Hedge fund posts huge gain in January

Cantab Capital Partners

Cantab Capital Partners' main hedge fund gained 13.4 percent over January, instantly making it a top performer for 2015 and continuing a hot streak for so-called quant managers who use computer algorithms to invest.

The Cantab fund has hundreds of positions at once, but several economic events helped produce the largest gains, according to a private letter to clients obtained by CNBC.com.

The European Central Bank's announcement in January of a fresh economic stimulus program, for example, supported Cantab's long position in German bunds and a short on the euro. The Bank of Canada cutting interest rates also benefited a short position on the Canadian dollar and long Canadian government bond bets. Cantab also made money on commodities by shorting oil-related securities and base metals like copper.