Coin Flip

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ppnewbie
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Coin Flip

Post by ppnewbie » Wed Apr 01, 2020 12:19 pm

Does anyone know a volatile force in the market that is:

As close to random as possible
I could make a big bet on that I would double money on if the bet went my way or lose half (preferably not 100 percent) if the bet went the wrong way.
The random force occurred as much as possible - preferably around once a day

I am working on strange speculative trading strategy. Thanks!
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Tortoise
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Re: Coin Flip

Post by Tortoise » Wed Apr 01, 2020 12:25 pm

If the probability of winning is 50%, you double your money if you win, and you only lose half of your money if you lose, isn't the expected return on the bet 25%? (0.5 * 0.5 + 0.5 * 2 = 1.25)

Those are damn good odds. I want in! ;)
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Mark Leavy
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Re: Coin Flip

Post by Mark Leavy » Wed Apr 01, 2020 12:35 pm

ppnewbie wrote:
Wed Apr 01, 2020 12:19 pm
Does anyone know a volatile force in the market that is:

As close to random as possible
I could make a big bet on that I would double money on if the bet went my way or lose half (preferably not 100 percent) if the bet went the wrong way.
The random force occurred as much as possible - preferably around once a day

I am working on strange speculative trading strategy. Thanks!
Oh come on. Did you just read about Shannon's Daemon?
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Mark Leavy
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Re: Coin Flip

Post by Mark Leavy » Wed Apr 01, 2020 12:44 pm

If you are going to pursue this path (which I assure you doesn't exist for the ordinary investor), you can generalize the 50/50 odds to any other odds ratio using the Kelly Criterion. Or, preferably, fractional Kelly.

A fantastic read is "Fortune's Formula".

Or read up on the early history of Shannon and Thorpe. They were some crazy fun dudes.
Thorpe still posts occasionally on one of the Quant forums that I follow.
ppnewbie
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Re: Coin Flip

Post by ppnewbie » Wed Apr 01, 2020 12:44 pm

Probably. I tried it with some code and the results were very interesting. Do you have any idea on how to try this in the real world?
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shekels
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Re: Coin Flip

Post by shekels » Wed Apr 01, 2020 12:47 pm

I know this may not Help.
But Bet on the Bankers. aka the Fed.
Because in this market it's Head I win Tails you Lose.
¯\_(ツ)_/¯
ppnewbie
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Re: Coin Flip

Post by ppnewbie » Wed Apr 01, 2020 12:57 pm

Perfect thanks. During the quarantine, I can learn about the Kelly Criterion. Thanks!
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Mark Leavy
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Re: Coin Flip

Post by Mark Leavy » Wed Apr 01, 2020 12:58 pm

Actually, I take back the "doesn't exist" comment earlier. The Shannon's demon effect is one of the explanations for the rebalancing benefit in a diversified portfolio. Random stock movement do sometimes "half and/or double". (Or some other percentage and it's inverse).

If you wanted to implement your strategy more practically... You could place a daily bet on some random stock that might go up or down and then close your position with limit orders at either (say) 90% or 111% (1.0/0.9). You would have to use Kelly to pick your bet size to avoid ruin.

Good luck!
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Re: Coin Flip

Post by ppnewbie » Wed Apr 01, 2020 1:18 pm

I was thinking that the PP is essentially a form of this strategy. LTT and Stocks are fifty percent risk on (the coin flip) and cash and gold are fifty percent risk off portion of the bet that rebalances. It's just the time period is to slow. I need to go through kbg's "inspired leveraged portfolio" thread.
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Tortoise
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Re: Coin Flip

Post by Tortoise » Wed Apr 01, 2020 1:20 pm

Not to discourage learning and experimentation with using the Kelly criterion in options trading, but aren’t any expected gains already baked into the option prices (on average)? Otherwise it seems like hedge funds and big quant groups could swoop in and make a killing using very simple math.
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Re: Coin Flip

Post by ppnewbie » Wed Apr 01, 2020 1:51 pm

I need a free lunch! ;)
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Smith1776
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Re: Coin Flip

Post by Smith1776 » Wed Apr 01, 2020 6:59 pm

https://www.reddit.com/r/wallstreetbets/

Peruse Wall Street Bets at your leisure, and start putting down money on options.

People s#$t on that place, but there's a occasionally some method to the madness there.
I still find the James Rickards portfolio fascinating.
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Mark Leavy
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Re: Coin Flip

Post by Mark Leavy » Wed Apr 01, 2020 6:59 pm

Tortoise wrote:
Wed Apr 01, 2020 1:20 pm
Not to discourage learning and experimentation with using the Kelly criterion in options trading, but aren’t any expected gains already baked into the option prices (on average)? Otherwise it seems like hedge funds and big quant groups could swoop in and make a killing using very simple math.
Whatever you do, ppnewbie, don't try this scheme with options. The trading cost, slippage, spread and blowing by your limits would destroy any chance at all of coming out ahead. It's a huge mistake to not count those into your modeling program.

If I were going to give this a shot, I would use some highly liquid, highly volatile ETF that you could trade for free. Maybe one of KBG's triple leveraged Nasdaq ETF's or something like that. One more issue that you would need to factor in: The distribution of wins/losses are guaranteed not to be gaussian. So don't use a random number generator for your simulation. You would be surprised how quickly you can go broke if you assume a normal distribution. Model this with historical tick by tick prices if you can get them.

Should be a fun experiment. If you're careful, it won't be completely stupid and you might do okay.

Keep us updated if you jump in.
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Mark Leavy
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Re: Coin Flip

Post by Mark Leavy » Wed Apr 01, 2020 8:59 pm

I just did a quick look at TQQQ to see if that would work. It has the volatility you need on a daily basis, but the gaps up and down between the closing and opening prices are huge. You would gap past your exit limits a large portion of the time. Those slips would make this scheme way too risky to consider. Picking up pennies in front of a steam roller.

You would need something that traded round the clock so that you could reliably close each trade at your target percentages.
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Re: Coin Flip

Post by InsuranceGuy » Thu Apr 02, 2020 1:11 am

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Last edited by InsuranceGuy on Mon Mar 08, 2021 5:42 pm, edited 1 time in total.
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Re: Coin Flip

Post by ppnewbie » Thu Apr 02, 2020 2:21 pm

One more issue that you would need to factor in: The distribution of wins/losses are guaranteed not to be gaussian. So don't use a random number generator for your simulation. You would be surprised how quickly you can go broke if you assume a normal distribution. Model this with historical tick by tick prices if you can get them.

Good point Mark!
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Re: Coin Flip

Post by ppnewbie » Thu Apr 02, 2020 2:23 pm

InsuranceGuy wrote:
Thu Apr 02, 2020 1:11 am
OTM options on SPY/SPX should be able to be calibrated to 50/50.
Thanks for the suggestion.
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Mark Leavy
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Re: Coin Flip

Post by Mark Leavy » Sun Apr 05, 2020 6:26 pm

Just in case you are still playing with this idea, here's the equations for the mean return, rebalance return (volatility harvesting return), and total return for two assets:. Which is what your scenario is.
(stolen from somewhere on reddit)

I tried this with a handful of numbers representing corner cases and it seemed to come up with the results I would have expected - including the right answer for Shannon's lecture example. So... it looks good on first blush.

Code: Select all

mean return = w1*r1 + w2*r2

rebalance return = w1*w2*[v1*v2*(1-c) + 0.5*(v1-v2)^2]

total return = mean return + rebalance return 

Where,
w1 = allocation to asset 1
w2 = allocation to asset 2 (w1+w2=1)
r1, r2 = expected return of asset 1 and 2
v1, v2 = volatility of asset 1 and 2
c = correlation coefficient

Applying that to your original scenario. (Shannon's example). Each wager is 50% of your net worth and the return is either a 50% loss or a 100% gain. And you make that wager once each day...

This is modeled as one asset being cash (0 expected return, 0 volatility) and the other asset is some speculative, non trending, product that goes up or down randomly and you get out daily at double or half your wager. (0 expected return, 1/sqrt(2) variance).
ShannonsDaemon.png
ShannonsDaemon.png (56.48 KiB) Viewed 5197 times
Again, of note, this only works if the returns are somewhat normally distributed. There is no equation for it, but if you run a monte carlo analysis this scheme lags behind buy-and-hold on a product that is trending upward and it loses more than buy-and-hold on a market that is trending downward. So... to make this work better than buy-and-hold (in addition to all of the other real-world issues) you need to use some underlying asset with "random" movements that don't result in any long term trends.

Again, best of luck!
Mark
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Re: Coin Flip

Post by senecaaa » Mon Apr 06, 2020 1:44 pm

Mark Leavy wrote:
Wed Apr 01, 2020 8:59 pm
You would need something that traded round the clock so that you could reliably close each trade at your target percentages.
bitcoin?
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Mark Leavy
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Re: Coin Flip

Post by Mark Leavy » Mon Apr 06, 2020 1:52 pm

senecaaa wrote:
Mon Apr 06, 2020 1:44 pm
Mark Leavy wrote:
Wed Apr 01, 2020 8:59 pm
You would need something that traded round the clock so that you could reliably close each trade at your target percentages.
bitcoin?
No. The spread is too large.
Futures.
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