I've reproduced 130 research papers about “predicting the stock market”
This is unsurprising. P likely is not equivalent to NP [0], and predicting the market is NP-hard [1]. It's nice to see empirical work in the field, though, and especially nice to see reproductions of published papers.<p>[0] <a href="https://www.scottaaronson.com/papers/pnp.pdf" rel="nofollow">https://www.scottaaronson.com/papers/pnp.pdf</a><p>[1] <a href="https://arxiv.org/abs/1002.2284" rel="nofollow">https://arxiv.org/abs/1002.2284</a><p>Edit for downvoters and repliers: If enough market participants are irrational, then it can still be possible for people to predict <i>other people</i>, instead of the market, and make money that way.<p>NP-hardness indeed doesn't rule out heuristic approaches, but experience with 3-SAT and other NP-complete problems suggest that there will be arbitrarily bad times, and that in those times, the amount of loss can be exponential in the length of time that the heuristic poorly predicts the market.