Medium LSAT Evaluate the Argument Questions Practice Questions

Concept Explanation

LSAT Evaluate the Argument questions require you to identify the specific piece of information that would most effectively determine the validity of a given conclusion. These questions occupy a middle ground between Strengthen and Weaken questions, as the correct answer choice functions like a "pivot" that could either bolster or break the argument depending on how it is answered. To succeed with Medium LSAT Evaluate the Argument Questions, you must isolate the conclusion and identify the central assumption or logical gap connecting the premises to that conclusion.

A highly effective technique for these questions is the Variance Test. Since the answer choices are often phrased as questions or "whether" statements, you can test an option by providing two extreme, opposite answers to it. For example, if an answer choice asks, "Whether the new law will be enforced?", you test "Yes, it will be fully enforced" and "No, it will not be enforced at all." If the "Yes" makes the argument much stronger and the "No" makes it much weaker, you have found the correct answer. This process is essential for navigating LSAT Prep materials efficiently.

Common logical flaws addressed in these questions include causal errors, sampling bias, and overlooked alternatives. Unlike GRE Argument tasks which often require broad critiques, LSAT evaluation is laser-focused on the specific relationship between the evidence provided and the claim made.

Solved Examples

1. Argument: The city council claims that installing new streetlights will reduce crime because areas with high lighting levels historically have lower burglary rates. Therefore, the council should proceed with the installation to ensure resident safety.
   Question: Which of the following would be most useful to know in evaluating the argument?
   Solution:
   1. Identify the conclusion: Installing streetlights will reduce crime.
   2. Identify the premise: High lighting correlates with low burglary.
   3. Identify the gap: Correlation does not equal causation. Perhaps low-crime areas just happen to have more lights because they are wealthier.
   4. Correct Answer: Whether the low crime rates in well-lit areas were established before or after the lights were installed. If before, the lights didn't cause the reduction (weakens); if after, they likely did (strengthens).
2. Argument: A study showed that 80% of people who use "Glow-Skin" cream reported fewer wrinkles after one month. Thus, Glow-Skin is an effective treatment for reducing wrinkles.
   Question: Which of the following is most important to determine to evaluate the argument?
   Solution:
   1. Conclusion: Glow-Skin is effective.
   2. Premise: 80% of users reported improvement.
   3. The Gap: We don't know what would happen without the cream (the control group).
   4. Correct Answer: What percentage of people who did not use any cream also reported fewer wrinkles during the same period? If 80% of non-users also improved, the cream is useless.
3. Argument: Company X's profits increased by 20% this year. The CEO attributes this to the new employee wellness program. Therefore, the program was a financial success.
   Question: Which of the following would be most helpful in evaluating the CEO’s claim?
   Solution:
   1. Conclusion: The wellness program caused the profit increase.
   2. Premise: Profits rose 20% after the program started.
   3. The Gap: Other factors could have caused the rise.
   4. Correct Answer: Whether the industry as a whole experienced a similar 20% increase in profits this year. If the whole industry rose, Company X's growth might just be a market trend, not the program's doing.

Practice Questions

1. A local bookstore owner noticed that sales of mystery novels increased significantly whenever the temperature dropped below 40 degrees Fahrenheit. The owner concluded that cold weather causes people to want to read mysteries. To evaluate this, it would be most helpful to know:

2. Recent data shows that students who participate in organized sports have higher GPAs than those who do not. The school board argues that increasing funding for sports will therefore improve the academic performance of the student body. Which of the following is most important to determine?

3. A tech company recently switched to a four-day work week and saw a 10% increase in total monthly output. The management claims the shorter week boosted productivity. To evaluate this claim, it is most useful to know:

4. An environmentalist argues that the decline in the local bee population is due to the use of Pesticide X. As evidence, the environmentalist points out that bee populations began to drop the same year Pesticide X was introduced. Which of the following would be most useful to know?

5. A nutritionist claims that drinking green tea helps with weight loss because a group of volunteers who drank three cups a day lost an average of five pounds over two months. To evaluate this, one should ask:

6. The mayor of City Y claims that the new bike lanes have made commuting safer, citing a 15% decrease in reported bicycle accidents since the lanes were installed. What would be most useful to determine in evaluating the mayor's claim?

7. A marketing firm suggests that their new ad campaign for Brand Z soda was successful because sales rose by 5% in the month following the campaign's launch. Which of the following is most important to evaluate?

8. Scientists found that people who sleep more than eight hours a night have a lower risk of heart disease. They concluded that extra sleep protects the heart. To evaluate this, it is most useful to know:

9. A university decided to offer free tutoring to all freshmen to increase retention rates. After one year, retention rose by 12%. The Dean concluded the tutoring was the cause. Which of the following is most helpful to know?

10. A financial analyst predicts that Stock A will rise because the company just hired a world-renowned CEO. To evaluate this prediction, it is most useful to know:

Answers & Explanations

1. Answer: Whether the bookstore ran a major promotion on mystery novels during the cold months. Explanation: If a promotion occurred, the sales spike might be due to the discount rather than the weather. If no promotion occurred, the weather hypothesis is stronger.
2. Answer: Whether students with higher GPAs are more likely to self-select into organized sports. Explanation: This addresses the direction of causality. If high achievers choose sports, then sports aren't necessarily the cause of the high GPA.
3. Answer: Whether the company hired additional staff at the same time the four-day week was implemented. Explanation: If staff numbers increased, that could explain the higher total output regardless of the work schedule.
4. Answer: Whether other factors, such as a new parasite or habitat loss, also occurred in the year Pesticide X was introduced. Explanation: This identifies potential confounding variables that could be the actual cause of the bee decline.
5. Answer: Did the volunteers make any other lifestyle changes, such as starting an exercise program, during the study? Explanation: This tests whether the weight loss can be uniquely attributed to the tea.
6. Answer: Whether the total number of people commuting by bicycle decreased significantly after the lanes were installed. Explanation: If fewer people are riding, fewer accidents are expected even if the lanes aren't actually safer.
7. Answer: Whether sales of all soda brands in the region rose by a similar amount during that month. Explanation: This helps determine if the 5% rise was due to the specific campaign or a general market trend.
8. Answer: Whether people who have heart disease often suffer from insomnia or other conditions that reduce sleep. Explanation: This checks for "reverse causation"—perhaps heart health determines sleep, rather than sleep determining heart health.
9. Answer: Whether the university also implemented stricter admission standards the same year. Explanation: Stricter standards could lead to a more capable student body that is naturally more likely to stay, regardless of tutoring.
10. Answer: Whether the company’s stock has historically risen or fallen when previous "renowned" CEOs were hired. Explanation: This provides a baseline to see if the market actually reacts positively to such hires in this specific company's context.

Frequently Asked Questions

What is the difference between a Strengthen question and an Evaluate question?

A Strengthen question asks for a fact that makes the conclusion more likely to be true. An Evaluate question asks for a piece of information that could either strengthen or weaken the conclusion depending on the answer.

How do I use the Variance Test on the LSAT?

Take an answer choice and apply two extreme "answers" to it, such as "all" vs "none" or "yes" vs "no." If one extreme makes the argument much stronger and the other makes it much weaker, that is the correct choice.

Are Evaluate the Argument questions common on the LSAT?

They appear less frequently than Flaw or Strengthen questions, usually appearing 1-2 times per Logical Reasoning section. However, they are high-value because they test your ability to see the "hinge" of an entire argument.

Should I look for the flaw first in these questions?

Yes, identifying the logical gap or assumption is the best first step. The correct answer will almost always target that specific gap by asking a question that "plugs" or "exposes" it.

Can an Evaluate question have an answer that is not a question?

Yes, answers are often phrased as "Whether..." statements or "The degree to which..." phrases. These function identically to questions and can still be tested using the Variance Test method.