Archive for April, 2009

News Summary

Monday, April 27th, 2009

I’m moving news items from my design home page to a new blog category called News (unimaginative, I know). Here is a summary of news for 2008/2009.

We presented three courses and a short paper at the CHI 2009 conference in Boston. This puts us on a par with Carnegie Mellon (who also had three courses but slightly more papers<g>):

  • Innovations in Card Sorting: A Hands-on Approach
  • Web Design for Usability
  • Ajax – Design and Usability

(These courses can also be run in-house. Details are available at

We’ve posted the slides and a recording from our half-our card sorting webinar, plus four videos showing how to prepare for and capture data from card sorting sessions.

The paper concerns a study we conducted using Simon Baron-Cohen’s empathising and systemising quotients. It provides a psychological explanation for the difficulties technologists have in seeing problems from a user’s perspective:

William Hudson was the invited keynote speaker for the CADUI 2008 conference in Albacete (near Madrid). He also presented a half-day tutorial on card sorting. An essay based on his keynote address is available here.

Do you like using or teaching Card, Moran and Newell’s Keystroke Level Model but hate the arithmetic? Treat yourself to our free KLM calculator!

Bandwagon Cues – To Jump or Not to Jump?

Friday, April 24th, 2009

Continuing on the theme of new research from the CHI 2009 conference, I came across another interesting poster – this time from Penn State University (S. Shyam Sundar, Qian Xu and Anne Oeldorf-Hirsch, “Authority vs. Peer: How Interface Cues Influence Users”). Here the researchers were considering the effect of an authoritative logo and customer comments on purchase intention, participants’ product attitudes and a raft of other factors they referred to as “bandwagon perceptions”.

For the studies they used a typical product page, as shown in Figure 1 (adapted from Amazon). The “authority” seal shown (above the camera) was either for a fictitious organisation (Zig! as displayed here) or for CNET, a well-known technology review site (or it was absent altogether). Both seals were fairly similar in appearance.

Typical product page showing Zip! authority seal 

Figure 1: Typical Product Page

The researchers also made use of “outlying reviews” – that is, one where the reviewer expressed dissatisfaction with a product, even though the average score among all reviewers was high. So, in summary, there were two main effects of interest: faux versus “real” authority logo and presence or absence of “outlying” (dissenting) review.

Some of the reported results are as might be expected, but there was one very interesting interaction between the authority seal and an outlying review:

  • When no authority seal was shown, the presence of an outlying review had no effect on purchase intention
  • When the CNET seal was shown, purchase intention was contingent on the absence of an outlying review (that is, an outlying review reduced the likelihood of purchase)
  • When the Zig! Seal was shown, the situation was reversed (that is, an outlying review increased the likelihood of purchase)

The relatioship between the seals and the presence of outliers is shown in Figure 2. Needless to say, this final point – that purchasing intention increase with an outlying review – is somewhat counter-intuitive. The researchers offer no explanation for it and I have none to offer. It would be interesting to know whether other studies show any similar effect. I’ll write more on this if something turns up!

Chart showing negative effect of outlying review with CNET seal and opposite for Zig! seal

Figure 2: Purchasing Intention by Seal Condition and Presence of Outlying Review 

Facial Avoidance in Page Design

Monday, April 20th, 2009

I am a great admirer of Tom Tullis’s work. He’s made important contributions to our understanding of screen design over the years (plus he is even older than me, which gives me great cause for hope!). In a recent poster at CHI 2009, in collaboration with Fidelity Investment colleagues Marisa Siegel and Emily Sun, Tom has done it again. He explained to me their important findings on the use of face images to attract attention on web or intranet pages. The results certainly run contrary to the perceived wisdom in this area (that humans are naturally attracted to facial images).

The Fidelity studies show that not only were users disinclined to look at facial images of the type shown in Figure 1, but that a significant number of users were unable to find the text immediately adjacent when given a task requiring that information.

Box containing facial image next to link text

Figure 1: Link panels with and without facial image (Study II)

In fact, overall performance was negatively affected by the presence of the face: accuracy dropped from 93% to 78%, mean time on task increased from 37 to 54 seconds and perceived task ease dropped from 4.2 to 3.4 (on a 5-point scale).

In a separate study, Tullis and colleagues not only found that facial images reduced performance; they also had the completely unexpected effect of reducing user confidence. Figure 2 shows the quite common approach that was tested (with and without the images). Again accuracy dropped, but this time by a smaller margin, from 94% to 87%. However, trust also dropped, from 6.3 to 6.0 on a 7-point scale. This result may seem small but there is only a 5% probability of it being due only to chance, which is taken by statisticians to mean that it was significant.

 Box show author images next to link text

Figure 2: Authors’ images reduced trust in content (Study III)

So, contrary to what I remember being told in design seminars years ago, and even contrary to advice that I would have given up until I saw these studies (typified by my article on using images as links – it looks like we need to be careful about how we use facial images in particular.

(You can see the full work-in-progress paper in the CHI 2009 proceedings, which will eventually be available from the ACM Digital Library –