There are a seemingly limitless number of “Exchange-Traded-Funds”(ETFs) available to individual investors. Whether you are looking to passively invest in a generic index like the S&P 500 or trying to take advantage of complex financial instruments and low cost leverage without needing to post margin, there is likely an ETF that can do what you need.

Solution: Create a tool that takes in the ticker of an ETF and returns its best guess as to what funds are similar and the characteristics of those funds.

This tool uses three metrics to determine how good of a replacement one fund is to another: The fit of the regression model, the leverage (Beta), and whether the fund moves inversely.

The fit: This is described by the R² of the daily price changes over a 30-day period.

The leverage: The Beta between the two funds. For a 1% change in the selected fund, what is the change of another fund?

The inverse: Whether the fund moves in the opposite direction as the selected fund. A fund that shorts the S&P 500 would move inverse to a fund that is long on the same index.