Demand volatility and the lag between the growth of temporary and permanent employment

"The growth rate of temporary help service employment is often considered to be a leading business cycle indicator, because the firing and hiring of temporary help workers typically lead that of permanent workers. However, few works in the literature focus on the mechanism that generates the lag between temporary and permanent growth. This paper investigates how demand volatility is related to the lag. Focusing on the relationship between a firm's information extraction and their hiring/firing decisions, our simple model predicts that the average size of transitory demand shocks increase the lag while the average size of shocks that persist longer shortens the lag. Our empirical analysis based on cross-city variation finds supporting evidence to the above predictions, after controlling for city size and other city-specific demographic characteristics"--Federal Reserve Bank of Chicago web site.