Amazon Product Advertising API Developer's Manual page 358

Product Advertising API Developer Guide
Value
relevancerank
reviewrank
salesrank
SearchIndex: Outlet
You cannot use any sort parameters with the Outlet search index.
SearchIndex: Shoes
Value
price
-price
relevancerank
salesrank
reviewrank
SearchIndex: PCHardware
Value
psrank
salesrank
price
-price
titlerank
Sort Values for FR
Description
Items ranked according to the following criteria: how often the keyword
appears in the description, where the keyword appears, for example,
the ranking is higher when keywords are found in titles, and, if there
are multiple keywords, how closely they occur in descriptions, and,
finally, how often customers purchased the products they found using
the keyword.
Highest to lowest ratings in customer reviews.
Bestselling
Description
Price: low to high
Price: high to low
Items ranked according to the following criteria: how often the keyword
appears in the description, where the keyword appears, for example,
the ranking is higher when keywords are found in titles, and, if there
are multiple keywords, how closely they occur in descriptions, and,
finally, how often customers purchased the products they found using
the keyword.
Bestselling
Highest to lowest ratings in customer reviews.
Description
Bestselling
Price: low to high
Price: high to low
Alphabetical: A to Z
API Version 2011-08-01
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