Amazon Product Advertising API Developer's Manual page 328

Product Advertising API Developer Guide
Value
reviewrank
SearchIndex: Books
Value
salesrank
pricerank
-pricerank
daterank
titlerank
-titlerank
reviewrank
SearchIndex: Electronics
Value
salesrank
price
-price
titlerank
-titlerank
release-date
-release-date
SearchIndex: Grocery
Value
relevancerank
salesrank
price
-price
Sort Values for CN
Description
Average customer review: High to low
Description
Best to worse selling
Price: Low to high
Price: High to low
Publish date: New to old
Alphabetical: A to Z
Alphabetical: Z to A
Average customer review: High to low
Description
Best to worse selling
Price: Low to high
Price: High to low
Alphabetical: A to Z
Alphabetical: Z to A
Release date: Older to newer
Release date: Newer to older
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), how closely
they occur in descriptions (if there are multiple keywords), and how
often customers purchased the products they found using the
keyword.
Best to worse selling
Price: Low to high
Price: High to low
API Version 2011-08-01
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