Informational Cascade and the Digital Hordes

One of many issues that you face when dealing with the Digital Horde is Informational Cascade. Put simply; when someone states a fact or answers a question, those that follow can skew their answers towards that answer even though they originally had a different answer.

This is less true of expressions of opinion, but it can play a part.

There's an interesting example of informational cascade in this article: Diet and Fat: A Severe Case of Mistaken Consensus which explains how medicine was almost hoodwinked into believing that fatty foods shorten lifespan based on dubious assumptions and data.

While the article - and the example - are interesting, the following statistic is the takeaway:

[...] groups are surprisingly prone to reach mistaken conclusions even when most of the people started out knowing better, according to the economists Sushil Bikhchandani, David Hirshleifer and Ivo Welch. If, say, 60 percent of a group’s members have been given information pointing them to the right answer (while the rest have information pointing to the wrong answer), there is still about a one-in-three chance that the group will cascade to a mistaken consensus.

Perhaps my favorite example of Informational Cascade is highlighted in a clever letter written to the radio show Car Talk that pointed out how the hosts had engaged in mad speculation about a topic that they new nothing about:

I am writing to offer profound thanks to you for resolving an important philosophical question that has been heatedly debated for the last twenty years. [...] Do two people who don't know what they are talking about know more or less than one person who doesn't know what he's talking about?
...
One person will only go so far out on a limb in his construction of deeply hypothetical structures, and will often end with a shrug or a raising of hands to indicate the dismissability of his particular take on a subject. With two people, the intricacies, the gives and takes, the wherefores and why-nots, can become a veritable pas-de-deux of breathtaking speculation, interwoven in such a way that apologies or gestures of doubt are rendered unnecessary.

In the final analysis, Informational Cascade confirms that results are more accurate if the respondents don't know how previous respondents have answered a question.