We’ve been talking quite a bit about bad indexes, without being clear about what we mean. So let’s fix that briefly. Here’s a semi-comprehensive list of ways that an index can go wrong.

Let’s call them The Seven Deadly Sins of Book Indexing 

(1) Over-indexing and under-indexing are what it sounds like — either focusing too closely on minutiae or missing important topics. Certainly this is a pernicious problem for a number of books (and even professional indexers). Remember the quote above about a skimpy index.

(2) Poor style & formatting refers to any ways that an index fails to follow established style guidelines (about things like indentations, alphabetization, capitalization, spacing, etc.) or is inconsistent. Above all this is a much bigger problem for amateur indexers, especially authors who index their own books.

(3) Undifferentiated entries. A good rule of thumb for indexers is to have a maximum of 7-8 entries for a topic.

Elm Trees, 6, 18, 34, 107, 232-4, 267, 301, 321-3, 345

Longer than that, and the indexer should use sub-headings.

Elm Trees, 6, 18, 34
life cycle, 321-3, 345
maintenance of, 232-4, 267
planting of, 107

The best indexers try to keep the number of undifferentiated entries somewhere around 5. In the article mentioned before, Sam Leith comments that,

“One of my correspondents recently bewailed the index of a major and bestselling recent book.
‘Entry for France – around 40 undifferentiated locators,’ she complained. ‘Entry for Europe, over 90 page refs.’
She concluded: ‘Looks like a concordance created by searching the PDF files.’”

 (4) Circular Cross References. This is when an index sends readers around the index in a circle,

subway 68, 74, 81; see also metro
metro 68, 74, 81; see also subway

(5) Indexing the Metatopic. If the book is about Andrew Jackson, for instance. It probably doesn’t make sense to have 1453 entries for Andrew Jackson since, probably, every part of the book should be about him.

(6) Same Word Variations.

This is probably more of an amateur’s mistake when doing book indexing. But it’s when an index has entries for variations of the same word or concept.

disgust, 16, 84, 96,
disgusting, 21, 34, 89, 116

Where everything should just be combined under “disgust.”

disgust, 16, 21, 34, 84, 89, 96, 116

(7) Adjectives & Verbs Indexing. Finally, a good index should contain only nouns. Above all it doesn’t make sense to have entries like these,

greatest athlete
incredible view
short men

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