There is no correlation between Cost and Pick Rate. Some has higher Cost, some has higher Pick Rate. Objects are grouped into clusters (marked with different colors) based on close values of Cost and Pick Rate.
Cost Pick Rate
Abyssal Blade 6325 0.0308
Aghanim'S Blessing 5800 0.0000
Arcane Blink 6800 0.0009
Assault Cuirass 5125 0.0295
Battle Fury 4130 0.0351
Bloodstone 4400 0.0097
Bloodthorn 6500 0.0128
Boots Of Bearing 4125 0.0167
Boots Of Travel 2 4500 0.0072
Butterfly 4975 0.0323
Crimson Guard 3600 0.0328
Daedalus 5150 0.0484
Dagon (2) 4000 0.0018
Dagon (3) 5150 0.0021
Dagon (4) 6300 0.0019
Dagon (5) 7450 0.0134
Desolator 3500 0.0536
Disperser 5700 0.0085
Eternal Shroud 3300 0.0093
Ethereal Blade 4650 0.0236
Eye Of Skadi 5300 0.0446
Gleipnir 6150 0.0313
Guardian Greaves 5050 0.0422
Harpoon 4500 0.0294
Heart Of Tarrasque 5000 0.0433
Heaven'S Halberd 3550 0.0223
Helm Of The Overlord 6400 0.0014
Hurricane Pike 4450 0.0499
Kaya And Sange 4100 0.0294
Linken'S Sphere 4600 0.0355
Lotus Orb 3850 0.0241
Manta Style 4600 0.0735
Mjollnir 5500 0.0264
Monkey King Bar 4975 0.0380
Moon Shard 4000 0.0116
Nullifier 4725 0.0099
Octarine Core 4600 0.0318
Orchid Malevolence 3475 0.0140
Overwhelming Blink 6800 0.0200
Pipe Of Insight 3375 0.0327
Radiance 5050 0.0251
Refresher Orb 5000 0.0138
Revenant'S Brooch 6200 0.0035
Sange And Yasha 4100 0.0196
Satanic 5050 0.0203
Scythe Of Vyse 5550 0.0308
Shiva'S Guard 4850 0.0206
Silver Edge 5300 0.0514
Swift Blink 6800 0.0082
Wind Waker 6825 0.0058
Yasha And Kaya 4100 0.0064
Cost Pick Rate
Aeon Disk 3000 0.0240
Aether Lens 2275 0.0853
Arcane Boots 1300 0.1151
Armlet Of Mordiggian 2475 0.0122
Blade Mail 2100 0.0605
Boots Of Travel 2500 0.0697
Bottle 675 0.0588
Bracer 505 0.0721
Crystalys 1950 0.0206
Dagon 2850 0.0028
Diffusal Blade 2500 0.0388
Dragon Lance 1900 0.0293
Drum Of Endurance 1700 0.0049
Echo Sabre 2500 0.0312
Eul'S Scepter Of Divinity 2725 0.0290
Falcon Blade 1125 0.0113
Force Staff 2200 0.0743
Glimmer Cape 2150 0.0554
Hand Of Midas 2200 0.0389
Helm Of The Dominator 2625 0.0004
Holy Locket 2400 0.0059
Maelstrom 2700 0.0349
Mage Slayer 2500 0.0044
Mask Of Madness 1775 0.0215
Medallion Of Courage 1025 0.0017
Mekansm 1775 0.0096
Meteor Hammer 2400 0.0095
Null Talisman 505 0.0528
Orb Of Corrosion 925 0.0190
Pavise 1400 0.0128
Phase Boots 1500 0.1186
Phylactery 2375 0.0233
Rod Of Atos 2750 0.0208
Shadow Blade 3000 0.0206
Skull Basher 2875 0.0331
Solar Crest 2425 0.0122
Soul Ring 855 0.0239
Spirit Vessel 2980 0.0184
Tranquil Boots 925 0.0812
Urn Of Shadows 880 0.0115
Vanguard 1700 0.0376
Veil Of Discord 1525 0.0080
Vladmir'S Offering 2450 0.0034
Witch Blade 2600 0.0206
Wraith Band 505 0.0919
Cost Pick Rate
Aghanim'S Scepter 4200 0.2229
Aghanim'S Shard 1400 0.3419
Black King Bar 4050 0.1594
Blink Dagger 2250 0.1715
Magic Wand 450 0.2327
Power Treads 1400 0.2368