The correlation between gpm and Win Rate is 0.68. The more gpm, the more Win Rate, and vice versa. But some values are higher than expected, some are lower. Efficiency is a difference between the value of Win Rate depending on gpm (blue dots) with respect to the expected value (red line).
Efficiency
Stormcrafter 0.0601
Telescope 0.0531
Book Of The Dead 0.0438
Ceremonial Robe 0.0395
Arcanist'S Armor 0.0359
Timeless Relic 0.0325
Spell Prism 0.0312
Quickening Charm 0.0237
Ascetic'S Cap 0.0230
Bullwhip 0.0211
Psychic Headband 0.0204
Dandelion Amulet 0.0204
Arcane Ring 0.0187
Seer Stone 0.0161
Martyr'S Plate 0.0109
Giant'S Ring 0.0098
Seeds Of Serenity 0.0093
Eye Of The Vizier 0.0091
Cloak Of Flames 0.0084
Defiant Shell 0.0079
Trusty Shovel 0.0078
Ring Of Aquila 0.0056
Havoc Hammer 0.0047
Force Boots 0.0045
Mirror Shield 0.0028
Gossamer Cape 0.0021
Mind Breaker -0.0006
Penta-Edged Sword -0.0030
Fallen Sky -0.0040
Book Of Shadows -0.0067
Fairy'S Trinket -0.0074
Ninja Gear -0.0077
Enchanted Quiver -0.0086
Trickster Cloak -0.0093
Occult Bracelet -0.0108
Dragon Scale -0.0108
Paladin Sword -0.0116
Faded Broach -0.0116
Pupil'S Gift -0.0128
Apex -0.0128
Stygian Desolator -0.0142
Ogre Seal Totem -0.0146
Titan Sliver -0.0153
Grove Bow -0.0168
Ex Machina -0.0182
Tumbler'S Toy -0.0202
Elven Tunic -0.0217
Pirate Hat -0.0223
Lance Of Pursuit -0.0226
Vampire Fangs -0.0241
Philosopher'S Stone -0.0249
Pig Pole -0.0272
Vambrace -0.0302
Spark Of Courage -0.0358
Broom Handle -0.0408
Duelist Gloves -0.0562