Statistical Studies, Methods of Sampling, and Statistical Questions

A researcher wants to determine the average time high school students spend on homework each night. Which method would be most appropriate?

• Experiment

• Sample survey

• Observational study

• Secondary data analysis

Which of the following best describes the purpose of randomization in a study?

• a. To increase the sample size
  

•  b. To ensure all participants are identical

•  c. To reduce bias and create comparable groups

•  d. To eliminate the need for a control group

In the context of statistical studies, what is primary data?

•  a. Data collected directly by the researcher for the specific study

•  b. Data that is considered more important than other data

•  c. Information gathered from published sources

•  d. The first set of data collected in a longitudinal study

What does a z-score of 0 indicate about a data point?

• It is one standard deviation above the mean

•  It is equal to the mean

•  It is one standard deviation below the mean

•  It is two standard deviations above the mean

What type of sampling is shown?

• Simple Random Sample

• Systematic Sample

• Cluster Sample

• Stratified Sample

A student wants to know which type of pizza the students at his high school prefer. Which option would give an unbiased, representative sample:

• Asking all the students in the hot lunch line.

• Asking 10 random students from each homeroom.

• Asking every other student who gets off a school bus.

• Asking all the 10th graders.

_______ is the entire group of objects or individuals considered for a survey.

• Sample

• Population

• Random Sample

• Quartile

Choosing a sample because it is convenient.

• Convenience Sampling

• Random Sampling

• Voluntary-Response Sampling

• Systematic Sampling

Fred wants to determine the mean hourly wage of the working students at his school. He asks thirty of his friends their hourly wage and calculates the sample mean to be $6.  Is this random or biased sampling?

• Random

• Biased

each item or person in the population is as likely to be chosen as any other

• biased sample

• systematic random sample

• unbiased sample

• simple random sample