HomeLatest ThreadsGreatest ThreadsForums & GroupsMy SubscriptionsMy Posts
DU Home » Latest Threads » Forums & Groups » Main » General Discussion (Forum) » Some people need a math l...

Wed Dec 20, 2017, 11:27 AM

Some people need a math lesson.

A reduction from 35% to 21% IS NOT a cut of 14%. It is a cut of 40%.
Do the math.

18 replies, 2859 views

Reply to this thread

Back to top Alert abuse

Always highlight: 10 newest replies | Replies posted after I mark a forum
Replies to this discussion thread
Arrow 18 replies Author Time Post
Reply Some people need a math lesson. (Original post)
BillyBobBrilliant Dec 2017 OP
unblock Dec 2017 #1
pangaia Dec 2017 #17
PoindexterOglethorpe Dec 2017 #2
FakeNoose Dec 2017 #5
robbob Dec 2017 #11
PoindexterOglethorpe Dec 2017 #13
robbob Dec 2017 #14
PoindexterOglethorpe Dec 2017 #15
robbob Dec 2017 #18
dawg Dec 2017 #3
MineralMan Dec 2017 #4
SCantiGOP Dec 2017 #6
Cryptoad Dec 2017 #7
alwaysinasnit Dec 2017 #8
SHRED Dec 2017 #9
Moral Compass Dec 2017 #10
Maraya1969 Dec 2017 #12
Iggo Dec 2017 #16

Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 11:33 AM

1. correct, and this is one of the reasons some people get fooled into thinking cuts pay for themselves

with top taxes going from 39.6% to 37%, people think that seems like a small cut and therefore the economy only needs to grow a little to recoup the revenue.

in fact, the cut of 2.6 percentage points amounts to a cut of over 6.5%.

so the economy would have to increase by 6.5% solely due to the cut in the top income tax rate in order for the government to break even on revenue.

this effectively impossible. the economy is not going to grow at a 6.5% rate, and it's certainly not going to grow at a rate 6.5 percentage points faster than it's already growing -- remember we're not in a recession!

Reply to this post

Back to top Alert abuse Link here Permalink


Response to unblock (Reply #1)

Wed Dec 20, 2017, 11:13 PM

17. The economy would have to grow at MORE than 6.5%

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 12:08 PM

2. Most people have completely forgotten how to do basic math.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to PoindexterOglethorpe (Reply #2)

Wed Dec 20, 2017, 12:21 PM

5. That's what the GOP is counting on

American high schools do not teach critical thinking skills.
Most high school graduates took some math but they've forgotten the important stuff.
Or they just don't care because it's easier to believe the lies.



Reply to this post

Back to top Alert abuse Link here Permalink


Response to PoindexterOglethorpe (Reply #2)

Wed Dec 20, 2017, 02:41 PM

11. I am constantly astounded by peoples lack of basic math skills

I discovered an interesting math puzzle the other day called the Monty Hall problem, so named because of the ďLetís Make a DealĒ game show set up.

https://betterexplained.com/articles/understanding-the-monty-hall-problem/

The set up is simple. There are three doors, behind one of which is the grand prize typically ďA NEW CAR!!!Ē

The game show host gets you to pick a door. Before opening it he goes to one of the other remaining doors and opens it to reveal a booby prize usually something of a joke like a goat. Then he asked you do you want to stay with your first guess or do you want to switch to the one remaining door.

The question is, should you stick with your original guess or switch to the remaining door that hasnít been opened yet? Or does it even make a difference if you stay with your original guess or switch? The answer may surprise you; if you like these kind of brainteasers I highly recommend the link above. Spoiler alert! Iím going to give the answer away so if you enjoy working out a problem donít read any further!

Anyway, I was explaining this problem to some friends one of whom is a medical doctor. She insisted that it didnít matter if you switch or not because with two doors remaining the odds are 50-50 that the prize could be behind either door.

Hereís where I had to shake my head at the lack of math skills in an otherwise very intelligent person. To illustrate the point that you should ALWAYS switch to the remaining door I asked her, what if you started with 100 doors? You pick one door so your chances are one in 100 of having the right door and then Monty Hall opens all the other doors except for one and then asks you if you should stick with your original guess or switch.

At this point I expected a lightbulb to go on, but no, she insisted that with two doors remaining the odds of having the prize behind either door was still 50-50 and therefore it didnít matter if you stuck with your original pick or switched. No amount of arguing could change her mind. I was absolutely flabbergasted. My conclusion was, some people get math and some donít.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to robbob (Reply #11)

Wed Dec 20, 2017, 04:30 PM

13. That particular problem is a little tricky for most people, even

some math geeks.

And oddly enough, when I went to that site and started playing, I lost more than I won. I played 20 games, which would seem to be a fair trial.

So maybe the claim you should always switch doors is wrong, and that notion that you still have a 50-50 chance is the correct one.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to PoindexterOglethorpe (Reply #13)

Wed Dec 20, 2017, 05:48 PM

14. Absolutely wrong!

Sure, I can flip a coin 10 time and get it to come up tails 9 times, that doesnít change the fact that mathematically speaking, head vs tails is a 50/50 probability! Try playing the game with 10 doors; over time you will be wrong to stick with your original pick 90% of the time!

Put another way; when presented with 3 doors, you have a 33% chance of getting the correct door. So there is a 66% chance the correct door is one of the other 2. Monty shows you the ďother doorĒ that doesnít have the car, but that doesnít change the odds: there is still a 33% chance your first pick was right, and a 66% chance the car is behind the other door.

This mathematical fact does not take into account human intuition...

Reply to this post

Back to top Alert abuse Link here Permalink


Response to robbob (Reply #14)

Wed Dec 20, 2017, 09:29 PM

15. I've been reading about this problem for years now,

and I've always trusted the math. I did find it rather odd that with 20 picks I was barely above 50%. Yeah, I do know that there can be goofy runs, and that the more times you do it the closer you'll get to the correct (predicted) outcome.

But that really is a poor example to use to demonstrate how people don't understand math, since everyone has seen that show and to change your pick is extremely counter-intuitive. A lot of math is not intuitive, I know.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to PoindexterOglethorpe (Reply #15)

Thu Dec 21, 2017, 12:13 AM

18. Yeah, I know, not a great math example

Last edited Thu Dec 21, 2017, 01:09 AM - Edit history (1)

With only three doors it does seem counter intuitive. And with only three doors it would be possible to have quite a run of luck always sticking with the same door. I guess the part that blew my mind was when I switched the example to be based on 100 doors. As I mentioned in my post my friend was still convinced it was a 50-50 proposition even starting with 100 doors. By that logic you could show somebody 1 million doors and ask them to pick one and then eliminate all the other doors but one. According to my friend it would still be a 50-50 chance to stick with the door you originally picked or switch to the only remaining other door out of 1 million. Thatís what I meant when I said some people have a very questionable understanding about math and probability.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 12:14 PM

3. We're an innumerate society.

Once you accept that fact, everything else starts to make sense.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to dawg (Reply #3)

Wed Dec 20, 2017, 12:18 PM

4. And functionally illiterate, to boot.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 01:19 PM

6. People is dumb

I worked for a county years ago. We had trouble explaining to people that in order to get the homeowner's 4% assessment on their houses instead of the 6% that applied to rental units they had to come to the Courthouse and apply.
It was amazing how many people came in and said they had not applied because it wasn't worth the trip for just a 2% difference, but their tax bill was 50% than neighbors with comparable priced houses.
I really, really wanted to tell them that the 50% difference was the County's Stupidity Tax.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 01:31 PM

7. Welcome to DU,,,,,Comrade!

I can see you are not schooled in GOP Math.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 01:41 PM

8. math lesson

The trashing of the public education system over the last 3 decades by the GOP, I believe, is a huge factor.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 02:18 PM

9. BINGO

 

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 02:24 PM

10. Absolutely correct

Much of what is going on in this country from a political and a business perspective hinges on the average citizens mathematical illiteracy.

Some of it is basic arithmetic such as calculating percentages. But some of it is complete ignorance of powerful mathematical concepts such as compound interest.

American business has become reliant on predatory business practices where what is in the fine print can destroy you or at least seriously damage you.

This essential ignorance is what is making the world go around and what makes our Republic so incredibly vulnerable. How do you know to say no when you canít even perceive the magnitude of what is being proposed?

Dropping the corporate tax rate from 35 to 21 looked huge to me the whole time, but if you were instead thinking it was 14% reduction it probably looked a lot smaller.

That this passed without any loopholes being closed means that a lot more companies will pay close to nothing.

This is a disaster but Iím afraid few will recognize it until it impacts them.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 04:03 PM

12. People also do not consider how much a cut in the government's income will affect the country

Remember how Hillary was going to increase the tax on the top 1% and use that money for infrastructure?

Now there is no money to do anything like that

Reply to this post

Back to top Alert abuse Link here Permalink


Response to BillyBobBrilliant (Original post)

Wed Dec 20, 2017, 10:20 PM

16. Am your children learning?

Reply to this post

Back to top Alert abuse Link here Permalink

Reply to this thread