RC Question 17 Explanation
DISCUSSION: This question tests your understanding of the scientific method, a common LSAT theme.
In a proper experiment, you should keep all the variables the same, except for the variable you’re testing.
So the dummies should be the same, except for the breast stripe.
___________
- This would strengthen the experiment, by showing that the behavior is common to all titmice, and not just those from a particular flock.
- CORRECT. If this is true, then the titmice might have been reacting to some other difference, and not the change in stripe size.
- The size of the breast stripe didn’t correlate with age (lines 43-45), so the age of the birds shouldn’t matter.
- As long as the food was something that the titmice wanted to eat (and was always the same), then this wouldn’t matter. The birds could likely see the breast stripe before they saw what food was in the tray.
- This somewhat supports the hypothesis. The idea was that symbols such as stripes would determine status and avoid the need for fights.
Or perhaps once an aggressive bird got close enough, it would realize the experimental bird was a dummy.
I got down to B and C pretty quickly, and because 43-45 equally controls for age AND physical characteristics, I picked on the basis that age was a specifically cited as a covariate in the Harris Sparrows case. They controlled for a slew of physical factors (body weight, sex, wing length). Are we meant to read “physical characteristics” as meaning only physical characteristics besides those which they controlled for? If this was the case why did they not instead say a specific, not listed physical characteristic like talon size or something?
The experiment just showed that birds were confident or afraid based on the size of the breast stripe. The only change in the experiment was in the stripe. ALL birds had the same reaction.
Paragraph 3 said stripe width was the only factor correlated with fighting ability. Age wasn’t. The fact that a factor is mentioned doesn’t mean it is a decisive factor that must be included in any test.
Whereas B just devastates the experiment. In an experiment you’re only supposed to change one factor. B shows several are changed.
Hope that helps!
I reread the specific passage in question several times over – I understand that a point being made is that controlling for other factors does not mean that they have no effect. The size of a bird dummy, if varied, will possibly influence the results. But doesn’t this mean that a change in the quality of the subjects, like their age, couldn’t equally devastate the study.
If all the birds included in the study were all abnormally heavy and had longer wings, they may react differently to the dummys. Likewise, just because age is controlled for, that doesn’t mean it has no influence. Controls simply mean the influence is accounted for. Age cannot be ruled out as having no effect on social standing merely because it is controlled for in determining that the stripe has some effect, just as the effect of the size of the birds cannot be ruled out of having any influence merely because they are controlled for.
C would demonstrate that the study has failed to adequately control for a variable that the earlier study did control for. We cannot rule out that the same phenomenen observed in the Harris sparrows may be occurring here.
An experiment doesn’t need to have perfectly representative samples to be useful. For example, if you show a comedy movie to adults and they laugh, that shows the movie can be funny. It doesn’t decisively prove that the movie is funny for all audiences in all places of all ages but it does provide evidence for the movie’s humour.
If there were no juveniles, the study could still show status signaling in the adults birds which were part of the study.
But if B is true the study is just useless. We don’t know if differences between the dummies were due to stripe width vs. another factor.
In other words, the experiment is testing: “Do birds react to differences in stripe width?”. Showing the dummies to adults can help answer that question. But if the dummies are fatally flawed then you can’t answer the question even if you show the dummies to every titmouse in the world including juveniles.
Hope that helps! Sampling is subtle.