Adding on to what James said, here are some other resources to help you code the algo:
Buy all stocks in Dow Jones, Nasdaq 100, and S&P 500
Your algo is limited to trading 500 stocks, but you can mimic an index using fundamental data: https://www.quantopian.com/posts/simulating-s-and-p-500-russel-1000-russell-3000-in-research
at least a 100,000,000 Market cap, a 3.5 EPS, and P/E ratio less than 40
You'll want to use fundamental data to make this query. Here is an example.
The beta must be greater than 0.85
This is up to your algorithm design :)
Reweigh the stocks each week by their market cap
You can use order_target_percent to maintain the target weights.
if the stock goes down 5%, or goes up 10%, sell all of it, and do not include the stock in the future till one month since the selling date has passed.
Track the stock's price versus your fill price using the data object. And use schedule_function to set the days/times when to trade.
Once you're comfortable with the code and developing the guts of the algo, keep these algo writing tips in mind.
Cheers,
Alisa
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