The Rise in House Prices in China: Bubbles or Fundamentals?

The dramatic rise of house prices in many cities of China has brought huge attention from both the governmental and academic circles. There is a huge debate on whether the increasing house prices are driven by market fundamentals or just by speculation. Like Levin and Wright (1997a, 1997b), we decompose house prices in China into fundamental and non-fundamental components. We also consider potential nonlinear feedback from the historical growth rate of house prices on the current house prices and propose a semiparametric approach to estimate the speculative components in the model. We demonstrate that the non-fundamental part contributes a relatively small proportion of the rise of house prices in China.

An extensive study of blazar broad emission line: Changing-look blazars and Baldwin effect

It is known that the blazar jet emissions are dominated by non-thermal radiation while the accretion disk jets are normally dominated by thermal emission. In this work, our aim is to study the connection between the two types of emission by investigating the correlation between the blazar emission line intensity property, which embodies the nature of accretion disk, and the $\gamma$-ray flux property, which is the representative of jet emission. We compiled a sample of 656 blazars with available emission line equivalent widths ($EW$), the GeV $\gamma$-ray flux, and the SED information from the literature. In this work, we found 55 previous BCUs are now identified as FSRQs, and found 52 Changing-look blazars based on their $EW$ and 45 of them are newly confirmed. These Changing-look blazars have a larger accretion ratio (${\dot M}/{\dot M}_{\rm Edd}$) than BL Lac objects. In addition, we suggest that the lower synchrotron peak blazars (LSPs) could be the source of Changing-look blazars because 90.7\% of the Changing-look blazars in this work are confirmed as LSPs. An anti-correlation between $EW$ and continuum intensity, the so-called global Baldwin effect (BEff) has been confirmed. We suggest the steeper global BEff observed for blazar than for radio-quiet active galactic nuclei (RQ-AGNs) is caused by the inverse Compton scattering of broad-emission-line photons. This interpretation is further supported by the positive correlation between the emission line $EW$ and intrinsic inverse Compton luminosity.Comment: Accepted to Ap