"Cheap" and "Free" Keywords: Not Always a Bargain

In an ongoing paid search advertising campaign, a large insurance company expressed interest in appending some of its keywords and keyword phrases with the words "cheap" and "free," as in "cheap health insurance" and "free insurance quote."

We tested these phrases and noticed some trends. Keywords and keyword phrases with solid conversion rates plummeted when "cheap" or "free" was appended onto them....A second phenomenon is the relationship between longer keyword phrases and higher conversion rate....The longer the keyword phrase, the higher the conversion rate.

Source: ClickZ