k',
'price' => 'price',
'-price' => '-price',
'most-recent' => 'daterank',
'title' => 'titlerank',
'-title' => '-titlerank'),
'Merchants' => array(
'relevance' => 'relevancerank',
'salesrank' => 'salesrank',
'price' => 'pricerank',
'-price' => 'inverseprice',
'most-recent' => '-launch-date',
'sale-flag' => 'sale-flag'),
'Miscellaneous' => array(
'featured' => 'pmrank',
'salesrank' => 'salesrank',
'price' => 'price',
'-price' => '-price',
'title' => 'titlerank',
'-title' => '-titlerank'),
'Music' => array(
'featured' => 'psrank',
'salesrank' => 'salesrank',
'price' => 'price',
'-price' => '-price',
'title' => 'titlerank',
'-title' => '-titlerank',
'artist' => 'artistrank',
'most-recent' => 'orig-rel-date'),
'MusicalInstruments' => array(
'featured' => 'pmrank',
'salesrank' => 'salesrank',
'price' => 'price',
'-price' => '-price',
'most-recent' => '-launch-date',
'sale-flag' => 'sale-flag'),
'MusicTracks' => array(
'title' => 'titlerank',
'-title' => '-titlerank'),
'OfficeProducts' => array(
'featured' => 'pmrank',
'salesrank' => 'salesrank',
'review' => 'reviewrank',
'price' => 'price',
'-price' => '-price',
'title' => 'titlerank'),
'OutdoorLiving' => array(
'featured' => 'psrank',
'salesrank' => 'salesrank',
'price' => 'price',
'-price' => '-price',
'title' => 'titlerank',
'-title'