Optimal Remote State Estimation for Self-Propelled Particle Models

We investigate the design of a remote state estimation system for a self-propelled particle (SPP). Our framework consists of a sensing unit that accesses the full state of the SPP and an estimator that is remotely located from the sensing unit. The sensing unit must pay a cost when it chooses to transmit information on the state of the SPP to the estimator; and the estimator computes the best estimate of the state of the SPP based on received information. In this paper, we provide methods to design transmission policies and estimation rules for the sensing unit and estimator, respectively, that are optimal for a given cost functional that combines state estimation distortion and communication costs. We consider two notions of optimality: joint optimality and person-by-person optimality. Our main results show the existence of a jointly optimal solution and describe an iterative procedure to find a person-by-person optimal solution. In addition, we explain how the remote estimation scheme can be applied to tracking of animal movements over a costly communication link. We also provide experimental results to show the effectiveness of the scheme.Comment: a part of the article was submitted to IEEE Conference on Decision and Control 201

The Impact of Interest-rate Subsidies on Long-term Household Debt: Evidence from a Large Program

The responsiveness of long-term household debt to the interest rate is a crucial parameter for assessing the effectiveness of public policies aimed at promoting specific types of saving. This paper estimates the effect of a reform of Credito Bonificado, a large program in Portugal that subsidized mortgage interest rates, on long-term household debt. The reform established a ceiling in the price of the house that could be financed through the program, and provides plausibly exogenous variation in incentives. Using a unique dataset of matched household survey data and administrative records of debt, we document a large decrease in the probability of signing a new loan after the removal of the subsidy.

The Analysis of Seasonal Return Anomalies in the Portuguese Stock Market

This paper assesses the existence of persistent seasonal effects in the daily returns of the Portuguese stock market. We use daily data on the stock market index to study long-lasting differences in returns across the days of the week, within months and around holidays. For the period 1988-2001, we find no evidence that daily returns are different between weekdays. However, we find a closed-market effect during 1988-1996. This effect disappears for the 1997-2001 period which coincides with the period from when the Portuguese market started to be internationally considered as a developed market.