Why Should Humans Index Books?

Language is very complex, so indexes prepared by computer or text searches are seriously lacking when compared to those written by a professional human indexer. The rest of this article points out some of the differences you’ll see between automatic indexes or searches and human-prepared ones.

Computers are so much faster than people at processing information. They can list instances of terms that appear in a book in a flash, and have the capability to perform full-text searches on electronic documents. So why on earth would anyone pay a human to index a book?

Automatic indexes can’t distinguish between homographs (words that are spelled the same way but have different meanings). An example given by the Society of Indexers is searching on the Internet for the pop stars Madonna and Prince. You’d find millions of unwanted references to religious art and royalty.

Also, text searches will not handle synonyms (words that have the same meaning) properly. For instance, a recent index we worked on used the words “bidding” and “pricing” interchangeably. An automatic search would have listings for each with only the pages where that specific word was used. We humans were able to see that these words were used in discussions about determining pricing for clients, so we listed them all under “pricing” but also made an entry for “bidding” with a “See pricing” reference so that someone looking up “bidding” could find all of the relevant information.

Computers also, unlike humans, can’t pick up concepts contained in the writing where your specific search term isn’t used. So you might look up “dog grooming” but miss a discussion called “Clipping Your Pet’s Nails.” They aren’t able to read the content of graphics, either, so you’d miss pictures that demonstrate brushing a dog’s hair but don’t have relevant captions.

Finally, the main problem with a search box or computer-generated index: they can’t tell whether a hit for a certain term gives you relevant information or just a passing mention. So they really give you concordances, lists of pages where a word appears in the text. There’s a big difference between a concordance and an index. Most of the terms we search for are not rare; they’re used very frequently. So they’d appear lots and lots of times in a concordance. To illustrate this, you might be interested in learning more about using Adobe Photoshop to edit images. So let’s say you look up “Photoshop” in a book on photography. You might find 100 places where that word was used, but many would lead you to sentences where the author says something like, “I like using Adobe Photoshop.” That’s all well and good, but is it really useful? Another example is in this article – in the third paragraph, I mention everyone’s favorite 80’s pop star, Madonna. But that paragraph isn’t really relevant to someone who wants to know more information about her, say, her first Top 40 single or her favorite brand of corset.

The point of an index is to help readers find the word they’re looking for and be taken to a useful discussion of it. So while a computer or search box can find that specific word really well, a human indexer can think from the reader’s point of view – what concept will they be searching for and what words would they use to find it? Writers put so much thought into carefully wording their books because they want to communicate the knowledge and experience they’ve worked so hard to obtain. The indexes for those books should be just as thoughtfully prepared so readers can get to that important information.