API Concepts - Revision history

Scott at 19:39, 3 January 2014

2014-01-03T19:39:00Z

Scott at 19:38, 3 January 2014

2014-01-03T19:38:23Z

Scott at 05:31, 26 October 2009

2009-10-26T05:31:54Z

Scott: /* Unique Identifiers */

2009-06-15T23:51:21Z

‎Unique Identifiers

Scott: /* Tags */

2009-05-22T20:56:18Z

‎Tags

Scott: clarify

2009-05-20T05:07:19Z

clarify

Scott: add see also

2009-05-20T04:34:54Z

add see also

Scott: /* Links: Putting the pieces together */

2009-05-20T04:26:34Z

‎Links: Putting the pieces together

Scott: add examples of links

2009-05-20T04:08:34Z

add examples of links

Scott: /* Links: Putting the pieces together */

2009-05-20T02:37:46Z

‎Links: Putting the pieces together

@@ Line 76: / Line 76: @@
 : ''The relationship between this customer and this product is '''purchase'''.''
-Link types can be mixed and matched at query time.  So if you're asking for ''related products'' you can ask for a mix of recommendations based 80% on purchases and 20% on common tags by saying that you'd like 0.8 of the ''purchase'' link type and 0.2 of the ''tag'' link type.
+'''Link types can be mixed and matched at query time.'''  So if you're asking for ''related products'' you can ask for a mix of recommendations based 80% on purchases and 20% on common tags by saying that you'd like 0.8 of the ''purchase'' link type and 0.2 of the ''tag'' link type.
 You can create whatever link types seem appropriate for your site's data.

← Older revision		Revision as of 19:38, 3 January 2014
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	The only typical use case where this matters in using the API is that if you have friends in a social network, and the friendships are reciprocal (like Facebook) rather than possibly uni-directional (like Twitter), you have to put ''two'' links in there to convey the friendship.		The only typical use case where this matters in using the API is that if you have friends in a social network, and the friendships are reciprocal (like Facebook) rather than possibly uni-directional (like Twitter), you have to put ''two'' links in there to convey the friendship.
		+
		+	=== Link types ===
		+
		+	We've also introduced the notion of ''typed links''. '''Typed links''' specify something like:
		+
		+	: ''The relationship between this customer and this product is '''purchase'''.''
		+
		+	Link types can be mixed and matched at query time. So if you're asking for ''related products'' you can ask for a mix of recommendations based 80% on purchases and 20% on common tags by saying that you'd like 0.8 of the ''purchase'' link type and 0.2 of the ''tag'' link type.
		+
		+	You can create whatever link types seem appropriate for your site's data.

	== See Also ==		== See Also ==

@@ Line 62: / Line 62: @@
 === Directed edges ===
-You notice up there that those arrows aren't bi-directional?  They don't have a pointy thing on both sides?  Well, guess where the name of our company comes from:  those are ''directed edges''.  In graphs theory you can can undirected edges and directed edges.  All that ''directed'' means here is that they have a direction.  A connection from ''A'' to ''B'' is not the same as a connection from ''B'' to ''A''.  One says, ''Bob is a friend of Sarah'' and another implies ''Sarah is a friend of Bob''.
+You notice up there that those arrows aren't bi-directional?  They don't have a pointy thing on both sides?  Well, guess where the name of our company comes from:  those are ''directed edges''.  In graph theory you can have undirected edges and directed edges.  All that ''directed'' means here is that they have a direction.  A connection from ''A'' to ''B'' is not the same as a connection from ''B'' to ''A''.  One says, ''Bob is a friend of Sarah'' and another implies ''Sarah is a friend of Bob''.
 Web page ''A'' can link to web page ''B'' without implying that web page ''B'' also links back to web page ''A''.  That link is a ''directed edge''.

@@ Line 11: / Line 11: @@
 === Unique Identifiers ===
-Items have an identifier (''user_1'' and ''product_1'' in the example above).  That can't be changed once it's imported to the database.  It'd the handle that we use to grab a hold of things later on.  These ''must'' be unique.  Otherwise the database doesn't know how to tell two items apart.  You can use any scheme that you like to encode these.  Most people just use something like the type of the object (product, for example) and then the numeric ID that's stored in their SQL database, but you could also use the URL to a page here or anything else that makes sense for your data.
+Items have an identifier (''user_1'' and ''product_1'' in the example above).  That can't be changed once it's imported to the database.  It's the handle that we use to grab a hold of things later on.  These ''must'' be unique.  Otherwise the database doesn't know how to tell two items apart.  You can use any scheme that you like to encode these.  Most people just use something like the type of the object (product, for example) and then the numeric ID that's stored in their SQL database, but you could also use the URL to a page here or anything else that makes sense for your data.
 === Tags ===

← Older revision		Revision as of 20:56, 22 May 2009
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	Items can also have a collection of text tags. These are useful in filtering results later on. If you, for instance, wanted to find all of the books that are recommended for a certain user, it'd be useful to have some items tagged as ''book''. You can also give an item as many tags as you want, so it's no problem to have ''product'', ''book'' and ''sci-fi'' all associated with the same item.		Items can also have a collection of text tags. These are useful in filtering results later on. If you, for instance, wanted to find all of the books that are recommended for a certain user, it'd be useful to have some items tagged as ''book''. You can also give an item as many tags as you want, so it's no problem to have ''product'', ''book'' and ''sci-fi'' all associated with the same item.
		+
		+	Note however, that tags are just ways that we can label items; they're not actively used in finding similar items.

	=== Properties ===		=== Properties ===

@@ Line 43: / Line 43: @@
 [[Image:user-product-link.png]]
-So, now we're ready to present the second major building block of the Directed Edge engine &mdash; links.
+'''An ''edge'' is just the math term for what we call a ''link''.  They're the connections.'''
-On the one hand every ''object'' in the Directed Edge database is an ''item''.  But relationships are encoded as ''links''.
+Every ''object'' in the Directed Edge database is an ''item''; the relationships between them are ''links''.
 === Examples of links ===

← Older revision		Revision as of 04:34, 20 May 2009
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	The only typical use case where this matters in using the API is that if you have friends in a social network, and the friendships are reciprocal (like Facebook) rather than possibly uni-directional (like Twitter), you have to put ''two'' links in there to convey the friendship.		The only typical use case where this matters in using the API is that if you have friends in a social network, and the friendships are reciprocal (like Facebook) rather than possibly uni-directional (like Twitter), you have to put ''two'' links in there to convey the friendship.
		+
		+	== See Also ==
		+
		+	* [[Introduction to Recommendations]] for the basics on how recommendations work.
		+	* [[XML Format]] for information on how to represent these lovely concepts in simple XML.
		+	* [[REST API]] for documentation on communicating with our webservices.

@@ Line 29: / Line 29: @@
 At the moment properties aren't used at all by the recommendations algorithms, but we may add support for doing that later.  For now they're just a convenient way of keeping tabs on the information that is being recommended.
-== Links:  Putting the pieces together ==
+== Links, or ''the way you connect stuff'' ==
 So, we're huge [[Wikipedia:Graph theory|graph theory]] wonks.  No, no, not like Excel.  Like webs of information.
@@ Line 47: / Line 47: @@
 On the one hand every ''object'' in the Directed Edge database is an ''item''.  But relationships are encoded as ''links''.
-A few examples of links include:
+=== Examples of links ===
 * A '''user (item) purchases a product (item)''', so we make a link from the user to the product.
@@ Line 55: / Line 55: @@
 * A '''user (item) is a fan of a band (item)''', so we make a link from the user to the band.
 * A '''web page (item) is connected to another web page (item)''', so we make a link from the first page to the second page (just mimicking the HTML link structure).

← Older revision		Revision as of 04:08, 20 May 2009
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	So, now we're ready to present the second major building block of the Directed Edge engine — links.		So, now we're ready to present the second major building block of the Directed Edge engine — links.
		+
		+	On the one hand every ''object'' in the Directed Edge database is an ''item''. But relationships are encoded as ''links''.
		+
		+	A few examples of links include:
		+
		+	* A '''user (item) purchases a product (item)''', so we make a link from the user to the product.
		+	* A '''user (item) gives a rating of 5 to a product (item)''', so we create a link between the user and the product with a ''weight'' of 5.
		+	* A '''user (item) clicks on a product category (item)''', so we make a link from the user to the category page.
		+	* A '''user (item) is friends with another user (item)''', so we make a link from the user to the other user.
		+	* A '''user (item) is a fan of a band (item)''', so we make a link from the user to the band.
		+	* A '''web page (item) is connected to another web page (item)''', so we make a link from the first page to the second page (just mimicking the HTML link structure).

← Older revision		Revision as of 02:37, 20 May 2009
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	In computer science lingo, a graph is just a sets of connections between items. Those connections are called ''edges'' and the items are called ''nodes''. All sorts of things can be modeled in graphs, like the way that web pages are connected to each other (there the links between pages are ''edges''), or as above, a set of friends in a social network.		In computer science lingo, a graph is just a sets of connections between items. Those connections are called ''edges'' and the items are called ''nodes''. All sorts of things can be modeled in graphs, like the way that web pages are connected to each other (there the links between pages are ''edges''), or as above, a set of friends in a social network.
		+
		+	'''Let's make this really easy just to be clear: ''a graph is just a collection of connected stuff.'' '''

	Here's an example of the two ''items'' from above connected via an ''edge''. This would indicate, for instance, that the user had bought that product.		Here's an example of the two ''items'' from above connected via an ''edge''. This would indicate, for instance, that the user had bought that product.