Simple Question

[Anonymous No.13733814]

A lot of you here seem to think you're smart and can beat the markets by actively trading stocks/crypto. I have a simple logic/probability question that we ask the incoming software devs (college level) in our fund, can you answer it?

I take an ordinary-looking coin out of my pocket. I flip it 3 times and it is always heads. What is the chance that the next flip is also heads?

What would the chance be that the next flip is heads if I had flipped the coin 100 times and every flip resulted in heads?

[Anonymous No.13733822]

>>13733814
>What is the chance that the next flip is also heads?
50%
>What would the chance be that the next flip is heads if I had flipped the coin 100 times and every flip resulted in heads?
50%
anything else faggot?

[Anonymous No.13733853]

>>13733822
this is incorrect, you would not get the job. I emphasized that the coin only looks ordinary - it could be weighted.

[Anonymous No.13733862]

>>13733822
that's actually incorrect, there's some mathematical law(i forgot the name) which states something along: If you repeat some action and it results in certain outcome(A) with each repetition probability of outcome(B) is increasing...

I think in case of coin toss the probability shifts very slightly but still it doesn't remain on the 50%

[WhaleKiller !!GkZaQSwrrji No.13733905]

>>13733814
Each coin toss could theoretically alter the weight distribution each time it's flipped, if even only by a few atoms which would then alter the probability

There is no right answer and the real answer to your question is for the interviewee to ask as many questions to gain as much information to maximize the probability of guessing the correct outcome

[Anonymous No.13733915]

+-1

[Anonymous No.13733918]

>>13733814
If anyone asked me some immature "gotcha" shit like that, I would turn right the fuck around and work somewhere else, no amount of money justifies that level of childishness

[Anonymous No.13733923]

>>13733853
Yea well your imaginary coin toss is always a 50/50 chance in hypothetical land.
Or else its not an imaginary coin toss.

[Anonymous No.13733934]

>>13733814
>>13733853

it could also be a fucking dinosaur if it just looks ordinary

[Anonymous No.13733936]

>>13733814
This is the most retarded thread I have ever seen
You literally saved a picture of a meteorologist's desk and saved it as tradedesk.jpg

[Anonymous No.13733951]

>>13733814
this is not a logic question, it is a semantics trick. you are a bad interviewer if you’re asking this question because almost no one gets t right the first time.

t engineering manager

[Anonymous No.13733953]

>>13733814
to flip this coin 100 times and get the same result is almost statistically impossible therefore it must be a double sided coin

[Anonymous No.13733955]

>>13733936
>he doesn't know about weather based derivatives

why am i not surprised?

[Anonymous No.13733972]

>>13733905
>>13733918
>>13733923
this is all wrong. There is a definite probability model that you can construct, without needing more information.

I guess a better way that you people would understand is this:

We are observing a combination of technical indicators. Whenever all our technical indicators are met, stock A has gone down (the two choices being up/down, not going to add complexity by introducing percents).

We observe 3 instances where the indicators were met, and the stock price went down. What would be the chance that it goes down the next time all our indicators are met?

What if we observed 100 instances where the indicators were met, and the stock price went down? What would be the chance that it goes down the next time all our indicators are met?


>>13733936
it was the first thing on google images that didn't have someone's face on it, but that's actually funny as fuck. We actually have a former climate modeling guy working for us though.

>>13733862
This anon is on the right path

[Anonymous No.13733981]

Fuck you and your meme interview questions.

Cocksucker

[Anonymous No.13733987]

>>13733814
is it one of those questions where the answer is not important but the way you think about the problem?

[Anonymous No.13733999]

>>13733951
hopefully its not civil engineering so I don't have a bridge collapse on my head

>>13733953
the point is that the coin doesn't have a 50/50 chance of going heads/tails

>>13733987
both are important; though there is a definite answer (formula) that you could present. This isn't a question like "how many ping pong balls fill up a skyscraper" where you just tell us how you would get to the answer

[Anonymous No.13734002]

>>13733853
The wind could also blow on it while it's spinning in the air too, this is retarded and the winning answer is to not play OP's dumb game

[Anonymous No.13734011]

>>13733862
you can't be serious

[Anonymous No.13734019]

The chance of it not being heads increases with every flip.

[Anonymous No.13734048]

>>13733814
What are the odds that you’re a boomer faggot who likes to feel smug asking dog shit meme questions to candidates in an environment that’s already uncomfortable for them ?

[Anonymous No.13734065]

>>13733814
>>13733862
probability of r heads in n flips = (n nCr r)(p)^r(q)^n-r
probability of 4 heads in 4 flips = (4 nCr 4)(0.5)^4(0.5)^0 = 0.0625 = 6.25%
probability of 100 heads in 100 flips = (100 nCr 100)(0.5)^100(0.5)^0 = 7.89x10^-31
What do I win

[Anonymous No.13734070]

>>13733862
Those are not mathmatical rules. Those are boomer laws. Such as the law of averages. Stupid nonsensical rules made up by boomers assuming that just because something is statistically possible that it is inevitable.

[Anonymous No.13734074]

>>13734048
i'm 26. also, we want candidates who are able to perform logically under high pressure trading situations

[Anonymous No.13734076]

>>13734048
No I bet the odds are he would kill for being able to offer gains to institutional clients in a day that they are struggling to offer for a year and is smart enough to realise this market currently doesnt operate like traditional stocks

[Anonymous No.13734079]

>>13733814
You havn't stated that there is any other option besides heads.

[Anonymous No.13734080]

>>1373407
And a biiig fuck you to you cocksucka. Shove your meme brainlet fucktard questions up your mothers cunt.

[Anonymous No.13734106]

>>13734065
this doesn't answer my question (which is asking what happens to the NEXT flip) and is also wrong (you're assuming it's a fair coin flip, which the question strongly suggests its not). The real question would then become how you got an interview in the first place.

>>13734079
>>13733972
see my rephrasing of the question using a stock whose price either goes up and down

[Anonymous No.13734134]

>>13734106
If its not a fair coin flip, then you might as well ask what are the chances of op being a faget. Its 100% btw.

[Anonymous No.13734144]

>>13733814
>ordinary-looking
So its a weighted coin. And you're asking me if I can extrapolate the past out into the future or not. Well since you rigged it and maybe you have a switch on it. I can't extrapolate the past. So the question then is, are other people extrapolating the past? If yes then I sell cause they're all stupid and wrong.

[Anonymous No.13734166]

>>13734106
to get the probability of the next flip, you d use Bernoulli's trails with a binomial coefficient for a fair coin flip, and questions like these makes you sound like a smug uneducated boomer

[Anonymous No.13734177]

ITT: OP is a faggot and anons failed basic probability class.

[Anonymous No.13734179]

>>13734166
yes, if it was a fair coin any middle schooler could answer the question. the point is that is not. since everyone seems to be stuck on the fact that coins have to be 50/50, please refer to my rephrasing of the question here:

>>13733972

[Anonymous No.13734197]

>>13733936
lol

[Anonymous No.13734239]

>>13733814
You're a fucking faggot OP, save this shit for the Math fair you fucking loser. Post your yearly gains or fuck off. Imagine taking this kind of shit from some faggot fund manager that made a 5% return. Wage cucks needs to start unironically lynching fags like you

[Anonymous No.13734311]

Op is a faggot cocksucker

[Anonymous No.13734411]

>>13734106
is this a bayesian analysis question into which you can put a probability calc like "likelihood of weightedness given unlikelihood of the current state of the test"?

[Anonymous No.13734419]

>>13733814
50% both cases

[Anonymous No.13734427]

>>13733999
bridges are made with word puzzles? ok.

[Anonymous No.13734449]

>>13733814
50% in the first case, 100% in the second case. Approximately. Btw the data is not sufficient to answer the question: it depends on the probability that you would carry around a weighted coin.

[Anonymous No.13734509]

>>13734239
This is a bullish sign and the op is probably low to mid level at a trading firm who told his manager to leave it to him to scout talent. They know whats happening and going to happen and although they have traditional trading skills the mindset wont work for now in this arena. More and more larger firms will come here scouting for talent and some anons will get taken on. What the traditional firms dont realise it that a paradigm change has occurred and its going to be difficult to attract talent from this arena without massive incentives. why would anyone wagecuck without the potential for massive wealth when they can trade shitcoins themselves? There may be some opportunities for anons to ride this wave for big firms should they so disire. Cant blame the op for seeking an opportunity maybe he will jack his job in and do this himself ha

[Anonymous No.13734510]

If your triggers are met 100 times in a row with that level of predictability, you aren't flipping a coin at that point anon. The quarter is just for show.

[Anonymous No.13734528]

>>13733814
LARP

larper go

[Anonymous No.13734544]

>>13733814
Nice bait thread, I'm impressed.

[Anonymous No.13734948]

And this is how you turn away real talent and get incompetent soiboys instead given you're not in the top 25 companies.
The more you know!

[Anonymous No.13734991]

>>13733862
depends if you use a discrete approach or an continous. continous would be what you sat, discrete is the 50% approach. the more you're connected the likely continous, the more vertical the more likely its gonna be discrete independent 50% tosses. yes im a genius, dont ask.

[Anonymous No.13735106]

Assuming that you are not lying, the next flip is heads. In your own words "it is always heads."

For the anons in this thread that don't get it, the purpose of the question (as it applies to a software developer) is to see how well you listen to clients. It is very important to develop software that meets the exact needs communicated by the client, in exactly the way they want those needs met, without getting too "creative."

[Anonymous No.13735396]

>>13733951
This. OP is probably some 90 IQ HR roastie who thinks getting candidates to solve fucking riddles is a good interview process.

[Anonymous No.13735431]

>>13733814
Look, I know what you're getting at. But let me just say, I'm a SUCCESSFUL daytrader using very advanced technical analysis, and my gaynes are DEFINITELY NOT RANDOM.

[Anonymous No.13735473]

>>13733853
or it could not be weighted, faggot

[Anonymous No.13735490]

>>13733862

i flip 100 coin head that mean every coin make flip more head

[Anonymous No.13735504]

>>13733953

>except it isnt statistically impossible
>therefore it musn't be anything other than the information given by OP

[Anonymous No.13735515]

If you flip 100 heads in a row your assumption about the coin being fair is most likely incorrect.

[Anonymous No.13735518]

>>13735515
yeah, so you investigate, rather than concluding its weighted based on nothing but your imagination.

[Anonymous No.13735532]

>>13733853
i would fucking shank you

[Anonymous No.13735579]

>>13734449
Oh, now that I think about it again, we can look at the odds that this woyld happen by chance. In the first case, the probability of getting heads again is 15/16. Second case is 1 - 2^101, that is so astronomically low it's not worth calculating.
However these are a posteriori probabilities, they rely on ulterior assumptions or some shit.

[Anonymous No.13735630]

>>13735518
>nothing but your imagination

The results of 100 trials is empirical evidence, not my imagination. I would conclude that we are most likely not dealing with fair coin, and that is the end of the homework problem. Goodnight, kid.

[Anonymous No.13735696]

>>13735630
what you drew from the evidence is your imagination

enjoy being sub 80 IQ, I wonder how much you've lost in crypto

[Anonymous No.13735701]

>>13735579
Why don’t you give the magic formula, jackass?

[Anonymous No.13735722]

>>13735696
I'm up about 2k. Not much but as a % of total fiat deposits it pretty good. Thanks for asking.

[Anonymous No.13735799]

op is a HUGE fukn FAGGOT

[Anonymous No.13735804]

>>13733814
>50%
>About 100%, the flip is rigged

Your hiring standards are modest I see

[Anonymous No.13735876]

>>13733814
>>13735804
Please let me work for you, OP. I'm a well qualified grad.

[Anonymous No.13735916]

>>13733814
U can't beat the crypto markets guise just buy and hodl!

[Anonymous No.13735953]

>>13733814
What about all the times you flipped the coin before we did the 100 count? What if you landed tails 100 times right before you asked this and you didnt tell me?!

[Anonymous No.13735979]

>>13733814
The last coin ricochets and goes straight up your sodding arsehole giving you led poisoning and you die, how that sounds op?

[Anonymous No.13736528]

>>13733814
>ok interviewee, i'm holding five stones and each is a different color
>i ask them to tell me which is my favorite
>stoopid idiots don't ask me if I'm colorblind haha

[Anonymous No.13736609]

>>13733814
Dude. There is a much easier method for determining not only long term and shorter term directional bias, but also where each swing high and swing low is....to the fucking pip, in terms of accuracy.

It all comes down to mean thresholds and standard deviations....of what? Im not telling your ass, OP, because you should be "smart" enough to figure it out on your own.

[Anonymous No.13736673]

>>13733814

In the interview id be like

>check out this Fucking BOoMER with his physical coins hahahahahaa
>sorry I don't work for such obsolete brainlets outfits

Then walk out

[Anonymous No.13736698]

>>13735876
Be a day trader and work for yourself

[Anonymous No.13736701]

>>13733853
Then I guess I'd report you to the SEC for manipulation and insider trading faggot

[Anonymous No.13736706]

If you literally flipped a coin a hundred times and got heads every time you'd literally be a retarded close minded brainlet if you think there wasn't something fucked up with the coin.

[Anonymous No.13736766]

>>13733814
>I take an ordinary-looking coin out of my pocket. I flip it 3 times and it is always heads. What is the chance that the next flip is also heads?

1/16

>What would the chance be that the next flip is heads if I had flipped the coin 100 times and every flip resulted in heads?

1/2^101=whatever dont care do your own homework...

[Anonymous No.13737290]

>>13733814

the answer is i smash you in the mouth and make you squeal like a pig

[Anonymous No.13737347]

>>13733822
Lemme guess, American? This is the easiest probability question in the book.

>>13733853
You're a retard

[Anonymous No.13737585]

OP is confirmed to be 90-130IQ as it not capable of being aware of the true depths of his stupidity.

[Anonymous No.13737597]

>>13736766
>1/16

[Anonymous No.13737664]

>>13733862
You’re thinking of the Law of Large Numbers but you’re misrepresenting it. The law states that with enough trials/samples, it should converge on the true probability. That doesn’t mean that the probability changes each time, which is known as the Gambler’s Fallacy.

[Anonymous No.13737965]

>>why am I responding to a troll thread?

[Anonymous No.13738157]

>>13733814
Why did you take a picture of a ghetto tradedesk from the early 2000's? i could walk up to the trade desk at my office and take pics of traders who use a massive 43" in the center surrounded by 2 32"s on each side

[Anonymous No.13738166]

>>13733814
is biz this retarded....i thought i came to the mecca of professional business investors

[Anonymous No.13738219]

>>13737597
American?

[Anonymous No.13738535]

So op you expect an interviewee to calculate probability just based on the number of times you flip a coin?

Flipping a coin by default is 50%.

But you flipped your coin a 100 times and didn't get a 50% roll.

So do you expect your interviewee to use Bayes or a combination of basic logic 50/50 and a Bayes model?

[Anonymous No.13738546]

>>13738535
bayesed and redpilled

[Anonymous No.13738631]

>>13733814
.75 and .99009

[Anonymous No.13738706]

>>13737965
how do you square this with the law of large numbers? which one has priority?

[Anonymous No.13738823]

>>13738535
if each coinflip is independent (a commonly valid assumption), then Bayes is not needed, since P(A|B)=P(A) when independent events


but OP intentionally worded it so that no matter what answer is given, he can appear "smart"
its a childish loaded question, giving the equivalent of 1 equation with 2 unknowns

there is no right answer, because the question leaves out essential information needed (if standard assumptions are ignored) to get a "right" answer

[Anonymous No.13738876]

Thanks Anon. So pretty much op is a faggot. Thought so

[Anonymous No.13739787]

>>13734074
then you are a roastie.
tits or gtfo.

[Anonymous No.13739814]

>>13733814
>I have a simple logic/probability question that we ask the incoming software devs (college level) in our fund
I wouldn't want to work for a faggot like you.

[Anonymous No.13739882]

>>13733814
>think you're smart

No, I know I'm smart and much smarter than you

[Anonymous No.13739972]

*AHEM*

*TING TING TING*

I have an announcement to make, if you will.

FUCK OP, FUCK NIGGERS, AND LASTLY, FUCK JANNIES

[Anonymous No.13740008]

>>13733814
odds r i giv u a knuckle sandwiche and taek your coin fren

[Anonymous No.13740073]

>>13733853
You must feel so much smarter than those dumb college grads who come through your interviews. What a smart guy.

[Anonymous No.13740089]

>>13733972
Probability and statistics are a meme. You could have all your indicators with raging erections 10 trillion fucking times and you go all in and the stock dumps and all your indicators are BTFO. If you honestly think you can use probability to win in the stock market you are a low tier shit firm and should take lessons from some of the biggest banks and funds in the world who went bankrupt believing the exact same thing. Operating a stock trading firm is about one thing and one thing only: parting people with their money so you can take a percentage. Win or lose is all about luck and eventually it’ll catch up to you.

[Anonymous No.13740139]

>>13740089
Based and talebpilled

[Anonymous No.13740227]

>>13735106
no, the purpose of these types of questions is to make the interviewee feel uncomfortable or dumber than the interviewer. it's annoying as fuck anyone with a shred of self respect doesn't play this kind of game.
interviews go both ways, we are both feeling out whether or not this is going to be a good fit. Why the fuck would I want to work with a cunt like OP, when I know I'm not going to have an issue finding good paying work elsewhere? I will walk out of interviews like this.

[Anonymous No.13740452]

>>13739972
baste

[Anonymous No.13740569]

PhD candidate in statistics here. OP's question is nonsense, I promise.

The way autists think quant desk interviews go is priceless. I imagine OP concocted this little story about being sociopath CEO in his head one night and came to /biz/ to play big trader man. Too cute

[Anonymous No.13740636]

>>13733814
Previous flips have zero effect on future flips. If you flip 100 times and they are all heads you should question if the coin is weighted or if the environment is affecting the flip like magnets under the table or the table being magnatic but if you have a completely fair coin in a fair environment, every independant flip will be 50/50 regardless of previous flips.

[Anonymous No.13740707]

>>13738823
This guy gets it. It isn't "clever" to assume some dumb shit like a weighted coin. What a dumb shit

[Anonymous No.13740719]

>>13740089
Look at this website
https://www.expunctis.com/2019/03/07/Not-so-random.html

And imagine the left or right key presses are the buys and sells of a trader. Human are predictable, the stock market isn't random and we have proofs of that, simply because stock prices have properties that shouldn't occur in a Brownian motion (leverage effect, time asymmetry, ...).

We want to make you believe you can't predict the market, while we crunches TB of data to modelise the market's participants behavior.

Have a good life.

[Anonymous No.13740725]

>>13733814
50/50 to both

[Anonymous No.13740731]

>>13740636
Once again, that's not how probability works.

[Anonymous No.13740754]

>>13733853
I'd laugh in your face and then get up and leave. Muttering on my way out "haha, the fuck said 'only looks ordinary'... hahaha, what a dumb fuck..."

[Anonymous No.13740772]

>>13733999
>the point is that the coin doesn't have a 50/50 chance of going heads/tails
fuck your trips. it literally does. each flip has a 50/50 chance of being heads or tails. each flip is an independent event.

[Anonymous No.13740780]

>>13740731
it is unless you're figuring in the probability of multiple coin flips. During any individual flip the probability is still only 50/50.

[Anonymous No.13740787]

>>13738706
>priority
>thinking there is a cosmic force that alters outcomes to enforce human misconceptions regarding probability
these are the people posting on /biz/

[Anonymous No.13740797]

>>13740772
This anon gets it

[Anonymous No.13740806]

>>13740731
Wow. American?

[Anonymous No.13740827]

>>13740806
Hey tbf, America is a big place! We're not all retarded mouth breathing faggots like that anon. Some of us had a decent education.

[Anonymous No.13740843]

>>13740827
^this

[Anonymous No.13740899]

>>13740780
You can't look at "individual flips" though when performing multiple flips. True that an individual isolated flip is 50/50, but when you have prior information, you can't ignore it in probability calculation. So your chance of heads again goes down by 1/(2^n) for every roll.

>>13740806
Stop being a retard, this is like high school probability tier

[Anonymous No.13741064]

>>13740899
>i feel that this sequence of indeend t events is increasingly improbable, so god or an angel or some other unknowable cosmic force will alter the outcome of the next independent event so as to conform said sequence of independent events to something I deem reasonable
This is your brain on American public schools.

[Anonymous No.13741111]

>>13741064
What the fuck are you on about?

[Anonymous No.13741198]

>>13741111
You are dangerously retarded, that’s all I’m saying. American public schools are a disaster.

[Anonymous No.13741265]

>>13741198
I just reread it and I still don't know what the fuck you are on about. Do they not teach europoors basic probability?
Improbable != impossible you mong. If somebody asked you to bed five bucks on the 101th coin trial, and you KNEW it wasn't rigged, you would bet tails. Because the probability that the 101th trial is heads after 100 heads is like 1/10^30 or something in that ballpark. If probability didn't work like this, then you would just pick whatever because "well 50/50"

Go read the proof on the monty hall problem

[Anonymous No.13741325]

>>13733853
Hidden semantics. Neck yourself moron.

[Anonymous No.13741347]

>>13741265
Coin flipping is independent each time. The Monty Hall problem is not - the outcome is already fixed, and you are merely given more info about it. The analog to coinflipping would be shuffling goat location, opening, then closing the door and reshuffling the goat location before guessing again.

You are seriously very dumb, sorry.

[Anonymous No.13741388]

>>13741347
Are you mentally retarded? What country. Gimme a country. This isn't about the individual outcomes, when you have previous results, it impacts your probability.

The intuition is obvious, too. Why is flipping 100 coins and only getting heads weird? Because you EXPECT to get tails eventually if the probability is 50/50. And the odds of getting 100 heads is EXTREMELY low.

I'm begging you, just Google coin flipping probability. It's all over basic Internet pages.

[Anonymous No.13741404]

>>13733814
>I take an ordinary-looking coin out of my pocket. I flip it 3 times and it is always heads. What is the chance that the next flip is also heads?
6.25%

[Anonymous No.13741446]

>>13737597

[Anonymous No.13741453]

>>13741388
Every time you flip your chance for that flip is 50/50. Period. The coin is not influenced by some magic force to land on tails merely because you flipped heads a million times in a row before. Now back to your Bud Light.

[Anonymous No.13741469]

>>13741453
Yes retard. Now take the next step and think about 100 coin flips and get back to me.

[Anonymous No.13741561]

I'm amazed that some people ITT are even able to operate a computer and get online.

[Anonymous No.13741602]

>>13741561
Probability is the easiest thing to troll people on because nobody took any math beyond high school on the Internet.

Bertrands box is a fun one, guaranteed 300 replies on any board