Global Attractivity of a Circadian Pacemaker Model in a Periodic Environment

In this paper, we propose a delay differential equation with continuous periodic parameters to model the circadian pacemaker in a periodic environment. First, we show the existence of a positive periodic solution by using the theory of coincidence degree. Then we establish the global attractivity of the periodic solution under two su±cient conditions. These conditions are easily verifiable and are independent of each other. Some numerical simulations are also performed to demonstrate the main results

The Predictability of REIT Returns and Market Segmentatio

Recent research suggests that real estate returns are more predictable than the returns of other assets and that the real estate market is segmented from the general stock market. This study examines these two issues empirically using a multifactor asset pricing model that allows for time-varying risk premiums. The results indicate that, in a general two-factor asset pricing framework, the REIT market is integrated with the general stock market. Furthermore, no evidence can be found that REIT returns are more predictable than the returns of other stocks.