Seth Maislin's Indexing Blog

It should come as no surprise that information can be organized in many, many ways. According to Rosenfeld & Morville, there are two major types sorting schemes: exact (objective) and ambiguous (subjective). Personally, I like to imagine a third category, custom, that overlaps both and therefore deserves special treatment.

Exact sorting schemes are things like alphabetically ordered, numerically ordered, chronologically order, and spatially ordered. These schemes require that you follow an accepted and hopefully well-known sequence, such as from A to Z, from 1 to 9, or from top to bottom. Exact schemes do allow you to reverse order -- my blog, for example, sorts each entry in reverse chronological order, with the newest entries at the top -- but they don't allow you to start mixing things up. In an alphabetically ordered list of words, words starting with C will always appear between the B-words and the D-words.

There are three major problems with exact schemes:

• They assume that your audience knows the scheme. In most situations this isn't hard, but it's a big assumption. There are many native English speakers who still have to sing "The Alphabet Song" when trying to remember whether J comes before K. For spatially ordered data, the audience must know the associated spatial map; in the United States, there aren't many people who can tell you exactly where each state is. (People in New England, where I am, tend to have problems with the block-shaped states in the middle of the country; people outside of New England can't remember which tiny state is New Hampshire, and which tiny state is Vermont.)
  
• Your scheme is limited to its own items. Alphabetical order doesn't govern where numbers go. Some people sort numbers as if they were spelled out, putting "16 Candles" under S for sixteen. Other people will put all the numbers before the A-words, or after the Z-words. Punctuation also doesn't sort easily; which comes first, it's or its? And then there's the question of where spaces go (look up word-by-word sorting and letter-by-letter sorting) or if capitalization makes a difference (windows vs. Windows). I've given you all alphabetical examples, but the same is true in all other exact schemes. On a timeline, for example, how do handle repeating items? On a calendar of days, how do you record something that lasts two weeks, or breaks for lunch hour? Do you record time ranges (like hour-long appointments) as different from single moments (like 5:35pm)? In spatial ordering, how do you identify things that constantly move, or places that can be identified in multiple ways?
  
• Exact schemes have no meaning. It's true that A-words appear before B-words in the alphabet, but is that because B isn't a lesser letter? In a week that runs from Sunday to Saturday, why must an important Thursday event be buried in the middle? Do the units that make something sort a certain way -- the letters in a word's spelling -- have any meaning whatsoever? No, they don't. In fact, if you're going to sort something exactly, you have to completely ignore what it means and chop it into little meaningless or random components. If you have a friend whose name starts with Z, your friend knows what it's like to be treated as inferior for no valuable reason whatsoever.

Of course, these three reasons aren't enough to toss exact schemes into the rubbish bin completely. Exact schemes are easy. You can get a computer to sort things almost instantly, and most audiences have no trouble using them despite their shortcomings. However, my last point -- that they're meaningless -- is why there are so many better options.

I'll talk about ambiguous and custom schemes in my next posting.