We've recently been working on a wiki project to stem the tide of front-page turnover on Quantopian.com and the quant blogosphere in general. It's still pre-launch, but you can already get a glimpse at http://quantapolis.com.
The wiki has a collection of links to some of the best algorithms on Quantopian. It's amazing to see what you all build in open-source, and we're trying to give back. We'll provide a series bare-bones examples of quantitative trading strategies for illustration purposes and ease of learning. This comes right to the tune of the awesome algorithms, lectures, tutorials and resources published by so many other members of the community recently.
This algorithm demonstrates a basic long-short value strategy. The strategy manages a beta-neutral, concentrated portfolio of US large-cap stocks on NYSE and is based on the acquirers multiple (EV/EBITDA) with monthly rebalancing. We're trying to keep complexity to a minimum and only use a single ranking metric and the most important filters for smooth backtesting. Feel free to use it as template to hack it into something more sophisticated.
* Minimal complexity
* Simple ranking and allocation of stocks
* US large-cap stocks from fundamentals database
* Keeping the right price data available
* Avoiding obsolete stocks in the portfolio
* Avoiding short of momentum growth stocks