The peak-end rule

In reading The Paradox of Choice by Barry Schwartz, I came across one of those pieces of research that just keeps coming up in conversation, so I’ll post it here. The theory is known as “peak-end rule,” as expressed by psychologist Daniel Kahneman, describes the way that people remember events by the peak and the end of the experience. For instance, if I go to an amusement park, this heuristic says that I will remember my trip by the height of excitement and the way I felt when I left. The classic experiment showing this phenomenon is described by Mr. Schwartz:

Participants in a laboratory study were asked to listen to a pair of very loud, unpleasant noises played through their headphones. One noise lasted for eight seconds. The other lasted sixteen. The first eight seconds of the second noise were identical to the first noise, whereas the second eight seconds, while still loud and unpleasant, were not as loud. Later, the participants were told that they would have to listen to one of the noises again, but that they could choose which one. Clearly the second noise is worse–the unpleasantness lasted twice as long. Nonetheless, the overwhelming majority of people chose the second to be repeated.

These results are not limited to abstract, constructed experiences. Schwartz another experience with a little more real-world impact:

In the test, one group of patients had a standard colonoscopy. A second group had a standard colonoscopy plus. The “plus” was that after the actual examination was over, the doctor left the instrument in place for a short time… and it made a difference. It turned out that, over a five-year period after the exam, patients in the second group were more likely to comply with calls for follow-up colonoscopies than patients in the first group.

And of course, this example takes advantage of the colonsocopy rule: any research that deals with colonoscopies makes me uncomfortable, and therefore has more impact.

As I mentioned, since I discovered this rule, it keeps popping up in discussions I have been having. Having recently been on a vacation, it strikes me that this heuristic is of utmost importance in planning long events. It appears that the optimal planning for a vacation (or any event for that matter) would look something like this:

Peak-end rule

In the case of my vacation, the last high-point of my time in Europe was in Florence, followed by one brief day in Copenhagen. Not that there’s anything wrong with Denmark, but that day ends up coming up in more of my conversations than the rest of the trip because that is how memory works (that and blood jello is really, really disgusting). If you’re planning any trips soon, make sure to end on a high note, because you will be the one telling the stories.

Google news, meet spam

I’ve been a long-time user of Google news and news alerts. For certain topics, it’s the only way for me to stay informed, and the quality of their index has generally kept these updates to high-quality, on-topic news that matched some keywords. Over the past six months I have noticed a diminishing returns on the value of their search, especially in the case of alerts. While the amount of information has increased, the average quality has been diminishing. This decrease in relevance can be attributed to certain publications in their corpus:

Small publications: as more college newspapers, trade publications, and otherwise non-authoritative sources become primarily web-distributed, they have also started to overwhelm the news index. It’s rare these days to come across a story from a mass media publication.

PR announcements: some readers may remember a few months back when a 15-year old boy wrote a press release about how Google had hired him, and the entire affair turned out to be a hoax. Press releases seem to be a media that is not well policed, probably because they mainly come from

Blogs: The boundary between mass media and blogs has certainly blurred over the past few years, but the selection criteria for news indexes does not seem to follow any rules. Presumably the site maintainers take submissions to the site and decide based on internal editorial guidelines what to let in. Some of the blogs I have seen do not seem to make the cut, but maybe their inclusion of blog search into the interface suggests they are working on a better solution.

Syndication sites: a few news sources indexed by Google are actually sites that aggregate news from other sources. Try a search for any of your favorite spam keywords, such as “viagra,” you will find some surprising results. Spam?! It seemed absurd to me that spam could get into the news index, where every source was hand evaluated, but lo and behold, there are more than a few pages trying to sell viagra:

Google News vs. Viagra

What each of these examples points to is the need for a ranking mechanism that takes into account the reputation of the source. At last count, the US version of news is indexing over 10k sources, and as this bar gets lower, our collective trust in this site becomes more and more important. Unlike web search, which can be indexed and updated over the course of months, the news index has to be extremely fresh; for this reason, algorithms like PageRank cannot function properly. Attention indicators like, Digg or Newsvine might help, but each of these sources comes with an inherent bias that might not reflect the audience of Google News.

It seems much more likely that the sources of news will become the harbingers of trust. I am not advocating a return to old media, but the index could be built to reflect the current opinion of the web at large. If most sites trust the New York Times or the Washington Post as an authoritative host, so could a news search index. Andy Baio did an experiment around host ranking using Metafilter as a source, and the results from 1999 to 2006 are quite interesting: many sites appear out of nowhere (Youtube, Wikipedia) while others maintain rank over the years (New York Times, BBC). My guess is that standard news results run through this filter would provide a substantially better experience, especially for ranking results within a given news cluster. I guess we’ll see what the big G ends up doing to rectify the situation.

Amazon launches answers site

Askville LogoToday I received an invite to join a new community at Amazon called Askville:

You’re Invited!

As a valued Amazon customer, you’ve been specially picked to get an early look at a new website called Askville where you can ask any question on any topic and get real answers from real people. It’s new, and best of all, it’s free!

This site will compete with Yahoo! Answers and Microsoft Q&A in the free question-answering space except that it might be able to leverage the Amazon community of experts. For those that have not been following this area, these systems enable knowledge creation by allowing users ask questions that are then answered by other users in exchange for reputation within the system. The first success in this space was a startup in Korea named Naver that took control of the search market share in a very short period of time.

Amazon’s system is similar to all of its American counterparts, with its large fonts and friendly messaging (“ask.. answer.. meet.. play”), except for a few subtle distinctions:

  • Users are rewarded for asking questions as well as answering them
  • Questions are limited to 5 answers total
  • Best answers are chosen by the group of question asker and answerers, where the asker gets one more vote than the answerers

Probably the most significant change is the flow of the question/answering exchange. In Yahoo! Answers, and elsewhere, answers are shown publicly as they are received; in Askville, answers are hidden to the public until 5 answers have been received. Any discussion or clarification can happen in a public message board attached to the question. After 5 answers have been collected, the group of asker and answerers vote and the whole thing is made public.

Askville rewards users with “coins,” a virtual currency that will be redeemable in another community named Questville slated for release in early 2007.

The system has given me 25 invitations for other accounts. If you’re interested in trying out the system, shoot me an email.

Update: I apologize, but all of my invitations have been distributed! It seems like the invitations are spreading though, so look for one on a weblog near you…

Firefox 2 inline spell checker

I usually avoid the initial release candidates of open source software, but Firefox just released their beta 2 candidate about a month ago. I finally got around to installing it this week and I have to say it’s not that mind-blowing. They’ve added cleaner RSS support, more intelligent tabs, and a number of features that mimic former plugins.

While I was test-driving this new toy I went to some new ajax-spiffy application and was completely blown away by their inline spell checker, until I realized that it’s a standard feature on the new Firefox:

Inline spell checking: A new built-in spell checker enables users to quickly check the spelling of text entered into Web forms (like this one) without having to use a seperate application.

It’s essentially the same spell checker that has existed in more serious writing applications (word processors, email clients, etc.) for years, with red dotted lines under misspelled words and right-click action to suggest correct spellings. It appears that the authors of the above quote were using a previous version of Firefox as the word “separate” is spelled incorrectly. Of course I only noticed this because it has red dots below it in my browser.

Most good social software currently support spell checking, but the inline version it isn’t the sort of task that can be done in real-time by a web app. It makes perfect sense that this sort of functionality would migrate to the browser, given the amount of general text editing that is happening now on the web. We’ve moved from a world of web browsing to one of web editing, and our tools for manipulating this environment will reflect this shift.

I can say that I’m pretty helpless without a spell checker, and I am usually too lazy to use online tools like, so this will generally raise the bar of my online participation. Oh, and I won’t look like an idiot. As much.