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His last 4 cmv all come across with this same bulkshit 
He gets his viewed disproven but decides to flail about grasping for straws and refusing to ultimately define the things he wants go debate
/u/Farbio708 (OP) has awarded 3 delta(s) in this post.
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You want to buy a tractor. It's 50000$. You're planning on getting it, but there's no urgency. You're at home and get a notification that the tractor is on sale for 49,951$. Do you drive 5 minutes up to the store to get it? Probably not.

I don't understand. If I have the option to spend $50000 or $49951, and the latter only requires a 5 minute drive, then of course I would take the latter.
Of course, in real life, the sale on the hat is unlikely to last long - either because the inventory will be bought, or the store isn't particularly keen on running a 98% off sale in perpetuity. Similarly, the tractor is likely to have larger sales in the future if they aren't all sold. Those factors would make a real life person more likely to go get the hat now and wait on the tractor, but this hypothetical isn't intended to take future pricing into account. It's purely a hypothetical that assumes you get a $49 discount if you drive 5 minutes. >

Okay, hypothetical 2 is probably what I should have led with:
so you go to the store to buy a tractor for 50k and suddenly its 10$ more. do you buy it?
now u go to store to buy a 50c gum and its suddenly 10$ more. do you buy it? >

I maybe buy the tractor, I don't buy the gum. However, this hypothetical is asking a different question than the hypothetical in the OP.
It's likely that somebody values gum more than 50 cents, but less than $10.50. It's unlikely that a person values a tractor more than $50000, but less than $50010.
The original hypothetical assumes that you are willing to purchase the items at their original prices, and lowering the price from there obviously doesn't make a rational consumer unwilling to purchase them at the new price. >

This is probably why the original example is also only $2k and not $20k. When these small increments don't make a dent, the value isnt perceived differently. You can probably swing several hundred dollars in either direction for a $50k tractor or car before someone changes their mind. But even at $2k, someone might jump at $10 off its something they were already going to buy anyway. >

The point of the original example is that it's irrational to not perceive the values differently. >

Right I understand that. But the point is also that humans aren't necessarily rational. 
My point was agree with yours about the original price point. I genuinely can't remember if the car I want is listed at $49,999 or $49,900 or even $49,499. They're all basically the same. They're all "about $50k". So another $49 one way or the other doesn't matter. I value the original price of that vehicle somewhere between $49k and $51k. 
But that swing doesn't hold true for gum.
I think another issue is in the frequency of purchase. Both a phone and TV are things you don't purchase that often, so sure, you should be looking at those $10 the same. But a hat vs a tractor? I will probably buy 10 hats (or if you're multiple husband, 50 hats) by the time I buy a second tractor. So you can't treat these the same in terms of perceived value. I can also pick from thousands of other hats if this one didn't work out, but my options for tractors are way more limited. >

I think I read the same textbook. The example wasn't about "running out to buy something on sale." It was about whether or not to go to the store across town instead of the one near you. 
If you're already planning to buy the item, and the only question is "is it worth the extra gas money to drive across town to save $10," then it really doesn't matter if the item is expensive or not. 
Your extra examples weren't relevant, because in both cases you're spending money you don't need to be spending. >

I put the exact situation in the first part of the post. yes.

Your extra examples weren't relevant, because in both cases you're spending money you don't need to be spending.

you will be spending the money eventually... >

My point is, these are entirely different situations. In the first examples, you've already decided to buy it today, and the only question is where to buy it.
In the second example, you haven't already decided to buy it today; so when you see the sale, you have to decide if it's worth changing your plans, making arrangements for the money, etc. >

okay then use the tractor-gum analogy i gave elsewhere: you go to buy tractor. its 10$ more than normal. do u buy? now go buy a 50c gum and same thing. do u buy? >

That's still not the same thing. Deciding whether to buy something on sale really doesn't have anything to do with cost-benefit analysis. The textbook example was about whether or not to spend resources driving in order to take advantage of the sale. 
Please have your professor explain this to you. This is only Chapter 1. >

or how about you explain why this distinction matters. >

If you have decided you will buy today, all that's left to do is find the best deal. Once all possible deals are on the table, you can cost/benefit analyse them to see where you buy.
If you want to buy something eventually, but not necessarily today, then looking at all offers available today doesn't provide all possible deals. You don't have the constraint of buying today, so there's the possibility of a better deal arriving tomorrow, or the desire of buying disappearing in the future. You don't have to make a choice among the currently available offers, so there's more to it than selecting the best from a list. >

But don’t you also have the possibility that the deals you have today won’t be available tomorrow/go higher? I often face this buying pressure when investing. I don’t need to buy today, but also don’t want to miss out on gains. Quite the pickle. >

That sort of stuff gets abstracted away in thought experiments like this. >


In both cases, you're saving 49$, but clearly one is more compelling than the other. I don't think this is irrational. I think it's an appropriate assessment of the change in value

You haven't actually provided evidence for that, or challenged the original example, you just repeated that this is what people would intuitively do.
Which is the point of the example. People are irrational. They would save $10 on the phone but not save the exact same amount on the TV.
They would save $49 on the hat, but they wouldn't bother to save the exact same amount on the tractor for the exact same effort, because they care more about the perceived feeling of value, than about the actual tangible amount. >

I think the problem is you're changing a lot more than you intend to in your example. In both cases, you add the caveat "you're planning on getting it but there's no urgency". But this really doesn't capture the actual differences between buying a hat and a tractor. You can't just swing by and get a tractor and stash in your closet until you need it. There's just no way getting around that the act of acquiring a tractor is a much bigger deal logistically than getting a hat. So you're weighing that cost against the $49 dollars of savings, which is why you get your result. This tradeoff isn't present in the economics textbook.
A better example would be if you get a $49 discount by preordering either the hat or the tractor, but the pre-order process requires spending an hour to fill out a survey. In this case, it makes no sense to fill out the survey for the hat but not the tractor. In both cases, it's the same trade of $49 for an hour of your time. This is a lot closer to the example in the economics book. >

i fully agree with what you're saying here. thats my position. basically the textbook example is very specifically restrictive and isolated in its setup, whereas i can easily find examples where the abstracted principle doesnt make sense outside this restricted set of conditions. >


basically the textbook example is very specifically restrictive and isolated in its setup

That's because the textbook was trying to teach you a concept. Physics examples are usually also specifically restrictive and isolated (no air resistance, no friction, spinning of the earth doesn't matter, gravitational pull of the moon doesn't matter, etc.)
Easier to learn the concept being taught when you're not being distracted by several other things that factor into the calculation.
You're saying the equivalent of "Obviously gravity doesn't accelerate all things equally, I could drop a feather and a bowling ball and the ball would drop first. The textbook examples of two cannonballs of different weights or the feather and hammer on the moon are just specifically restrictive and isolated in its setup." >

yes >


You're saying the equivalent of "Obviously gravity doesn't accelerate all things equally, I could drop a feather and a bowling ball and the ball would drop first. 

Okay but you understand that this is wrong, right? >

explain >

Oh hi, just saw this.
Gravity does accelerate all things equally. It's an example of a counterintuitive principle of physics that people "feel" is wrong.  People feel that heavy objects should fall faster because gravity will "pull" them more, because they weigh more, but that's not true.
That's what Galileo was doing up the leaning tower (or so the story goes anyway); dropping off different objects to see if they hit the ground at the same time, regardless of mass.  The more intuitive (and older) theory was that a heavier object falls faster; this theory is wrong.
Of course, there are other forces, besides gravity, that can act on an object.  Air resistance being one of them. For most objects, it's negligible. A tomato, an iPhone, a canon ball and, idk, a car, dropped from 10ft, will hit the ground at pretty much exactly the same time for instance.  A feather, or a piece of paper, are different, not because gravity affects them any differently, but because they have a lot of air resistance, enough to actually meaningfully slow them down; that's why they float around the way they do on the way down.
Intuitively, most people feel that heavier things fall faster. If you ask a kid "if I put a really heavy weight in this ball, and drop it again, from this height, would it fall faster?", they'll say "yes". And if I say "and what if I put an even heavier weight in it, would it fall faster?" again, they'll say "yes".  "And what would fall faster, this ball, or a truck?", they'll say "the truck! of course!". "And would it be much faster, or a little bit faster?", "much faster!".  These are very intuitive, but wrong.  And at these distances, for these objects, air resistance doesn't come into it. They will be landing at (pretty much) exactly the same time as each other.
So, if in response to the textbook explaining how gravity works, and demonstrating the concept that, counterintuitively, gravity accelerates all objects equally, and that it doesn't matter how heavy you make something, it simply won't fall faster than 9.81m/s^2, even though that feels wrong, if someone says:

"Obviously gravity doesn't accelerate all things equally, I could drop a feather and a bowling ball and the ball would drop first."

then they're saying a dumb, wrong thing. Not only have they not understood the concept that they're being taught, they even think they're being smart by "seeing through" the textbook's "obviously" wrong example. Actually, all they've done is not understand the lesson at all, and introduce confounding variables that obscure the concept in order to "disprove" it. They've not understood the concept they're being taught, and yet they think they have provided a counterargument to it, one that shows how obviously wrong it is. >

thanks for the response. I wouldn't necessarily say a response like that is stupid, because someone could just be unaware of air resistance. a better analogy, perhaps, is if the physics book seemed to imply that anything you drop will hit the ground at the same time, to which someone would point out the counterexample of a feather, thus leading them to the conclusion that there are more variables at play, but yes the core principle makes sense. i think thats how i would treat the economics situation im in. obviously, i understand the superficial idea, but i challenged the implication. it should be clear and easy to respond to my challenge by saying the equivalent of 'yes, air resistance exists, but this was strictly talking about an instance of limited variables to make the basic point about acceleration.' Instead, it seems like people do tend to extrapolate the superficial principle to instances where it no longer applies, ignoring the complexity, and thats the issue. because now there are people essentially denying that the feather would drop slower, because they're so fixated on the idea of gravity accelerating all things equally, when instead they should recognize the distinction. what led me to make this post was exactly that—people weren't even recognizing the distinction i had found, thus further making me question whether the book was actually just incorrect or if I was simply wrong >

Imagine you have a shopping list. You MUST buy the 2 items on your list and you must buy them today in order to meet an important deadline.  
One item is office paper. There are two stores in town that sell it: 
Store A is across the street - sells for $50.
Store B is 10 minute drive - sells for $40.  
The second item is a new heavy duty office printer/scanner. There are again two stores that sell it:
Store X is also across the street - sells for $5000.
Store Y is 10 minute drive - sells for $4990.  
Assuming the 10 minute drive cost of gas is negligible (maybe a buck), wouldn't it make equal sense to drive both distances to save the $?  
This is what the textbook example was describing. Any variance in this scenario changes the best course of action entirely. I.e. if there is no urgency to making the purchase, if the purchase is not really necessary, etc. >

Lazily, I'm going to award the !delta here even though others have also brought this up, just as a reference for anyone else who may be interested.
Basically, as you say, the economics textbook provided a scenario with very restricted/specific conditions, and then used that to demonstrate its point that relative change in value doesn't matter, but rather absolute/total change. The broader point of total cost vs benefit actually maps onto my scenarios: 49$ off a 50$ hat absolutely obliterates most of the total cost, whereas 49$ off a 50,000$ tractor barely dents it. Thus, in the latter situation, most of the cost in the tractor is retained, and thus it makes logical sense to not be that compelled by this change in value. HOWEVER, at a superficial level, one can still say that 49$ was saved in either case.
So I still disagree that acting to save 49$ on the hat necessitates that I also act to save 49$ on the tractor (to be logically consistent), because that requirement only makes sense if the restricted/specific conditions of the hypothetical are maintained as well. It seems clear to see that the underlying principle of 'acting to save x' does not necessarily maintain when the conditions are different. >

I think something implicit here that needs to be mentioned outright is that $1 for that $50 hat is probably the best deal you'll ever see on that hat. So it makes sense to jump on the deal. 
Versus the tractor being $49 off? If it's not urgent, you might as well wait and see if a better deal comes. There's a possibility you'll save a lot more by waiting. 
That's why the conditions matter so much. $49 isn't the same $49 anymore if in one case it's an unheard of deal and in the other case it might get better. That's why we need restrictions for the textbook example to work. If we somehow knew that the tractor would never go on sale again, then it should be worth just as much to snatch that $49 deal as with the hat.
In the gum analogy, it totally depends on how badly you need that gum. Say you're on your way to a first date and you realize your breath stinks and there's no time to go home and brush your teeth. That gum is your only hope at not ruining the date? Then yeah I'd pay $10.50 for it. But if there's no rush and you can wait for a better deal somewhere else? It would be rational to wait. 
In the end, it's about getting the best deals and ending up with the most total value. That value includes the restrictions on when you need things. >

Not OP, but this is a great point. Time constrained deals matter! >

You're acting as if the total percentage of the cost is relevant. Why though? Either way you'd have $49 more in your bank account than you would have otherwise. And that $49 will spend just as well.
You're falling into the fallacy. "The price has hardly changed." But that's not what actually matters, what actually matters is the dollar amount. Saving 99% vs 1% doesn't matter because you don't spend percentage points, you spend dollars >

this entails the absurdity of you either A) not picking up the hat for 1$, or B) you jumping on the opportunity to save 49$ off a 50,000$ tractor. neither of which make sense to me. >

Just because it's absurd doesn't mean that it's not rational, it just means that humans are so irrational that rationality feels intuitively absurd. >

in this case absurd is meant to represent an irrational conclusion >

Yeah but it doesn't, you just keep insisting that people would obviously make the different choices, but you don't engage with what exactly makes that rational, if not a material benefit. >

okay, so is it irrational to not want to buy 50c gum for 10$ if you would otherwise pay 10$ more for your 50,000$ tractor, assuming in both cases you showed up to the store to buy them? >

Let's say there are two stores (and you only have time/gas to go to one of them). You need a 50k tractor and 10c gum.
One sells the 50k tractor for 49000, but in order to get that deal, you need to buy the 10c gum at $100.
The other sells the 50k tractor for 50k and the 10c gum for 10c.
Which one do you go to? >

the former >

okay. Let's change it to 50k tractor for 49900.10 and 10c gum for 100. Would it matter which store you went to? >

dont think so >

You're really cherry-picking your scenario.
What if I do need the tractor urgently, and it's not going to cost most more than $49 to buy it from the seller that has it for less?
What if we replace $49 with $1,000 and replace "a hat" with a 75" 4k OLED TV?
I could get the TV practically for free (say 99% off), but I'm perfectly happy with my TV and don't want to deal with the hassle of getting a new one and setting it up.  Conversely, my tractor is costing an arm and a leg in repairs as it ages, and new ones never go on sale.  I'd be a fool not to take advantage of a rare sale and get something that will help me perform my job for years to come.
Point being: it can be rational to jump.  It can be rational not to jump.  There's more than just percentages to look at.