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Using a Keras Long Short-Term Memory Model to Predict Stock Prices

heartbeat.fritz.ai

11–20 of 178 posts

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#11
post #5
post #2

Pretty underwhelming. From the very limited experiment demonstrated, the LSTM seems to be playing catch up rather than actually predicting trends.

You say that because the prediction line lags the price line? That’s not playing catch up, if the prediction was made at time 0.

It doesn't specifically say as far as I can see, but I'm highly doubtful that the prediction was made at time 0 (i.e. with no seed data). That would literally be a lucky guess.

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#12
I wonder if someone could comment on how AI is used at big investment banks? I assume its much more than technical analysis (like this model). I imagine that NLP might be helpful for quickly ingesting a news feed and then making buy/sell decisions based on the news in less time than humans can read and react?

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#13
post #12

I wonder if someone could comment on how AI is used at big investment banks? I assume its much more than technical analysis (like this model). I imagine that NLP might be helpful for quickly ingesting a news feed and then making buy/sell decisions based on the news in less time than humans can read and react?

As you mentioned, one way is to quickly ingest earnings announcements from press wires/company websites. As soon as the earnings report hits the wire, they want to immediately known how big a miss/beat was it, and whether they should immediately dump it or buy more.

Other examples include analyzing the words/sentiments in earning calls, to see if certain words indicate a bearish or bullish signal. For example if a CEO mentions the word "headwinds", does that historically lead to a much better quarter next time?

Some other companies do analysis with public/private data. For example, you can use a weather dataset to calculate the average temperature for all cities where there are restaurants owned by Cheesecake Factory in a quarter, and see if it will negatively or positively impact sales.

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#15
Signal/noise on the market is extremely low, and determining whether you’re predicting something or just data snooping your way to a function that looks like it predicts something is a serious competitive advantage in itself (... because all you need then is novel functions to try).

Working out a function that passes a split test is inevitable and easy tbh. That function then making money is highly unlikely. This is especially true if your data sources are public.

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#16
post #3

The problem with these types of systems are it's difficult to do backtesting on a single continuous data stream... I write about that here: https://blog.projectpiglet.com/2018/01/perils-of-backtesting... I recommend doing something similar to the original post. Neural networks tend to produce valid looking output for a stock price easily, a random walk does too. You have to find correlations, causations, and then rev…

> I wrote my own financial advisor (not directly utilizing deep learning, that functions relatively well)

I do not see enough data to backup the claims of how well it works. And if you can't provide that - what good is it as a tool?

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#17
Well, I'm only on mobile. But the problem with stock prices is often that you don't have good data, unless you are working for the big four or whatever. And even then, they are apparently still working on integrating external data in real time.

Imagine having the whole Twitter stream, maybe categorized by some network in an automatic way.

Also prequential evaluation.

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#18

I preliminarily did the same thing as in this article a while back (with crypto data, since it's easily accessible), just as a way to learn keras. Somehow my network always learned to output a delay of the input no matter how hard I tried to shape it. I've searched through literature briefly and some examples. Some blog posts even claimed they had good time series prediction when I clearly saw they were having the sa…

You are not alone. With time series that is the easiest solution for any model. That is why you need a lot of work creating your datasets and the experiment setup with time series. To avoid the easy solution and obtain something useful.

Re: Using a Keras Long Short-Term Memory Model to Predict Stock Prices

#19
post #2

Pretty underwhelming. From the very limited experiment demonstrated, the LSTM seems to be playing catch up rather than actually predicting trends.

I noticed this as well.

Many data science thought pieces don't quantify the results, and it's suspicious that they're not included in detail (typically, the R^2 of a simple stock market prediction model is super low, making it impractical putting actual money on the line as it's barely better than guessing randomly: https://twitter.com/minimaxir/status/1021885939361042432 )

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