On most workday mornings, my e-mail contains a newsletter 
promising "unbiased opinion" -- an editorial oxymoron whose intent is probably to deny the presence of commercial advocacy or personal bigotry in the materials presented.
We tend to think of bias as necessarily negative, but in fact a bias is just a predisposition to believe or disbelieve new information about someone or something. Positive bias is rarely recognized. If something we read is consistent with our own beliefs, we don't typically see it as biased, even if those who hold contrary opinions do.
I have a friend, for example, whose ardent embrace of all things Microsoft (Nasdaq: MSFT) 
has been completely undampened by 15 years of lost files, forced upgrades, untimely crashes and DLL hell. To him, my enthusiasm for Mac OS and Unix is bigotry, while I consider his inability to value experience over peer pressure a perfect illustration of bias in operation.
Reprising Festinger
Ultimately, this is a question of values: He values the social lubrication that comes from shared pain over technology; I don't. Unfortunately, this spills over into how we respond to opportunities to gain new information or insights. Generally, we seek out and accept information consistent with our views while rejecting, often on the basis of source rather than content, the reliability and interest of contrary information.
For example, let's say my friend and I both saw an article starting with the following sentence: "Our next-generation OS will be the most secure ever released for commercial use." Whether either of us would continue reading the article would depend on whether the speaker represented Microsoft or the BSD developer community.
My friend's decision would be wrong, of course. After all, Longhorn is what you'd expect from an attempt to reinvent Pick by hacking the Jet drivers on the basis of a BeOS brochure, but that's not the point. The point is that it's impossible to be sure that what you choose to know hasn't been heavily influenced by preexisting bias.
In other words, the phrase "I am what I read" has the corollary of "I read what I am," and correspondingly, neither you nor I can ever really know if our opinions are predominantly attributable to a selection bias in what we read.
Troubling Indeed
I got my first Sun workstation, a 3/160 with a 20-inch screen running SunView, in 1985 and have upgraded to newer Sun gear roughly every four to five years since. It's fair to suspect, therefore, that I might be a little biased in Sun's favor.
That means I was also correspondingly upset when a recent anonymous Associated Press story started with the words "Troubled Computer Maker Sun MicroSystems..." and ended with the usual nonsense about Solaris/SPARC being unable to compete with "industry standard" servers using Linux.
MCI is "troubled" -- it's in bankruptcy. Tyco is "troubled" -- its former CEO is charged with stealing US$600 million from the company's shareholders. Martha Stewart is "troubled." But Sun just made an extremely conservative accounting change having no effect on its business, its cash position or its earnings potential. So why did this particular writer unleash such highly prejudicial language without troubling with facts?
Was it bias, incompetence, advocacy, market manipulation or just plain malice? I wish I knew, but in truth, I'm not even sure how much of my own angry response reflects bias rather than knowledge.
Mirror, Mirror on the Wall
On the other hand, I'm quite sure the people who send me flame-mail every time I comment on the disgraceful cost and performance offered by IBM's (NYSE: IBM) mainframe Linux have it wrong.
In my unbiased opinion, people who use company gear and company time to send me stuff like the following e-mail , with no less than eight follow-up messages, have personality problems that go well beyond bias:
Paul, I researched your article. I've determined that you made up the research and nothing in the article has any truth. I couldn't find any of the intermediary evidence you suggest. It was a slam dunk to find the lies. Did you have a motive for writing this article?
Then again, maybe not. After all, I might do the same if I had that anonymous Associated Press writer's e-mail address.
Paul Murphy, a LinuxInsider columnist, wrote and published The Unix Guide to Defenestration. Murphy is a 20-year veteran of the IT consulting industry, specializing in Unix and Unix-related management issues.
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