Index provider Solactive has thrown a curveball into the crowded smart beta ETF market, launching new indexes that claim to be "intuitive" rather than smart.

The new Solactive intuitive beta indices will place "gut feeling" and "intuition" at the heart of their investment strategies, and reject the use of academic factors and number crunching as used in smart beta indexes.

"We are [trying to] go beyond purely quantitative screens. [ETF] providers are seeking a storyline behind the strategies they deploy in their products. With this in mind, intuitive beta promotes an approach based on intuitive and straightforward stories that should of course also translate into performance," said Timo Pfeiffer, Head of Research at Solactive.

One such index will be the Solactive Workforce Efficiency US Large Cap Index. It is based on the idea that there are two kinds of companies: capital intensive, like oil majors or banks, and labour intensive companies, like manufacturers.

Labour intensive companies require efficient workforces as labour productivity ultimately determines their success, Solactive claims. So indexing them as such makes intuitive sense.

Another index is the Solactive P/E Ratio US Large Cap Index, which is, as its name suggests, made up of companies measured by P/E ratio. Here again the idea is intuitive: when buying stocks investors should assess if a stock is fairly priced relative to its earnings.

Since undervalued stocks have historically tended to outperform those with high P/E ratios, the index targets stocks with the lowest P/E among US large caps.