Answer to Question 1
Hennigan, Del Rosario, Heath, Cook, Wharton, and Calder (1982) looked at larceny rates in cities before and after television became prevalent. There were two time periods during which television ownership jumped; cities acquired television stations during one of the two periods.. During the first period, those cities with high television ownership experienced a higher increase in larceny than other cities; when the second set of cities experienced prevalent television ownership, their crime rates increased.
This time-series design allowed a tentative conclusion about a causal link between television watching and increased crime because the crime rate was most affected when television became prevalent. Prior to and after the surge in television ownership, the two sets of cities were comparable in larceny rates; only the introduction of television was associated with an upsurge in the crime.
Answer to Question 2
a. without face-to-face interaction between participants and researchers, we don't know if the participant understands the directions and follows them
b. remote collection of data means that the researcher doesn't know about the quality of the data, that is, whether the participant took the process seriously
c. it isn't clear what population we can generalize our data to because we don't know the characteristics of the population from which participants come
d. the ethical guidelines associated with research may be harder to follow because participants may not understand the research (informed consent) or read about its purpose (debriefing); there is no opportunity for compensatory followup; participants who are not of legal age may participate
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