GMAT AWA Flawed Survey and Sample Reasoning Quiz

The survey was conducted at a single large state university, which limits the diversity of the student population represented. College students at this institution may have different preferences compared to those at smaller colleges or universities, leading to results that do not accurately reflect the opinions of all college students.

Excluding employees who quit within the past year introduces selection bias, as their dissatisfaction is not represented in the survey results. This skews the data, leading to an overestimation of overall employee satisfaction, since the most dissatisfied individuals are removed from the sample.

The survey's results reflect self-selection bias because it only included existing subscribers, who are likely to have a preference for the magazine. This method excludes the opinions of non-subscribers, leading to a skewed representation of the overall American population's preferences.

The argument assumes a direct causation between the ad campaign and the sales increase without considering other factors that could have contributed, such as seasonal trends, competitor actions, or changes in consumer behavior. This oversight weakens the conclusion by failing to acknowledge alternative explanations for the observed sales growth.

The flawed assumption lies in generalizing the exercise habits of gym members to the entire American population. Gym members are likely to be more fitness-oriented than the average person, making it inappropriate to conclude that most Americans exercise regularly based solely on this specific group.

This argument assumes that because Company A's stock price increased after hiring a new CEO, the new CEO's leadership directly caused the increase. This reasoning overlooks other potential factors influencing the stock price, such as market conditions or company performance, leading to a logical fallacy of confusing correlation with causation.

The survey was conducted in an Apple store, which likely attracted a biased group of participants who already favor iPhones. This non-random selection method skews the results, as it does not accurately represent the broader population of smartphone users, leading to an overestimation of iPhone preference.

The argument relies on a survey that excludes employees on leave, which may lead to a biased representation of employee opinions. By not including this group, the survey results may not accurately reflect the views of the entire workforce, undermining the claim that "most employees" support the new policy.

The researcher focuses solely on college graduates earning over $100,000, neglecting individuals who achieved similar financial success without a college degree. This selective consideration leads to survivor bias, as it fails to account for a broader population, thus skewing the conclusion about the necessity of college for financial success.

The argument incorrectly assumes that the increase in coffee sales directly causes health improvements. This is a classic case of confusing correlation with causation, as other factors could contribute to the sales rise without implying a health benefit from coffee consumption. Correlation does not establish a cause-and-effect relationship.

The survey focused solely on students in honors classes, which may not accurately reflect the views of the entire high school population. This creates a sampling bias, as the opinions of students in regular or lower-level classes could differ significantly, leading to an overestimation of college attendance plans.

The argument relies on a limited survey of users who self-selected to participate, which may not represent the broader population. This leads to a hasty generalization about the vitamin brand's effectiveness. Additionally, the self-selection bias suggests that only satisfied users chose to respond, skewing the results and overstating the brand's superiority.