Comment by AmericanChopper

You can observe it by counting the contractors in any company that has salary bands, or transparency, or any other similar system. Very few high performing employees are prepared to accept that their remuneration is being constrained to prevent the lower performing employees from getting jealous. They are strongly incentivised to either leave or become contractors, increasing their remuneration even more. Only the average performing and under performing employees readily accept such an arrangement, because they are either unaffected by it, or benefit from it. You don’t need to do a study to figure out that people avoid things that are detrimental to their own interests.