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Numerai – A hedge fund built by a global community of anonymous data scientists

numer.ai

31–40 of 120 posts

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#32

"It's just a pure math problem. It's like a math competition. You don't need to know anything about finance, you don't know anything about hedge funds... you don't even have to speak English..." This is not a pure math problem. Eventually the outcome of all these models and predictions affects the stock prices and - if it becomes as successful as you hope - the economy as a whole. And the physical world: people, anim…

We didn't start the fire It was always burning Since the world's been turning

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#33
post #7

The training set just has anonymized features. Data scientists generally would like to know the nature of the data they are working with. Does the site at any point give access to the labeled featured?

No, at least thus far you know nothing about what the features represent. They are just labeled feature1 through feature21.

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#34

Couldn't I make thousands of fake accounts and submit thousands of slightly different models. Then after a while I could push one or two of my stocks higher in my models artificially. If you represented a large enough % of the "data scientists" in this hedge fund you could make it look like your stock is "definitely" work investment. After they invest in your company, you could take off to the hills. Hell, you don't…

You don't know anything about the dataset they give you so this wouldn't really work. Its not like they tell you which stocks each row in the dataset correspond to. On top of this you know nothing about the features.

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#35
tldr - novel encryption method allows for sharing of data sets and better machine learning models. Aggregation of models into a portfolio offered as a hedge fund.

Found this company interesting, read a bunch of blogs from them and tweetstormed: https://twitter.com/Royal_Arse/status/787725301908242432

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#36
Things I do not understand:

* How does a logloss relate to earnings?

* They only receive predictions based on old data (by definition) and not the models, how do they just the predictions them to make trading decisions?

* How can I invest in this hedge fund?

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#37
Their dataset reeks of startup hustling.

I just downloaded the training set [1] and plotted some of its descriptive statistics [2]. It looks that all features are uniform distributions and the response variable is Bernoulli coin-flipping. In layman's terms, you can't really come up with a good predictive model with this training set.

I give them the benefit of the doubt that they wanted to have something in place to push the website live, but I cannot imagine any serious data scientist not noticing this.

[1] http://datasets.numer.ai/57feb95/numerai_training_data.csv

[2] https://cl.ly/051G3Y2Z2O0W

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#38
post #37

Their dataset reeks of startup hustling. I just downloaded the training set [1] and plotted some of its descriptive statistics [2]. It looks that all features are uniform distributions and the response variable is Bernoulli coin-flipping. In layman's terms, you can't really come up with a good predictive model with this training set. I give them the benefit of the doubt that they wanted to have something in place to…

The features are all encrypted using homomorphic encryption, which ends up mapping the overall distribuiton uniformly onto [0, 1]. If you play with the dataset, though, you'll find there are some significant correlations between the different features and you can make a model that does substantially better than chance.

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#39
I don't see how Numerai can avoid the multiple comparisons problem [0]. If people submit thousands of random models, then some subset of them will do a fantastic job in predicting prices in historical simulations but do poorly under real market conditions. As long as the models are black boxes, there's likely no good way to distinguish them from noise.

[0] https://en.wikipedia.org/wiki/Multiple_comparisons_problem

Re: Numerai – A hedge fund built by a global community of anonymous data scientists

#40
post #22

Couldn't I make thousands of fake accounts and submit thousands of slightly different models. Then after a while I could push one or two of my stocks higher in my models artificially. If you represented a large enough % of the "data scientists" in this hedge fund you could make it look like your stock is "definitely" work investment. After they invest in your company, you could take off to the hills. Hell, you don't…

You don't even need to push one or two stocks higher. With thousands of fake accounts you could just pick a different stock for each account at random. Certainly a few of those stocks will turn in huge returns. Collect your Bitcoin reward from Numerai. Repeat. Maybe they have some way of preventing people from gaming the system that way?

The thing is, with the data no one knows what each row represents, or even what the features are or what they're predicting is. Each submission has 30,000 predictions, so you would need to have an unreasonably good random guess to get anywhere near the top of the leaderboard.
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