? Striking Gold in Software Repositories An Econometric Study of - PowerPoint PPT Presentation

? Striking Gold in Software Repositories An Econometric Study of Cryptocurrencies on GitHub Asher Trockman , Rijnard van Tonder, Bogdan Vasilescu MSR ’19, May 26–27, Montréal, QC, Canada

Why do we think there is “gold”? Dabbish et al. 2012, Trockman et al. 2018 Quality Assurance 1.) Visible Signals on GitHub Influence Popularity y t i v i t c Perceptions of Software Quality A Perceived Quality s Kristoufek 2013, 2015; e y r t ε u i c t 2.) “Attractiveness” a i l b e F u P & Crypto Influences Crypto Speculators Attractiveness ε Garcia et al. 2014 Price 3.) Informed? Speculators Drive Price 1

Collecting Crypto Financial & Development Data 347 Days of Daily Measurements 347 Days of Daily Measurements 1.00 Market Cap (Scaled) Financial (Market 0.75 Capitalization) 0.50 0.25 0.00 8 8 8 9 8 1 1 1 1 1 0 0 0 0 0 2 2 2 2 2 n r t n l c p u a a O A J J J 1.00 Total Stars (Scaled) 0x Achain AdEx aelf Aeon Aeron Aeternity Agoras Tokens Agrello Aion ALIS Ambrosus Ark Asch Augur 0.75 Bancor Basic Attention Token Bean Cash Bibox Token Binance Coin Bismuth BitClave Bitcoin Bitcoin …and 239 other cryptocurrencies: Cash Bitcoin Gold BitConnect Bitcore BitShares Blackmoon Blocknet Blocktix BLOCKv Bloom Bodhi Bounty0x Burst Byteball Bytes Bytecoin Bytom Cardano Centra CloakCoin Cobinhood Counterparty Crown 0.50 Cryptonex CyberMiles Dash Decentraland Decision Token Decred DeepOnion Delphy Dentacoin Diamond DigiByte DigitalNote DigixDAO Dimecoin district0x Divi Dogecoin Dragonchain DubaiCoin eBitcoin Development (different availability for different parts of the study) Edgeless Elastic Electra Electroneum Emercoin Enigma Enjin Coin EOS Ethereum Ethereum Classic Etherparty ETHLend Expanse Experience Points Factom FairCoin Feathercoin Flash Game.com Genesis 0.25 Vision Gifto Gnosis Golem Golos Greencoin Grid+ GridCoin Groestlcoin GXShares HempCoin Hshare Activity & Popularity HTMLCOIN Humaniq Hush I/O Coin ICON iExec RLC Ink INS Ecosystem Internet Node Token ION IoT Chain IOTA Kin Komodo Kyber Network Lamden LAToken LBRY Credits LEOcoin Linda Lisk Litecoin Loopring 0.00 Lunyr Lykke MaidSafeCoin Matchpool MediBloc MediShares Melon Mercury Metaverse ETP MinexCoin 8 8 8 9 8 Mintcoin Moeda Loyalty Points MonaCoin Monero MonetaryUnit Monetha Mooncoin Myriad Namecoin NAV 1 1 1 1 1 0 0 0 0 0 2 …and more! 2 2 2 2 2 Coin Neblio Nebulas NEM NEO Neumark Neutron NewYorkCoin Nexus Nimiq NoLimitCoin Nuls Numeraire NVO n r t n l c p u a a OKCash OmiseGO Omni Open Trading Network Oyster Pandacoin Particl Pascal Coin Peercoin Peerplays O A J J J Phore Pillar PIVX Playkey Po.et Populous PotCoin Presearch PRL Pura QLINK Qtum Quantstamp Quantum

Correlation with Avg. Market Cap = (price × coins) Popularity Metrics Quality Assurance Indicators Stars 62% Watchers Badge/CI: F True 61% 10 11 Forks 65% Market Cap 10 9 Activity Metrics Contrib. 50% 10 7 Commits 43% LOC Added 38% Any Badge Any CI LOC Removed 32% (0.22) (0.30) … 3 33% 0% 66%

Linear Models of Avg. Market Cap = (price × coins) Popularity Metrics Quality Assurance Indicators Stars 62% Watchers 61% Forks 65% Contrib. 50% Only popularity metrics are Commits 43% significantly and positively LOC Added 38% associated with avg. market cap. LOC Removed 32% … 3 33% 0% 66%

? Granger “Causality” Metrics ⟺ Market Cap Coin: Bytom ( 1 of ~150 ) 1.00 0.75 Market Cap Similar trends. 0.50 for ~3 coins 0.25 Series 1 0.00 Lagged Series 1 + ε 1.00 Stars Forks Watchers 0.75 Popularity Time 0.50 0.25 0.00 1.00 Commits Added Removed 0.75 Activity 0.50 Past Levels of Past Levels of 0.25 Note: Dependent Independent Dependent 0.00 Jan 2018 Apr 2018 Oct 2018 Jan 2019 Jul 2018 Toda-Yamamoto method Variable Variable Variable 4

? Metrics ⟺ Market Cap Not compelling. Representative example Monero We see evidence of Granger 1.00 No Granger 0.75 Market Cap causality in only a few projects. Causality. 0.50 0.25 Correcting for multiple hypotheses , this is insignificant . 0.00 1.00 Stars Forks Watchers Exclusive! 0.75 Popularity Stars Granger-cause? Market Cap 9/142 coins 0.50 Binance, Cryptonex, Diamond, Electroneum, 0.25 Emercoin, INS Ecosystem, Pandacoin, Vericoin, ZenCash 0.00 1.00 Watchers Granger-cause? Market Cap 4/146 coins Commits Added Removed 0.75 Activity Ark, Mintcoin, NEM, PIVX 0.50 0.25 0.00 Jan 2018 Apr 2018 Oct 2018 Jan 2019 Jul 2018 *(But we are likely to get similar from random noise.) 5

? Metrics ⟺ Market Cap Not compelling. Exceptional example Other models reveal a very ZenCash We see evidence of Granger 1.00 weak connection between Granger causality? 0.75 Market Cap causality in only a few projects. 0.50 popularity and market cap, 0.25 which is not robust . 0.00 1.00 Stars Forks Watchers Exclusive! 0.75 Popularity Stars Granger-cause? Market Cap 9/142 coins 0.50 Binance, Cryptonex, Diamond, Electroneum, 0.25 Emercoin, INS Ecosystem, Pandacoin, Vericoin, ZenCash < Large outlier 0.00 1.00 Watchers Granger-cause? Market Cap 4/146 coins Commits Added Removed 0.75 Activity Ark, Mintcoin, NEM, PIVX 0.50 0.25 0.00 Jan 2018 Apr 2018 Oct 2018 Jan 2019 Jul 2018 *(But we are likely to get similar from random noise.) 6

:-( Looks like we haven’t struck gold. BUT: Long-term: Signals of Pop. & QA Quality Assurance Future work Correlation with Avg. Market Cap = (price × coins) Popularity y t i v Popularity Metrics Quality Assurance i t Multi-year trends Indicators c Stars 62% A Watchers Badge/CI: F True 61% 10 11 Forks 65% Sophisticated models Perceived Market Cap 10 9 Activity Metrics Quality Contrib. 50% 10 7 Volatility or volume Commits 43% LOC Added 38% Any Badge Any CI LOC Removed 32% s (0.22) (0.30) e y r t ε u … i 0% 33% 66% c t a i l Check out e b F u P Short-term: Very limited evidence econometric & Crypto Attractiveness techniques ? Metrics ⟺ Market Cap Not compelling. Representative example for future studies! Monero We see evidence of Granger 1.00 No Granger 0.75 Market Cap causality in only a few projects. Causality. ε 0.50 0.25 Correcting for multiple hypotheses , this is insignificant . 0.00 ? 1.00 Stars Forks Watchers ! e v i s u l c 0.75 x E Popularity Stars Granger-cause? Market Cap 9/142 coins 0.50 Contact Binance, Cryptonex, Diamond, Electroneum, 0.25 Price Emercoin, INS Ecosystem, Pandacoin, Vericoin, ZenCash 0.00 1.00 Watchers Granger-cause? Market Cap 4/146 coins Commits Added Removed 0.75 Activity asher.trockman@gmail.com Ark, Mintcoin, NEM, PIVX 0.50 0.25 0.00 Jan 2018 Apr 2018 Jul 2018 Oct 2018 Jan 2019 *(But we are likely to get similar from random noise.) 7 http://ashertrockman.com