This is a great conceptual example of a part to whole flaw involving the probability of an event in multiple stages, but it has a math error and a language error I just have to nitpick! The chances of survival is NOT the odds. In a frequentist model, odds are the ratio of the times an event occurs over its complement (success over failure). The Probability (or if you want a more casual term, chance) of an event occuring is the ratio of the the event occurring over all trials. Ping is attempting to calculate a probability, but calling it odds. It's also the wrong probability. 8 trials with P success = 0.9 is 0.9 ^ 8 which is about 0.43, or 43 percent. We can find out how many trials it takes to get that probability down to 18.5%, with log base 0.9 of 0.185. That's 16 tries. Obviously you don't need the math for the LSAT, but I would suggest it be fixed in the text at least :) Switch odds to chance or probability, and switch 18.5% to 43% (or the number of stages from 8 to 16).
On one coin you guess Heads. Great. You are right! That was a 50% chance.
Second coin you have another 50% chance of getting it right.
BUT.
On the whole, to get all 4 coins guessed right, you have a 1/16 or 0.0625 chance of getting all 4 coins heads up, or all coins tails up.
That is the part-to-whole flaw. You have a higher probability of getting the parts right, flipping one coin, BUT you have a low probability that the WHOLE (4 coins heads up) right.
I like think of this question of every stage as a parlay.
You can have a 9 leg parlay with -250 odds on each leg. Individually, they are all likely to hit (based on the odds at least), and yet when combined altogether the odds are +1966 and NOT -250.
Similar to each stage as described by JY. Each stage is (like his example) 90/10 odds. This does not mean that the mission to mars has a 90/10 of no failure, as probabilities do not work that way.
K this is a unique misunderstanding im hoping someone could help me with
what i am confused about is that the arguer said that at ANY GIVEN stage, the odds are unlikely. This is still true, no? he basically said, pick a stage, any stage, your odds of survival are pretty good at that stage. this is fair to conclude. if odds of survival at every stage is 90%, then at any stage surval is 90%, no?
Now I get that he is trying to say that survivability is higher for the whole trip and that why its a parts whole. but to call that the flaw is innaccurate because all hes trying to prove is that the claim that odds of survival are really low is EXAGGERATED. so all he has to do is show that the odds are not as grave as the critic claims for it to follow.
we dont know what the critic considered in arriving at his conclusion so we cant really assess this argument. but if the new information about the backup systems at each stage was not considered by the critic then this argument is fine. the backup system improves survivability at each stage. now, this alone is not enough to say that the WHOLE trip will BE LIKELY TO SURVIVE. but the arguer ISNT proving that. he is just saying that its exagerated.
Even if there were 1000 stages and survivabiliity was at a fraction of a percent, if this new information in the argument shows that survivability is just a tiny bit higher, then hes successfully proving that the critics claim is exaggerated.
Remember, he NEVER said that disaster is unlikely for the whole trip, but just at any given stage. I think that is true.
@Charles_ I think what is confusing you is that the claim you have identified for the argument is that the claim is exaggerated. Rather, the claim is actually--from my understanding, so please correct me anyone if I am wrong--that "a fatal catastrophe is quite unlikely at any stage." The "exaggerates the risk" is a premise that supports his conclusion that the the backup system significantly decreases the chances of a fatal catastrophe. The first two sentences of the argument are the two premises, and the last sentence is the conclusion. By identifying the last sentence as the conclusion (and even by looking at the conclusion alone), we understand why the arguer thinks that the leading critic is wrong for saying that sending explorers with current technology is a bad idea. The conclusion itself also highlights the prime flaw is parts to a whole (by relying on the idea that every stage is backed up will mean that the entire journey as a whole is safe). I hope this helps!
uhh I got this right because I figured surviving each stage wasn't the whole picture. if each stage is 10 years and there are 20 stages, it doesn't matter that each individual stage is survivable, everyone will still probably die (of old age) on the journey. thats how I got to the answer without thinking about probabilities at all.
if there's someone who's good at probability, pls do explain how the probability is 18.5%? figured i would learn some probability too in between all this
@steamboatwillie Yeah so the 18.5% was a random number. How probability actually works is that if you have a 90% chance of survival 8 times, you multiply .9 by itself 8 times to find the actual chance of survival which is .43 or 43% chance (.9^8=.43).
This is how casinos make money. For example a roulette wheel has 36 numbers + 0 and 00. Betting on red, you would double your money if you are correct, but since 0 and 00 dont count, your odds of success are 18/38 or apx 47.3%. When you bet on red for 2 turns, your odds of success become .473^2 or just 22.43% when fair odds would be 25%.
ngl this one was easy for me, I always look at the question before he explains and I felt great cuz he used the same explaining (very rare occasion). The way I figured this out was they were concered with the flight (WHOLE) but then reassured us by saying every componet (PART) was safe. I found the AC that addressed this and was the first one, I always read all of them even if Im sure about one just cuz (sometimes its my worst misteak)
My first thought was that it would be because they said the technology isn't developed enough which would render the backup system arguement as untrue. Barked up the wrong tree.
Why are your odds of survival 18.5%? Aren't your odds 0.9^8? Which is 43.1%, not 18.5%. 0.9^16 is 18.5%, but I don't see why you would double the exponent.
Breaking out the math on this is way overcomplicating it. Just memorize a list of the most common informal fallacies, and you'll be good. This argument commits the fallacy of composition, the opposite of the fallacy of division.
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58 comments
B sounded so right 😩
I get why the right answer is right but I have a difficult time completely grasping why exactly E is wrong.
This is a great conceptual example of a part to whole flaw involving the probability of an event in multiple stages, but it has a math error and a language error I just have to nitpick! The chances of survival is NOT the odds. In a frequentist model, odds are the ratio of the times an event occurs over its complement (success over failure). The Probability (or if you want a more casual term, chance) of an event occuring is the ratio of the the event occurring over all trials. Ping is attempting to calculate a probability, but calling it odds. It's also the wrong probability. 8 trials with P success = 0.9 is 0.9 ^ 8 which is about 0.43, or 43 percent. We can find out how many trials it takes to get that probability down to 18.5%, with log base 0.9 of 0.185. That's 16 tries. Obviously you don't need the math for the LSAT, but I would suggest it be fixed in the text at least :) Switch odds to chance or probability, and switch 18.5% to 43% (or the number of stages from 8 to 16).
ugh why does this feel like math...I chose lawyer bcs I hate math ....
This flaw is basically a flaw of probability.
Say you have 4 coins.
On one coin you guess Heads. Great. You are right! That was a 50% chance.
Second coin you have another 50% chance of getting it right.
BUT.
On the whole, to get all 4 coins guessed right, you have a 1/16 or 0.0625 chance of getting all 4 coins heads up, or all coins tails up.
That is the part-to-whole flaw. You have a higher probability of getting the parts right, flipping one coin, BUT you have a low probability that the WHOLE (4 coins heads up) right.
Hope this helps someone:
Op said : no big tech, no game.
Arg said: You yappin. We got a lil tech to help. We game.
Flaw: lil tech =/= big tech
Part of system =/= entire current tech available
I like think of this question of every stage as a parlay.
You can have a 9 leg parlay with -250 odds on each leg. Individually, they are all likely to hit (based on the odds at least), and yet when combined altogether the odds are +1966 and NOT -250.
Similar to each stage as described by JY. Each stage is (like his example) 90/10 odds. This does not mean that the mission to mars has a 90/10 of no failure, as probabilities do not work that way.
Hope this helps someone else understand.
@LowOriginalConnection type of thing i put the last $3.27 in my account on. (that lowkey helped so much)
@LowOriginalConnection this so helpful ty
K this is a unique misunderstanding im hoping someone could help me with
what i am confused about is that the arguer said that at ANY GIVEN stage, the odds are unlikely. This is still true, no? he basically said, pick a stage, any stage, your odds of survival are pretty good at that stage. this is fair to conclude. if odds of survival at every stage is 90%, then at any stage surval is 90%, no?
Now I get that he is trying to say that survivability is higher for the whole trip and that why its a parts whole. but to call that the flaw is innaccurate because all hes trying to prove is that the claim that odds of survival are really low is EXAGGERATED. so all he has to do is show that the odds are not as grave as the critic claims for it to follow.
we dont know what the critic considered in arriving at his conclusion so we cant really assess this argument. but if the new information about the backup systems at each stage was not considered by the critic then this argument is fine. the backup system improves survivability at each stage. now, this alone is not enough to say that the WHOLE trip will BE LIKELY TO SURVIVE. but the arguer ISNT proving that. he is just saying that its exagerated.
Even if there were 1000 stages and survivabiliity was at a fraction of a percent, if this new information in the argument shows that survivability is just a tiny bit higher, then hes successfully proving that the critics claim is exaggerated.
Remember, he NEVER said that disaster is unlikely for the whole trip, but just at any given stage. I think that is true.
Help me out pls
@Charles_ I think what is confusing you is that the claim you have identified for the argument is that the claim is exaggerated. Rather, the claim is actually--from my understanding, so please correct me anyone if I am wrong--that "a fatal catastrophe is quite unlikely at any stage." The "exaggerates the risk" is a premise that supports his conclusion that the the backup system significantly decreases the chances of a fatal catastrophe. The first two sentences of the argument are the two premises, and the last sentence is the conclusion. By identifying the last sentence as the conclusion (and even by looking at the conclusion alone), we understand why the arguer thinks that the leading critic is wrong for saying that sending explorers with current technology is a bad idea. The conclusion itself also highlights the prime flaw is parts to a whole (by relying on the idea that every stage is backed up will mean that the entire journey as a whole is safe). I hope this helps!
uhh I got this right because I figured surviving each stage wasn't the whole picture. if each stage is 10 years and there are 20 stages, it doesn't matter that each individual stage is survivable, everyone will still probably die (of old age) on the journey. thats how I got to the answer without thinking about probabilities at all.
unrelated but also related -
if there's someone who's good at probability, pls do explain how the probability is 18.5%? figured i would learn some probability too in between all this
@steamboatwillie Yeah so the 18.5% was a random number. How probability actually works is that if you have a 90% chance of survival 8 times, you multiply .9 by itself 8 times to find the actual chance of survival which is .43 or 43% chance (.9^8=.43).
This is how casinos make money. For example a roulette wheel has 36 numbers + 0 and 00. Betting on red, you would double your money if you are correct, but since 0 and 00 dont count, your odds of success are 18/38 or apx 47.3%. When you bet on red for 2 turns, your odds of success become .473^2 or just 22.43% when fair odds would be 25%.
hey so this was evil
bruh
and here is the violent humbling thanks lsat writers
Got this right but am commenting so i can review this for future reference
ngl this one was easy for me, I always look at the question before he explains and I felt great cuz he used the same explaining (very rare occasion). The way I figured this out was they were concered with the flight (WHOLE) but then reassured us by saying every componet (PART) was safe. I found the AC that addressed this and was the first one, I always read all of them even if Im sure about one just cuz (sometimes its my worst misteak)
every given stage (whole) v. any given stage (part)
damn I did not have a fun time w this one
im gonna cry and make the lsat test makers watch
Don't give them what they want
My first thought was that it would be because they said the technology isn't developed enough which would render the backup system arguement as untrue. Barked up the wrong tree.
#help
Why are your odds of survival 18.5%? Aren't your odds 0.9^8? Which is 43.1%, not 18.5%. 0.9^16 is 18.5%, but I don't see why you would double the exponent.
bro lost the plot
I'm not a violent person. But I'd be lying if I said the feeling of punching my monitor did not cross my mind. ._.
But I think I know why I got it wrong. I overlooked the step of finding the conclusion. ;_;
rofl
Breaking out the math on this is way overcomplicating it. Just memorize a list of the most common informal fallacies, and you'll be good. This argument commits the fallacy of composition, the opposite of the fallacy of division.
Interesting. Where can I find such a list?
https://www.txst.edu/philosophy/resources/fallacy-definitions.html
here are a couple but there are honestly so many - as long as you can get used to knowing where they are/how to spot them you'll be good!
@nicolesteinberg133 This is so helpful - thank you! Happy studying :)
Wow, my math degree was actually useful for once!
I am torn between skipping these lvl 5s and spending immense amount of time to MAYBE get them.
You have assumed that you will be able to spot level 5’s as soon as you see them…
Roughly. Most level 5’s I had no idea though. Every one I’ve seen is only level 5 because of how attractive the wrong answer choices were.
You cant tell the difficulty of a problem by reading them?
honestly in this question. ACs B, C and D all say the same thing. and E is just wrong. so i should've gotten to A from POE