Question

determine whether the study is an experiment or an observational study, and then identify a major problem with the study. in a survey conducted by usa today, 1485 internet users chose to respond to this question posted on the usa today electronic edition: is news online as satisfying as print and tv news? 52% of the respondents said yes. this is an observational study because the researchers apply a treatment to the individuals. what is a major problem with the study? a. the sample is not very large. b. this is a convenience sample with voluntary response, which has a high chance of leading to bias. c. the results apply only to internet users. d. there is no blinding or replication, which has a high chance of leading to bias.

Explanation:

Part 1: Determine if it's an experiment or observational study

An observational study is when researchers observe or measure variables without applying a treatment. In this survey, USA Today just collected responses from Internet users who chose to respond—they didn’t apply any treatment (like assigning a group to read a specific news type). So it’s an observational study because researchers did not apply a treatment to the individuals.

Part 2: Identify the major problem with the study

• Option A: The sample size (1485) is actually large, so this is incorrect.
• Option B: The survey uses a convenience sample (Internet users who visit USA Today’s electronic edition) with voluntary response (people choose to respond). Voluntary response samples are biased because those with strong opinions (or who have time/interest) are more likely to respond, distorting results. This matches the problem.
• Option C: While results apply to Internet users, the bigger issue is the sampling bias from voluntary response, not just the population scope.
• Option D: Blinding/replication is for experiments, not observational studies (this is an observational study, so blinding isn’t relevant here).

Answer:

• Type of study: Observational study (because researchers did not apply a treatment to the individuals).
• Major problem: B. This is a convenience sample with voluntary response, which has a high chance of leading to bias.