Logical Reasoning

PT7 · S1 · Q10 A large group of hyperactive children

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A large group of hyperactive children whose regular diets included food containing large amounts of additives was observed by researchers trained to assess the presence or absence of behavior problems.

Conclusion (it can be concluded that)

Food additives can contribute to behavior problems in hyperactive children.

Evidence

A large group of hyperactive children on high-additive diets was assessed, switched to a low-additive diet for several weeks, and assessed again.

Behavior problems fell from nearly 60 percent of the children to 30 percent.

Evaluate

Whenever we see a study / experiment and the author presents some data from the study, we're usually going to be getting an Explain Curious Fact argument with comparative evidence (60% vs. 30%) and a causal conclusion ("can contribute").

When we see Explain Curious Fact on Flaw, we're usually being tested on the author's failure to consider alternate explanations (i.e. the famous Causal flaw).

In this case, we're trying to figure out why behavior problems were cut in half, once the kids were on the low-additive diet for several weeks.

The author is claiming it's because the food additives were making their hyperactivity worse, and so now that they're eating less of those, their hyperactivity was lessened.

We want to consider Alternate Explanations for why they're behaving better: maybe something else in their lives changed over the several weeks / maybe some other component of the study is causing it.

And we want to assess the Plausibility of the author's story: - is there a control group that is still on the high-additive diet that is still at 60% behavioral problems?

- do the effects of additives on hyperactivity actually fade within the course of several weeks if a child stops eating additives?

- does a reduction in hyperactivity lead to a reduction in behavior problems?

Goal

Look for an answer suggesting an Alternate Explanation for the drop in behavioral problems or bringing up some idea we would need to examine in order to evaluate the plausibility of the story the author is telling.

10.

The evidence cited fails to establish the conclusion because

there is no evidence that
Bad Objection
Since this starts with presumes / takes for granted / fails to establish / provides no evidence that, we assess whether it was a Necessary Assumption. Did the author's argument need the reduction in additives to be proportionate to the reduction in behavior problems? No, it doesn't have to be a mathematically perfect relationship to be a true causal relationship. If additives were reduced by 75%, but that led to a 50% reduction in behavioral problems, that would still show a causal relationship. A disproportionate effect would still be an effect.
10% picked this
Correct
there is no way to
Why this is right
This is complaining that we never heard about a Control Group. If they kept some of the kids on their same high additive diet and saw that 60% of them still showed behavioral problems three weeks later, then that would be strong evidence that lowering additives for the other group was the causal difference-maker that led to behavioral improvement. Meanwhile, if the kids in the control group also dropped to only 30% problematic, then we wouldn't think that low additives did anything special (since the kids who never changed their additive intake were experiencing the same drop in behavior problems). Because every child in the study changed diets, nothing shows what would have happened to similar children who did not. The drop from 60 to 30 percent might have occurred anyway, through maturation, familiarity with the observers, or other changes over those weeks. Without that comparison, the evidence cannot establish that the diet, rather than something else, produced the improvement.
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
76% picked this
exactly how many children exhibited
No Impact
Percentages are enough to show the size of the change. Knowing the exact head count would not make the comparison any more or less valid. The passage does say the group was large, so we're not worried that this is taking 60% / 30% of suspiciously small actual numbers. Flaw answers that demand specific figures / names / definitions are almost always wrong.
3% picked this
there is no evidence that
Bad Objection
Since this starts with presumes / takes for granted / fails to establish / provides no evidence that, we assess whether it was a Necessary Assumption. Did the author's argument need to assume that the behavior of some of the kids NOT affected by additives? No. If we negated that idea and said, "Hey author, EVERY kid's behavior was affected by additives" that wouldn't weaken. We'd basically be proving his conclusion.
3% picked this
the evidence is consistent with
Bad Objection
It is true that some kids may have gotten worse, but overall the group would have gotten much better (going from 60% to 30%). The fact that there would be some counterexamples where additives are apparently helping some kids behave better, it would still be the case that for the most part having additives in the diet was making things worse, so the author's weak conclusion that "additives can contribute to behavior problems" would still be safe.
7% picked this

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