Qualitative research resides at the touchy-feely end of the research spectrum. It is an open-ended method of acquiring information about the consumers' product requirements (what they want) or product perceptions (what they think of what you've got). While the variations are limitless, this type of research typically takes the form of focus groups, user testing, or email feedback.

Qualitative methods can be useful in all stages of development and tend to be quite popular. These methods are very tangible to marketers and developers because they most often involve sitting a group of people down in a room and actually talking with them about the issues at hand. If an interviewee says something of particular interest during a focus group, the interviewer can probe deeper into the topic, uncovering information that might never be gleaned from a dozen brainstorming meetings. Similarly, if users do something unexpected during a usability test, the interviewer can ask what the heck they hoped to accomplish by, say, constantly viewing source and then endlessly clicking on the tags.

While qualitative data is very accessible and often leads to never-before-considered results, it falls short in the realm of reliability. Qualitative research tends to be highly biased, and it is essential to interpret results while keeping in mind the context in which they were gathered. Even so, all research is biased in one way or another. The important thing to remember while conducting research is to examine biased data; don't dismiss it out of hand. It's smart to try to understand the nature of the bias you introduce into your research and interpret your findings accordingly.

A brief example: You ask one of your engineering buddies to review a mock-up of your new Web site, which is targeted at college students. He pokes around on the site, and sends you back an email message to tell you he loves it (no surprise - he's still has your mountain bike, which he borrowed four months ago), but has a couple of comments:

1. He has difficulty making out the text on navigation buttons. 2. He thinks you should add a section to the site that lists "good studying places in your neighborhood."

Now, your buddy's pushing 30, and he didn't even graduate from college (he was hired straight off a BBS into some company that is now worth slightly more than most developing nations). So he obviously doesn't represent your typical college student. Consequently, in terms of being representative of your average college consumer, his feedback is probably pretty biased.

Should you ignore his comments entirely?

Not necessarily. You need to determine what differentiates your buddy from a college student and ignore any findings that might be influenced by these factors. Though your buddy has been staring at computer screens for 10 hours a day since well before amber screens were the rage, you've played laser tag with him and know his vision is just fine. So when he tells you the text on the navigation buttons is too small to read, you can be pretty confident that a college student would have the same complaint.

What about your buddy's suggestion that you incorporate a section on local study hot spots into your site? Well, you know he has never studied a day in his life, so you probably don't want to implement his idea immediately. That's not to say it's a bad suggestion. It just means that you should probably talk to some college students about the value of this feature before spending late nights at local cafes - to see how long you can nurse a cup of coffee before you and your pile of books get kicked out.