Per the paper:
“This investigation is driven by the following intuition: the closer the blocksize is to the limit, the more likely the next transaction will be published on a later block and not the most current one. When these cybercriminals breach a crypto exchange, or ‘close’ a fraudulently operated one, they want to launder the stolen bitcoin quickly.”
The researchers tested their hypothesis by exploiting historical Bitcoin blockchain data and a crypto exchange “scam report.” Using a sample period of 2010 through 2021, they created a “fullness” score for blocks by which to evaluate the data.
After creating a benchmark, the team analyzed historical data for two specific metrics: how much block fullness contributed to the price of Bitcoin (BTC), and how much block fullness acted as a deterrent for bad actors.
Their evaluation, according to the paper, confirmed the team’s hypothesis that “full Bitcoin blocks act as a deterrent to hackers and scammers because they signal congestion.” They also concluded that full blocks “also signal a rise in network security that is captured in price,” thus realizing their second hypothesis that block fullness affected Bitcoin price.
Per the team’s findings, block fullness is cited as 20% lower on the “average day” that has an incidence of a cryptocurrency breach or fraud.