Problem:
In the article "Measuring the gender gap on the internet," Bruce Bimber evaluated the difference in the rates of internet usage between men and women in the US. His hypothesis as that there is no difference in internet usage and sex. Using a telephone survey, he randomly selected 1000 people every year for in 2015, 2016, 2017, 2018, and 2019. The author found that while a gap exists it decreased over time. Moreover, the author found that although women are less likely to be high frequency users, the gap is not due to gender itself; that is, there is no significant difference between men and women. Rather the difference is due to situational factors that are more common for women than men. For example, two groups of low use include homemakers who are outside the labor force and lower income persons who tend to be women. Besides gender, why did the author include other variables in the study? A) To eliminate alternative explanations. B)To control for maturation and attrition. C) To create control groups for comparison purposes. D) To capture spurious relationships.