Deliberate Bias

Deliberate Bias

Author: Jonathan Osters

This lesson will explain deliberate bias.

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Video Transcription

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This tutorial is going to teach you about deliberate bias. Now deliberate bias is what it sounds like. It's bias that's done on purpose.

Now this doesn't happen very often. Deliberate bias can occur when there's a conflict of interest between the people performing research and the people funding, or benefiting, from that research.

So, for example, suppose a drug company funds a study to determine if it's latest drug is effective. The researchers stand to gain a lot of money and prestige for having tested the drug in proven it effective. So they might not be the best choice to test the drug.

Or an environmental research group is hired by a real estate developer to investigate the effects of a new building. Now the thing is they might get another contract with that developer if the results are favorable. And they might think, well if we don't give them a favorable interpretation here then someone else will. And they'll get the next contract. And so the environmental research group stands to gain by being hired by the developer again on another project. So there's a little bit of a conflict of interest. And they can maybe pull some punches or not make it seem like it's quite as bad.

Typically deliberate bias is motivated by an interest unrelated to the integrity of whatever your researching. Most research is done with integrity. But when personal prestige, advancement of some ideology, or money get in the way then it's harder to prove that your intentions are pure.

Sometimes this happens fairly often in politics. People will call with a poll and put into their survey a leading question in order to cause the person to lean one way or the other or to put an idea in someone's head.

So, for example, a questionnaire sponsored by the makers of drug B, which are right here, might say if you knew drug A was linked to cancer would you be more likely to choose B, less likely to choose B, or equally likely to choose B. Well, I mean obviously, it would make you more likely to choose B.

And now look at what they've done. They've put it in the person's mind the drug A is linked to cancer. Did they ever explicitly say that? No, they said if it was linked to cancer. But that doesn't make any difference. They've placed the association in the participant's mind. And subconsciously they're beginning to steer them away from drug A and towards drug B.

When this is done in politics it's called push polling. And it's very highly suspect.

And then finally there's unintentional bias. Unintentional bias occurs when there is simply an error in the design of the study. So unintentional bias might be response bias due to wording of questions or people feeling like they have to lie. Or selection bias, which has to do with how the sample got selected where people got not covered representively. These are simply errors they're not intentional.

And so to recap, most of the time this isn't an issue. Most of the time deliberate bias is not something that we need to think about. Most of the time research is done with integrity. And when bias occurs it was on accident. However sometimes people with personal interests, like the advancement of an ideology or financial gain, they can steer results towards outcomes that are favorable to them. And that's called deliberate bias. Good luck. And we'll see you next time.

  • Deliberate Bias

    The purposeful misrepresentation of data for the purpose of advancing an agenda.

  • Unintentional Bias

    Bias that is not purposeful. It exists because of errors in the design of the study.