The Magical Number 7+-2

July 25, 2007

From time to time I witness the wide gap between theory and practice in the field of interaction design and information architecture. I often witness this when simpletons (those who take a non-theoretical and non-scholarly approach to everything in life because they always think everything is black and white) attempt to practice what should be left to those who are better educated. This often comes in the form of misapplying good research findings to areas of practice for which it was never intended.

Ask any information architect or interaction designer and they will undoubtedly tell you that they have heard of “the magical number 7 +-2” principle. However, despite its wide use and popularity, I’ll bet that few would be able to tell you the origins of it. The idea comes directly from a 1956 research study by the cognitive scientist George Miller. In his study, he suggests that the capacity of short-term memory is within the range of 5-8 items. Miller was primarily writing about short-term memory span for digits, but an item could include something more complex such as a long word. He also introduced the idea of “chunking” which means we are able to group similar items together to form one item (such as a string of letters to form one word).

Other studies have been conducted since then that suggest that the capacity for short-term memory is much less. Also other studies suggest that the capacity may vary depending on the type of information (visual, spatial, phonological). What also complicates matters are issues of interference and attention.

The reason why applying such research to the practice of design and information architecture could be dangerous is because there are so many confounding variables in a real-world environment. This is, of course, assuming that the principles were applied correctly. However, the findings of Miller’s research study is often misapplied, as is apparent when some designers and information architects say things like . . . “because people can only hold 5-9 items in short-term memory, I decided that there should only be 7 menu items on this website, or 7 icons, or 7 bulleted items in a category, or 7 subdivisions on the homepage . . . ” and on and on and on. What does Miller’s study have to do with the number of tabs on the top of a web page? Such practices are not the implications of his study! Please spread the word.

Source:  Yvonne Rogers, “New theoretical approaches for human-computer interaction.”
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Menus in Minutes: A recipe info. system for home cook enthusiasts

May 30, 2007

“Menus in Minutes” was the name of my group’s final project in “Systems Analysis and Design” in Winter 2007. Tonight I had intended to write a postscript that includes my personal reflections, comments received, and new insights I have gained as to how our project could be improved if we had another 10 weeks to work on it.

However, I realized that I never posted a single blog entry, so in order to correct this, I will post a few entries that will cover the following topics:

  • What the project was and how it all came together into the form you can see (you can download the written report).
  • Comments we received from Professors Agre and Borgman, as well as comments received when interviewing for internships in April.
  • New insights I have gained from new classes and a considerable amount of reflection.

All of this is in retrospect of course, so my new found 20/20 vision will be mixed in with my group’s thinking at the time.

Let me know what you think!


“When is the pen mightier than the keyboard?”

April 4, 2007

I attended a lecture recently with this title given by Andreis Van Dam from Brown University. It was a demonstration lecture on computer software applications his research team is developing which uses a pen rather than a mouse or a keyboard to interact with the software. The demonstrations were amazing to say the least and I was awed and inspired by what I saw.

Dr. Van Dam said that pen-centric computing takes advantage of the pen which is more than a high resolution mouse. The pen interprets “digital ink” in an appropriate context for characters, symbols, gestures, etc. He said that the best example of this so far is how the Palm Pilot feature called “graffiti” that interprets users’ gestures for alphanumeric characters. He also said that pen-centric computing is best if it is used with speech and other modes.

One application he showed us was one in which you can write music. You use a pen on something like a tablet PC and you make simple gestures to indicate the notes you want. So how do users know which gestures to make? Well, the software is designed so that the gestures correspond to what they are already familiar with in that given context. One thing that was suprising was that users are only willing to learn 12 new gestures: they are not willing to spend alot of time learning all the gestures, especially if the gestures are unintuitive.

I will write more entries on this lecture at a later time.


Information and Documentation: A look at restaurant menus

April 2, 2007

What is information and what is documentation? I started thinking about this last week when I was dining at California Pizza Kitchen with a friend. I lost about 30 lbs. during the summer, and I try my best to lose even more by eating healthy. You know how some restaurants have symbols denoting certain health information about their menu items. Some places place a chili by an item description, signifying that it is spicy; sometimes they place a heart by a dish that is supposedly low cholesterol/low saturated fat.

Obviously, each menu item has a plethora of nutrition information. Information exists everywhere, whether we are aware of it or not, but it is documentation that allows us to know what that information is and make meaning from it. I like Suzanne Briet’s idea that a document is information from the natural world that has been captured and made an object of study. Some restaraunts choose to capture some of the nutrition information and document it using symbols like a heart or chili. But why don’t restaurants document all of the nutrition information including calories, fat content, and cholesterol? Does the absence of a heart next to a menu item mean that it is a “heart attack on a plate?” Why does a heart signify heart-healthy? Why can’t a heart next to a menu description mean that it is a heart-attack on a plate? I bet we can find many menu items at restaurants that are unhealthy. A fellow colleague from the department told me that she doesn’t mind advertisements because they are merely free information. True, but not all of the information is documented. Only the information favorable to them is documented. It’s always important to remember who is doing the documenting. I doubt that a restaurant like Chilis or CPK would ever want to document all the nutrition information on each menu item (probably because most of it is unhealthy and nobody would eat there if they knew that what they just ordered has the calories equivalent to three days of eating).


Plagiarism in Blogs

February 24, 2007

I’ve been thinking alot about plagiarism on the Internet. I have always thought of plagiarism in the specific context of people taking information off the Internet and replicating it into the paper they turn in for class w/o crediting the source.

Recently, though, I have been thinking of plagiarism that takes place when a blogger takes the content of someone else’s blog and posts it into their own blog without crediting the source. How could plagiarism even be verified in this case? Who is to say that the plagiariser didn’t come up with the content first, and the other person copied it? Who is the original creator? Who owes what to whom?


Searching iTunes

February 24, 2007

I have had iTunes for more than a year, and it is the main software I use to buy and organize my music.  My information science courses have begun to make me think about how “information packages” are indexed.  In other words, what parts make up the information package, what are those parts named, and what level of granularity?

From the interface, I can ascertain that the songs are indexed by name, time, artist, album, price, popularity, and genre.  These elements/fields and the content in them can be though of as metadata, and together, these parts desribe the entire song.  However, users are not able to search all of these fields.  The search box does not allow users to limit their searches to song name, or album, or anything else.  Users are forced to type something into their search box, and whala, all of these things pop up.  The results you get could be because your search term is part of a song title, an album, or whatever.  Either way, it is all mixed up.  Try searching for “beetles” and you’ll see what I mean.

Besides allowing users to search the fields that iTunes already indexes, it should also index the lyrics of songs (just the keywords), so that users can search by lyrics.  How many times have you known the lyrics of the song you wanted, but couldn’t remember the title?  The access points to song records should not exclude keywords in the lyrics.


Our PCs a digital library? Is every PC owner a digital librarian?

February 16, 2007

For one of my classes, groups are suppose to build and manage a digital collection of “information packages” using Contentdm. It’s almost like a miniature digital library. It got me thinking about how much digital content we all have on our computers and how, in a way, we each have created our own digital library, thus becoming digital librarians. We all probably have the following on our computers: Word documents, PDF docs, HTML files, graphics, photos, music collections, audiofiles, video, bookmarked web sites, cookies, viruses(?), personal data, browsing history, format/display settings, clipboard items, etc. It’s also interesting how we all try to organize and manage all of this information using folders, creating hierarchies of folders, specifying locations (desktop, folder, recycling bin, etc.). We create metadata by naming these files and folders that we create. We also control that information because we, ourselves, make the decisions on what is collected (i.e. saved), what it is named, where it is stored, when it gets deleted, who has access to it (user names and passwords–admin. rights).

So are our computers a digital library? Are we digital librarians? Well, let’s take a look at the definition of a digital library. Arlene Taylor in her book The Organization of Information defines digital libraries as “a collection of information packages in digital form that are selected, brought together, organized, preserved, and to which access is provided over digital networks for a particular community of users.”

I would say that we each fit that definition pretty well. Congratulations.