The problem with AND as a default is that 'normal' people (i.e. people who have no idea what boolean means) operate search engines something like this: 1. type some words in, and get no or incorrect results; 2. add some extra words, and repeat the search, with the idea they are making the search more specific; 3. be confused as to why they still don't get the results they want. a default of OR, on the other hand, means adding search terms ends up being useful...

As someone old enough to have used search engines extensively myself and watching over others using it during the AV - Google transition, I can definitely say that defaulting to AND was one of the most important reasons Google appeared to give better results than AV for both advanced and basic folk.

Defaulting to AND means that you aren't just searching for the most common term in your query that drowns out the rest. Also, adding terms narrows the query down rather than making it more general. This behavior strikes me as far more natural for "normal" people.

sure, i agree, except that they also apply this 'narrowing down' logic when insufficient or no results are returned, thinking the query needs to be more specific in order to work. i have observed the following sort of behaviour:

    1. entering 'invisible marmalade teapot' and getting no results
    2. changing to 'invisible marmalade teapot with tartan cosy', again nothing
    3. so 'invisible marmalade teapot with tartan cosy in outer space', ditto

you get the idea...? it's just like in the real world, when you might go to a bookshop and say

    You: do you have that new crime novel in stock?
    Bookseller: er, i don't know which one you mean?
    Y: the new crime novel by john grisham, pelican something or other?
    B: oh, right, yes, here it is!

and everyone is happy.

default OR in a search engine would mean my first example eventually starting to return results about transparent space coffee pots with tartan cosies, ignoring the first few terms but the rest match, which is often helpful, particularly if you're doing an exploratory search for something where you aren't sure of the exact details.

`eventually starting to return results about transparent space coffee pots with tartan cosies ... which is often helpful`

I don't find your examples compelling.

If you want to do an additional search that does not depend on your first terms, you simply bring up a new search window.

In your 'real world' example, the equivalent search queries would go something like

search: new crime novel

result: way way too much stuff

search: new crime novel john grisham pelican

result: exactly the right book because every one of those terms applies

Hm. I think perhaps a better way of putting it is that the hard AND issue is when people search using a natural language type query (I know about stop words, assume these are always filtered out) and include some extraneous term, so 'What is that new crime novel by John Grisham about a Penguin I think?' will return nothing, and no amount of extra terms added at the end will help, until you delete 'Penguin'... Of course it's anecdotal, but I still suspect it's one of the reasons for the hard AND to OR switch...

Amazon's search seems to be OR. It isn't very good.

As of the past 2 weeks Amazon's search feels like "we're not even going to try to get close anymore and aren't even going to show you matches that contain the words you're looking for, here are some random stuff plus some things you looked at recently".

Apple’s App Store search and Microsoft’s Store’s search seems to be * no matter what you type in.

Back then there was also a distict possibility that there was indeed not a single web page written about a given topic.

Reminds me of a Google Whack: a two word query that returned exactly one result. Mine was zoomorphic kazoos. Those days are gone.

> Those days are gone.

9130 webpages agree with you.

There is a verbatim mode?

Yes, easily discoverable from the links under the search box as Tools -> All Results -> Verbatim. Ignore the sign about the leopard, I think that's just left over from some other project.

I assume this refers to encapsulating the entire search text in quotes.

No, it refers to verbatim mode, which ensures every word in the search is on (almost) every page found. (You would think google works like this by default, but in practise, very far from it) Using quotes around the search terms ensure they appear in the quoted order.

To switch on Verbatim, I click "Verbatim" on the left side of the google page, it appears just under the alternative, "All results". I think for other systems it can be well hidden in menus. I use it almost every time I google anything. Otherwise you get a load of irrelevant crap.