Q13 - Government statistics show

[kijijifoursale]

I was between (C) and (D) on this question, and had trouble ruling out (C).

The argument concludes by saying: Andersen family's real incomes must have increased over the last five years

Why? Andersen family's income is average for families; average income for families has risen over the last five years.

Is (C) wrong because even if most families' incomes are below average, the conclusion could still be true that A's family incomes increased?.

Initially, I thought this was a contender since if most families incomes are below average, then Andersen's family doesn't necessarily have to increase, since a small portion of extremely wealthy families could account for the rise in average income.

For example, say there are 100 families included in the statistics. 90 of them made <$10,000/year, which no change over the past 5 years. 10 of them made $1,000,000, and over the past 5 years their income went from $1M, to $10M. Then, this group of 10 would account for the rise in income, which means that if Andersen's family falls in the group of 90, it doesn't have to be true that their income also increased.

[smithcarston]

Same question as above, why is (D) correct?

[jwms]

(C) is wrong because the issue is the Andersens, and not the 'possibility' of most families' income being below average. Sure, that's a possibility, but the egregious flaw committed in this argument is (D): just because the Andersens are average in income for families this year doesn't mean they were 5 years ago.

(C) is a red herring: it's potentially a flaw, but attacks the overall context of the argument and not the specific argument made about the Andersens. Key in on what the argument core is here; that's what this question is testing.

[maryadkins]

(C) is wrong because the issue is the Andersens, and not the 'possibility' of most families' income being below average. Sure, that's a possibility, but the egregious flaw committed in this argument is (D): just because the Andersens are average in income for families this year doesn't mean they were 5 years ago.

(C) is a red herring: it's potentially a flaw, but attacks the overall context of the argument and not the specific argument made about the Andersens. Key in on what the argument core is here; that's what this question is testing.

Great explanation jwms. Yes!

Let's identify the flaw here. So we have this average family income that has gone up over the last five years. Picture a graph with a rising line that represents "family income." It's at a high this year! Woohoo!

The Andersens are on that dot!

So, the argument concludes, their income must have gone up over the last few years, too!

But wait: just because they HAPPEN to be smack on the "average family income" dot THIS year doesn't mean their income has been smack on the dot every year for the past five! Maybe last year they were WAY above average, and then mom or dad Andersen lost his/her job, and now they're way down from where they used to be.

This is what (D) says.

As for the others that have not been addressed:

(A) is not happening in the argument.

(B) is not true. The argument accounts for inflation.

(C) isn't actually true. The argument is about the Andersens, not most family.

(E) is a premise debooster and we don't attack premises.

Hope this helps!

[danwilyms]

I'm still not ready to let go of (B).

There are three references to "income" in the argument:

"real (adjusted for inflation) average income for families"

"Anderson family's income"

"[Anderson] family's real income"

It's the middle one that is throwing me, for it requires the assumption that the argument is referring to real income. Both the other two references were careful to specify "real," while the middle one, without that adjective, could be referring to income not adjusted for inflation.

On other questions the absence of adjectival modifiers matters immensely. Why not here?

[AyakiK696]

I had totally the same line of thought as the above poster. What threw me off was that the argument went from talking about REAL average income to AVERAGE income, and then concluded about the family's REAL average income. Were we just supposed to assume that the argument was talking about the real average income for the second premise as well? Shouldn't the answer be B...?

[ohthatpatrick]

When you are describing the present day's income and present day's average family income, there is no need to adjust for inflation.

You're just talking about a current slice of time. Inflation affects the whole economy, so the present is what it is.

Say that America underwent massive inflation and avg income of $60,000 suddenly became an avg income of $200,000 by 2020.

If the Anderson family makes $200k in 2020, then their income is average for families. There's no need to adjust that for inflation.

It's only when you compare time periods that you need to adjust for inflation, because you're looking at two numbers, and the comparison can be distorted by not factoring in inflation.

For example, if the Andersen family's income was avg in 2017 and avg in 2020, then it would look like
in 2017 - they made $60k
in 2020 - they made $200k

Wow! Is their family doing way better than before? Not necessarily. We need to adjust for inflation, and when we do, we realize that in real terms, their family is doing just the same as before.

tl;dr
Since the 2nd fact is comparing Anderson family income NOW to average family income NOW, it doesn't need to be adjusted for inflation.

The 1st and 3rd facts are comparing avg income NOW to avg income 5 YEARS AGO,
or comparing Andersen's income NOW to Andersen's income 5 YEARS AGO.

[LukeM22]

I have a quick question: for Flaw questions where the answer prompts are "fails to consider XYZ" or "overlooks the possibility of XYZ"; would it be recommended, similar to the Negation test for necessary assumption questions, if we were to simply "grant" XYZ and find that it kills the argument, to just run with the answer? I notice that in the context of this question, if we were to simply add D to the stimulus, it just flat out kills the argument. I find this much less mentally taxing then thinking of every possible alternative explanation.

[ohthatpatrick]

There are three different types of Flaw answer choices, and they each kinda deserve their own mindset.

A correct answer will either
1. Identify a Necessary Assumption
2. Identify a Potential Objection
3. Describe the Author's Move (two-part answers)

IDENTIFY A NECESSARY ASSUMPTION
takes for granted
presumes, w/o providing justification,
assumes without warrant
fails to establish
neglects to specify

IDENTIFY A POTENTIAL OBJECTION
fails to consider
ignores the possibility
neglects the possibility

DESCRIBE THE MOVE (two-part answers)
concludes _____ on the basis of _____
infers, from the claim that _____ , that ______
confuses ____ with ____
mistakes ____ for _____
takes for granted that _____ because _____
and all the famous flaw answers, and any other description that doesn't fall into the above list

When I'm reading a #1 answer, I'm asking myself, "IS this a Necessary Assumption? Is this possibly too extreme? If I negated this, would it hurt the author's argument?"

When I'm reading a #2 answer, I'm asking myself, "if this were true, WOULD this Weaken? It this possibly out of scope?"

When I'm reading a #3 answer, I'm asking myself, "DOES this match the argument core? (if applicable: can I match the "conclude/infer part" to the conclusion and match the "on the grounds of / on the basis of / from the claim that" to the evidence?)"


(Note: there are like two or three examples I've seen (ever) for which there is an incorrect answer that used a #2 wording and WOULD, if true, have weakened. Those ended up being incorrect answers, though, because the weaken idea was something that hurt the conclusion but had little to nothing to do with the premise / with the reasoning, while the correct answer was more sharply directed at the author's reasoning mistake.)

[AshH953]

Thank you for all the explanations above!! I'm just so confused by this question and AC A.

As I read the stimulus I somehow came to this impression:

Premise: the stats say the average income is rising.
Additional premise: Anderson's family earns an average income.
Conclusion: Anderson's family income must have been rising as well.

The biggest flaw I caught here is, wait, avg income is rising, but it doesn't necessarily mean *every* family earning an avg income has its income rising! I thought it was tossing between different aspects of 'average', with the former one referring to a statistical idea, and the latter one narrows down to a single family.

I learn from other discussion that LSAT rarely has this 'double meaning' as the correct AC, but I really wish to know what is wrong with this one.