Interpretation of visual scalograms is subjective so it is desirable to find a more quantifiable way to validate the strengthening of coherence in bubble regimes. Fig 6 shows the wavelet coherence over time for the different period bands, in the case of the “new authors” factor for Ethereum. Coherence values, plotted on the vertical axis, vary between zero and one. Time is plotted on the horizontal axis. The areas of the price time series that are recorded as bubble-like regimes using the GSADF test are shaded red.
Developed in 2012 by Toronto-based programmer Vitalik Buterin, and backed by an initial $18 million crowdfund, Ether (ETH) is a cryptocurrency that underpins a blockchain network called Ethereum. While Bitcoin was designed to be a digital currency, Ethereum is a more general implementation of blockchain technology.

Some security tokens are linked to an external tradable asset, and you can feel relatively comfortable assessing them as a more volatile relative of traditional shares, perhaps using a similar framework to the one you’d employ for penny stocks.
“Every single day, the concept that it could be worth something, it could be a store of value is being continually approved by more large, powerful entities,” Johnson says, pointing to established financial institutions holding digital currencies and large corporations adding them to their corporate balance sheets. “The idea that it’s actually worth something is continuing to grow as adoption and acceptance continues to grow as well.”