From the study:
"We study this correlation empirically by collecting data on the pricing of the largest 50 ICOs and test whether the behaviour of ICO returns are correlated to the returns of Bitcoin and Ethereum. If ICOs are truly pricing their unique business models, we would expect their returns to be idiosyncratic with low correlations. If, on the other hand, they are simply seen as an investment vehicle to generate excess returns based on a ‘cryptocurrency bubble’, we would expect them to be highly correlated to prices of the major cryptocurrencies."
"Correlations remained positive but low while the cryptocurrency phenomenon was taking off and Bitcoin and Ethereum prices were increasing. However, once the price of the two cryptocurrencies starts falling, correlations increase and reach a very high level, signalling that daily news on the future of Bitcoin and Ethereum seems to be moving the price of all ICO tokens. It seems that as the ‘cryptocurrency bubble’ bursts, the price-discovery mechanism of ICOs collapses and all their prices just track the value of Bitcoin or Ethereum."