All Blogs

A Heuristic evaluation is a process where someone trained in usability principles reviews an application (a website or software). She compares the website against a set of guidelines or principles ("Heuristics") that tend to make for more usable applications. For example, if while completing a task a user gets a message that says "Error 1000xz Contact System Administrator" this would violate a Heuristic: "Error messages

Read More

If you've ever designed a survey or questionnaire you've probably wondered how many points the response options should have. Most questionnaires I've examined either use five point scales or seven-point scales.  Is one better? 7-point scales are slightly better The short answer is that 7-point scales are a little better than 5-points—but not by much. The psychometric literature suggests that having more scale points is

Read More

      Does this man need back surgery? Does this woman have breast cancer? Does this website have usability problems? Chances are you're not qualified to answer the first two questions but probably able to provide some answers about the third.  This image comes from the Hotel Pennsylvania website. It was the subject of the Comparative Usability Evaluation (CUE-4). Seventeen usability teams independently evaluated

Read More

Love them, hate them, admire them or ignore them. These seven living legends aren't one-hit wonders. Their work has had and will continue to have a large impact on the field of usability for some time. Here they are in alphabetical order:   1. Joe Dumas "Dr Usability" is author of dozens of articles on usability. His twenty-year old book "A Practical Guide to Usability

Read More

I write a lot about the importance of confidence intervals and making the most of small sample sizes. Recently, Dean Barker, director of UX at Sage CRM read one of the articles on margins of error and sample sizes and said: "I understand there is variability with small samples but I'm having a hard time reconciling the numbers with my experience."   Math Dean was

Read More

Recently Nielsen conducted a study on the reading speeds between the printed book, Kindle and iPad. From 24 users the study concluded that the iPad took about 6.2% longer (p =.06) and Kindle about 10% longer (p <.01) to read than the same story on a printed book. From this data Nielsen concluded "Books Faster than Tablets" and while tablets have improved dramatically over the

Read More

Wondering about the origins of the sample size controversy in the usability profession?  Here is an annotated timeline of the major events and papers which continue to shape this topic. The Pre-Cambrian Era (Up to 1982) It's the dawn of Usability Evaluation and the first indications of diminishing returns in problem discovery are emerging. 1981: Alphonse Chapanis and colleagues suggest that observing about five to

Read More

Will users purchase an upgrade? What features are most desired?  Will they recommend the product to a friend? Part of measuring the user experience involves directly asking users what they think via surveys. The Web has made surveys easy to administer and deliver. It hasn't made the question of how many people you need to survey any easier though. One common question is "How many

Read More

I compiled a list of papers that have had a large and lasting influence on the field of Usability and User Experience. I then asked Jim Lewis and Joe Dumas, two pioneers in this field for their top five.  There was considerable overlap in both the papers and topics suggesting that while there may be some disagreement with the conclusions of the papers there is

Read More

When babies are born in the hospital nurses measure every feeding and diaper change. When you want to lose weight with Weight Watchers you log everything you eat using a point system. When you want to improve usability beyond obvious problems you need to record: symptoms:  lower completion rates, lower satisfaction ratings, longer task times or more errors. causes:  what design elements are leading to

Read More