"A slow, steady positive return makes for a great diversifier to much more volatile equity returns."

As a result, these researchers say, nothing can be learned about gold's role as a portfolio diversifier by studying that period.

In a science of unifiers, Dyson prides himself as a diversifier.

Diversifying Waste Management has been the most aggressive diversifier.

Analysts do not advise going whole hog into commodities because they are mainly a portfolio diversifier.

Accordingly, GTAA should be a good diversifier, particularly within an alpha portfolio.

Talk about a diversifier: "Ten percent in that would have salvaged the whole portfolio," Mr. Bingham said.

Meanwhile, Mark Harris of New Star said gold shares continued to look cheap and remained a decent portfolio diversifier.

Investments that are not highly correlated to the market are useful as a portfolio diversifier and may reduce overall portfolio volatility.

Because REIT's typically have a low correlation to stocks and bonds - in other words, they tend not to move in tandem - they are regarded as a good portfolio diversifier.

But, more important, commercial real estate in general has evolved into an accepted asset class among investors as well as an excellent portfolio diversifier, said John J. Kriz, the managing director of real estate finance for Moody's Investors Service.