Assignment 3: Craigslist

Michael (menewman@)
Neil (neilc@)
Andrew (acallaha@)

Site being evaluated: Craigslist

i. Most severe problems, how they fit into Nielsen’s heuristic categories, suggestions to fix UI, and how suggestions are related to heuristic categories

Craigslist’s functionality is based on a user’s ability to search for old posts and create new posts. Unfortunately, for both searching and posting, there is a lot of noise (H8). Users might find it difficult to find what they want when sifting through verbose postings. There are hints on how to post, but one has to actively seek them out in the help section. Additionally, there aren’t really any suggestions on how to search. If your search gets 0 hits, there aren’t really any recommendations on how to improve or alter your search — it’s a very binary response, matches or no matches. Between inefficient searching and confusing posting, the site can be difficult for a user to navigate.

Most of the searching problems fall under H7 and H8, with users frequently unable to filter out postings that are useless to them. For example, a user searching for an apartment cannot restrict basic categories, such as specific neighborhood, size, number of bedrooms/bathrooms, and lease terms/duration. A user searching for a job likewise cannot filter for even basic categories like expected salary. Craigslist could greatly accelerate the process of finding what you’re looking for by including feature lists specific to the category you’re browsing. This is something Amazon does very naturally:

In addition to the obvious aesthetic problems with the site, we took issue with the error messages received when trying to submit a post without certain required fields. There is apparently a minimum description length, but even after getting an error message the site didn’t specify how long the description needed to be for the post to get through. This violates not only Nielsen’s H9 (help users recognize, diagnose, and recover from errors), but also H5 (error prevention), since the site does not give prior warning that those fields are necessary to submit a post. A better way to handle this would be to explicitly spell out mandatory field requirements to users when they’re typing up their posts — and if a user does leave out a field or type an overly short post, Craigslist should be more specific about what needs to be corrected before the post can go through.

ii. Problems that were made easier to find/correct by list of Nielson’s heuristics

We believe that Nielson’s heuristics prepared us to find problems with aesthetics and error prevention/messages in particular. In general, the list of heuristics definitely allows a systematic approach to finding errors. H8, for example, provides insight into a fundamental usability concern of any system — reducing noise. The heuristics help you look for fundamental errors by creating broad and easily understandable categories for different types of problems.

iii. Usability problems not included under any of Nielsen’s heuristics, and proposed additional heuristics

Search functionality isn’t specifically included under any of the heuristics (more generally, the ability to find things on the site), although obviously the heuristics are broad enough to encompass the general idea. A new, more specific heuristic might be something like “ability to search intuitively and specifically for content.”

Also, the problem of terrible posts (expired, weird, incomprehensible) due to lack of oversight/moderation doesn’t fall neatly into a specific heuristic — perhaps there should be a heuristic for the curating of user-submitted content.

iv. Useful class discussion/final exam questions related to heuristic evaluation

Are some of the heuristics more intrinsically important than others? (On Craigslist, for example, it seems that aesthetics violations are by far the worst offenders, but does that mean that aesthetics are more important than, say, error prevention or similarity to the real world?)

Does the number of heuristics violated predict the usability (or lack thereof) of a site? (That is, if a site violates a bunch of different heuristics, but only slightly, is that better or worse than a different site that violates a single heuristic but violates it very badly?)

Links to individual heuristic assessments:



Click to access P3.pdf