It’s a long-standing complaint of mine with Google. You can do a search, then repeat the same search and “subtract” a word from your original set, and Google will return more matches — not less. It shouldn’t happen. But does, and here’s why. Subtracting Gives You More? Consider a search for cars, which reports that there are 546,000,000 pages that match that word: Now consider a search for cars -used, which should find all the pages that are relevant to the word cars (a set of 546 million) and then subtract any pages that have the word “used” on them. The figure should be less than 546 million. But it’s not. Instead, the set increases by 115 million matches, to 661,000,000 in total: It makes no sense. It’s irked me for years. It was the top item on my “25 Things I Hate About Google” story that I wrote in 2006: 1) Web search counts that make no sense. “Why do search engines lie?” has Robert Scoble … [Read more...] about Why Google Can’t Count Results Properly