Ask HN: Why do search engines ignore the exclusion operator now “-”?

20 ポイント投稿者 kristopolous5 年前14 コメント

Google, Bing, Duckduckgo, Yahoo, it seems like all of them have decided to stop honoring the "-". Surround things by quotes, add them multiple times, it doesn't seem to matter.

Are there any decent search engines that do what you actually say left instead of extremely poorly trying to guess what you mean?

14 コメント

bjourne5 年前

Because negation is incredibly expensive in any information retrieval system. You want all recipes with blue cheese in them? That's easy. You want all recipes with no blue cheese in them? That's a massive number of recipes.

jobigoud5 年前

Still less than all the recipes, which would also be a valid search so I don't think this point stands.

bjourne5 年前

What query do you use to get Google to list all documents in its index?

solus_factor5 年前

Quotes are also pretty much ignored now. I don't know why.

aww_dang5 年前

-"negative keyword"

appears to work for me

blackcats5 年前

Don’t know, some spam sites show up in my google search like codegrepper. Sticking with queckqueckgo i guess

decasteve5 年前

The cynical take:

They'll do what's profitable over what's accurate.

mxmilkb5 年前

I noticed it's like this on Amazon the other day. It meant I couldn't narrow down results to find what I wanted so I could give Amazon money

scrollaway5 年前

This isn't a cynical comment, it's just nonsensical in this context.

It's like replying "it's more profitable this way" to "why are chopsticks popular in asian culture".

Ulus5 年前

I just did a google search for “league of -legends” (sans quotes) and it didn’t return links to the game.

kristopolous5 年前

This is absolutely true. I wonder why I always hit the edge cases.

rozab5 年前

I use this feature all the time. Maybe you're getting A/B tested?

kristopolous5 年前

I try to use it all the time. I've done crude things like written browser plugins to sift through results and remove things because the search engines just ignore it.

The worst thing is when I'm trying to remove garbage results so things like "free account" or "need to signup" for a bunch of spam sites. Those things are always ignored.

It's stupid that I need to essentially groom my results with my own code.

matt_heimer5 年前

Google still has it documented on https://support.google.com/websearch/answer/2466433 and there is a none of these words option on https://www.google.com/advanced_search

Make sure you aren't putting the minus symbol in quotes. The quotes are what I see people get wrong. Many people still try to use the + symbol to indicate required but Google disabled that when working on Google+ and switched to quotes to indicate required words or phrases.