What was the last time you had your "mind blown"?

[DaveSumm]

Finding out that the ‘indian’ guy in Short Circuit was Fisher Stevens. Holy shit could you not get away with that today.

[Tears of Lys]

On ‎6‎/‎28‎/‎2018 at 7:53 PM, Aemon Stark said:

It's a dodgy one. One staff I've worked with calls ketamine "dreadful". 

It was a "unique" experience to be sure.  I've never experimented with LSD, but I'd imagine it's somewhat similar.  The anesthesiologist was trying to coax me into happy thoughts before he administered it, which was somewhat difficult to do since I was writhing in excruciating pain. 

When I had it set by the orthopedic surgeon the other day, the anesthesiologists there administered a nerve block in two places, which rendered the area numb, and put me into the old tried-and-true "twilight sleep," which I MUCH prefer. 

It didn't help that the first anesthesiologist, with the ketamine, gave off a distinct vibe of being the Stanley Tucci character from the Lovely Bones movie.   

[Mladen]

I hopped on body weight scale and saw the three digit number...

Needless to say my mind still finds it way back to the skull... 

How the hell am I going to lose all that weight?

[FunFalconryFacts]

On 6/29/2018 at 8:06 PM, Werthead said:

When I first encountered someone who honestly believed that manmade climate change was impossible because the climate had changed in the past when humans weren't around. I honestly couldn't understand what they were talking about until I realised that they believed that it was a zero sum game: humans had to be responsible for all climate change or none climate change. The idea that humans have instead interfered with natural processes that were occurring anyway, and have dramatically accelerated pre-existing trends (or perhaps even reversed them catastrophically), was a concept literally beyond their mental ability to grasp.

My mind was blown that day, as I had to dial down my lower end of expectations for adult human intelligence considerably.

What sometimes blows my mind is that there are adults who are not stupid, who believe incredible things. I used to know an extremely intelligent man who believed that 9/11 was an inside job, after watching Youtube videos and swallowing things that could be debunked with ten minutes on Google. Similarly, religious people who are perfectly intelligent, who believe that the earth is 6000 years old, because they have grown up in a community where everyone believes that, and human beings have a very powerful need to belong to the tribe, and it is extremely difficult/frightening to break away and be the one who doesn't believe.

 

So that's my mind-blowing moment - not that there are people who believe these things, but that a lot of them are perfectly bright. The human mind is a powerful computer, and even the cleverest among us are poor programmers. 

[Maithanet]

There's a mathematical principle that I can't remember the name of but one of my friends explained it to me a month or so ago and it kinda blew my mind.  It's basically that we don't take into account different sample sizes well in calculating a whole, but the result is that you can get a situation like this:

1. Steph Curry shot a higher field goal % than Lebron James in the first half. 

2.  Curry also shot a higher percentage in the second half. 

3.  Lebron James shot a higher percentage for the whole game. 

 

How could that be possible?  Well when you sub in real numbers it's obvious how it might happen.

First half Lebron shoots 0/3, Curry shoots 1/10.  10% is higher than 0%.

Second half Lebron shoots 8/10, Curry shoots 3/3.  100% is higher than 80%. 

Full game line:  Lebron shot 8/13 (62%), while Curry shot 4/13 (31%).

 

Mind = Blown.  Also, does anyone who knows more math than me remember the name of this phenomenon?  It has a name. 

[dbunting]

On 7/5/2018 at 1:49 PM, FunFalconryFacts said:

What sometimes blows my mind is that there are adults who are not stupid, who believe incredible things. I used to know an extremely intelligent man who believed that 9/11 was an inside job, after watching Youtube videos and swallowing things that could be debunked with ten minutes on Google. Similarly, religious people who are perfectly intelligent, who believe that the earth is 6000 years old, because they have grown up in a community where everyone believes that, and human beings have a very powerful need to belong to the tribe, and it is extremely difficult/frightening to break away and be the one who doesn't believe.

 

So that's my mind-blowing moment - not that there are people who believe these things, but that a lot of them are perfectly bright. The human mind is a powerful computer, and even the cleverest among us are poor programmers. 

Funny I see this today. Had a discussion at work a few weeks ago and a guy here, who has a degree... doesn't believe the world trade centers went down because of the planes, because steel melts at over 2000 deg and jet fuel only burns between 800 and 1500 degrees, therefor it's not possible..and "people" heard explosions in the lower levels that day.

I couldn't hide the look on my face when he said it. I tried to explain to him that the heat from the fuel was only part of it, that the impact of the plane itself was a huge factor in weakening the structural steel but he wasn't having any of it, said you guys can be sheep and believe what you want!

Now for the reason that it blew my mind...we work in a FUCKING steel mill! We know, or for fucks sake should know that you don't have to melt steel to weaken it! And we have metallurgists here who can explain just how easy it would be for it to happen like it did. I even pointed out that when bending steel bars you don't melt them you simply heat them until you can bend them, he just shook his head and called us sheep!

[Jo498]

I don't know a proper name for the percentage paradoxon, but it is similar to the distinction between extensive and intensive magnitudes. If you add two units of water the result has twice the volume and the mass of the parts because these are extensive magnitudes that are simply added to get the result for the whole. But if each unit was at 20° centigrade, the result will also be at 20°, not at 40°, obviously, because temperature is an intensive magnitude.

[maarsen]

3 hours ago, Jo498 said:

I don't know a proper name for the percentage paradoxon, but it is similar to the distinction between extensive and intensive magnitudes. If you add two units of water the result has twice the volume and the mass of the parts because these are extensive magnitudes that are simply added to get the result for the whole. But if each unit was at 20° centigrade, the result will also be at 20°, not at 40°, obviously, because temperature is an intensive magnitude.

In physics class in high school, we were taught that length, volume and such are scalar quantities, velocity and acceleration and momentum were vector quantities. These can be added using the proper rules. Things like temp or percentage cannot be added because they are not quantities but a function of something else. 

[Iskaral Pust]

Unfortunately it has recently been the stupidity of fellow homo "sapiens" that blew my mind:

- a seemingly intelligent colleague with a post graduate degree sent an email to several senior colleagues that used global warming as a supposedly relatable analogy for something he believes is a conspiracy of empty virtue signaling that everyone knows is false but required to pay lip service (in corporate politics).  He specifically referred to the absurdity of "cow farts" changing the climate.  I don't know if I was more surprised that he thinks global warming is a hoax or that he assumed we all did too.

- my son's math teacher, with previous experience as a high school math teacher, taught my son's class a distributive method for division, i.e. (5/8 = (2+3)/(4+4) = 2/4 +3/4), and insisted they use it for their homework.  After angry parents sent kids back to class the following day, she had to consult another colleague to understand why it didn't work.

- the 2016 presidential election.  Trump's approval rating above 40%.  Some things I just cannot fathom.

- the flat earthers.  I finally read what that was all about and the experiments they conduct, e.g. from airplanes, to prove they are right.  Holy fuck.

[Jo498]

15 minutes ago, Iskaral Putsch said:

- my son's math teacher, with previous experience as a high school math teacher, taught my son's class a distributive method for division, i.e. (5/8 = (2+3)/(4+4) = 2/4 +3/4), and insisted they use it for their homework.  After angry parents sent kids back to class the following day, she had to consult another colleague to understand why it didn't work.

This is mind blowing. How can someone who never mastered fractions (5th- 6th grade) become a math teacher?!?!

[Iskaral Pust]

2 hours ago, Jo498 said:

This is mind blowing. How can someone who never mastered fractions (5th- 6th grade) become a math teacher?!?!

This lady was a piece of work.  Every time I asked my son about math class my blood pressure would go up another ten points.  He basically did no math for the entire 5th grade.  We did math at home with him each evening for the curriculum he should have followed.

[Jo498]

This is a disgrace. A teacher does not have to be perfect, of course.

I remember one or two lessons with my somewhat fuzzy-headed teacher in 12th grade math when the whole class was quite frustrated because nobody including the teacher could do a bunch of integration exercises. Some substitution trick (or sth. like that) was needed and the teacher apparently had not prepared well and forgotten about that trick. I don't remember how it was resolved in the end (only that when I learned that stuff again at university I remembered that episode and it was not such an outlandish trick and once one knew about the trick the integrations were not difficult). This can happen with advanced or optional material a teacher himself encounters only every few years.

But it should not happen with fractions in 6th grade...

[Jen'ari]

Madison Square garden on Tuesday night, blown in a good way .

[chuck norris 42]

On ‎7‎/‎6‎/‎2018 at 4:08 AM, Maithanet said:

 

First half Lebron shoots 0/3, Curry shoots 1/10.  10% is higher than 0%.

Second half Lebron shoots 8/10, Curry shoots 3/3.  100% is higher than 80%. 

Full game line:  Lebron shot 8/13 (62%), while Curry shot 4/13 (31%).

 

Mind = Blown.  Also, does anyone who knows more math than me remember the name of this phenomenon?  It has a name. 

If you combine groups and get a different result than the individual groups  it is called Simpsons paradox, However I would argue it specifically deals with lurking variables so it is really about keeping separate groups separate. 

Simpons Paradox example In a hospital 

88 out of 98 of Doctor Nick's  patients  with minor  injuries live (89.8%)
91 out of 100 of Doctor Hibert's patients with minor injuries live (91%)

1 out of  2 Doctors Nick's patients with major injuries live (50%)
5909 out of 9900 Doctor Hibert's patients with major injuries live (59.7%)

Doctor Hibert has a Higher survival rate  than Nick so Hibert is the  better Doctor

If you use the totals you get the opposite answer 

89 out of 100 of Doctor Nick's patients Live (89%)

6000 out of 10,000 of Doctor Hiberts patients Live. (60%)

It is stupid to conclude Doctor Nick is a better doctor because He has a higher survival rate , What is actually going on is that if  your doctor is Doctor Hibert you are screwed because he deals with most of the Major injuries and you probably have a major injury. If your doctor is Doctor Nick you probably are not seriously hurt.

 

Your basketballer example is the same my example in one major way, the total is the opposite of the individual parts, 

However
in your example the total is better than the individual parts 

Also are percentages the best way to measure a basketballer? Is 3/3 really better than 8/10?

 

 

 

 

 

 

 

 

 

 

 

[Maithanet]

18 hours ago, chuck norris 42 said:

If you combine groups and get a different result than the individual groups  it is called Simpsons paradox, However I would argue it specifically deals with lurking variables so it is really about keeping separate groups separate. 

Your basketballer example is the same my example in one major way, the total is the opposite of the individual parts, 

However
in your example the total is better than the individual parts 

Also are percentages the best way to measure a basketballer? Is 3/3 really better than 8/10?

Simpsons paradox was the one, thank you. 

And while you could argue that 8/10 is a better stat line than 3/3 (really it would depend on the context), it is undeniably a lower shooting percentage. 

[Erik of Hazelfield]

Ok, I’ve got one. 

Let’s say you have a large ball that is one meter in diameter, or about 3 feet. Let’s then say you tie a string tightly around the ball so that you get its circumference. The circumference would then be pi times the diameter, i.e. 3.14 meters in our case.

Now, let us lengthen the string with one meter and put it back. The question is: how far above the ball’s surface would the string float? 

The circumference of the new sphere would be pi plus one meter, so 2*pi*r +1 = 2*pi*rnew. Solving for the new radius rnew, we get:

rnew = (2*pi*r+1)/(2*pi) = r + 1/(2*pi)

This means the string will float 1/(2*pi) = 0.16 meters above the ball, or about 6 inches for those of you accustomed to that. That seems about right, no?

But wait a minute! If the string would float 1/(2*pi) meters above the ball - there’s no dependence on the radius included in that expression! If you lengthen the string with one meter, you will ALWAYS have it float 16 cm above the ball’s surface regardless of its diameter. You can have a ball the size of the bloody EARTH and if you lengthen the string with one meter, the string would still float 16 cm above its surface - all around the globe! 

Quod erat mindblowandum.