate the number of students attending in a school of 200?

Back

Use the proportion: (7/40) * 200 = 35 students expected to attend.

Front

What is the difference between a sample and a population?

Back

A sample is a smaller group selected from a population, which is the entire group being studied.