This paper studies invariance relationships in tick-by-tick transaction data in the U.S. stock market. Over the 1993–2001 period, the estimated monthly regression coefficients of the log of trade arrival rate on the log of trading activity have an almost constant value of 0.666, strikingly...

Using an annual panel of US states over the period 1982-2014, we estimate the response of macroeconomic variables to a shock to the number of new firms (startups). We find that these shocks have significant effects that persist for many years on real GDP, productivity, and population. This...