Publications

Résumé In a similar way to the stock market, the housing market in China has often been portrayed as highly speculative, giving rise to “bubble” concerns. Over the last decade, residential prices increased every year on average by double digits in Beijing or Shanghai. However many observers and researchers argue that fundamentals of the housing sector, both sector-specific and macroeconomic, may have been the driving force behind housing price volatility. While existing empirical work exclusively relies on the government housing prices which may suffer from the well-documented downward bias, this paper uses original high frequency unit price as well as transaction series for the residential resale housing markets of Beijing and Shanghai between January 2005 and December 2010 to test alternative hypotheses about housing prices volatility.
Mots clés MIDAS, Conditional variance, Bubbles, China, Housing prices
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Résumé A general way to study the extremes of a random variable is to consider the family of its Wang distortion risk measures. This class of risk measures encompasses several popular indicators such as the classical quantile/Value-at-Risk, the Tail-Value-at-Risk and the recently introduced Conditional Tail Moments, among others. A couple of very recent studies have focused on the estimation of extreme analogues of such quantities. In this paper, we consider trimmed and winsorised versions of the empirical counterparts of extreme Wang distortion risk measures. We analyse their asymptotic properties, and we show that we can construct bias-corrected trimmed or winsorised estimators of extreme Wang distortion risk measures who appear to perform overall better than their standard empirical counterparts in practice when the underlying distribution has a very heavy right tail. We also showcase our technique on a set of real fire insurance data.
Mots clés Heavy-Tailed Distribution, Extreme value statistics, Asymptotic Normality, Wang distortion risk measure, Trimming, Winsorising
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Résumé We introduce and examine an inexact multi-objective proximal method with a proximal distance as the perturbation term. Our algorithm utilizes a local search descent process that eventually reaches a weak Pareto optimum of a multi-objective function, whose components are the maxima of continuously differentiable functions. Our algorithm gives a new formulation and resolution of the following important distributive justice problem in the context of group dynamics: In each period, if a group creates a cake, the problem is, for each member, to get a high enough share of this cake; if this is not possible, then it is better to quit, breaking the stability of the group.
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Résumé This paper shows the uneven role played in the inflation dynamics of African franc zone countries by their integration in a regional monetary union. We obtain three main results sharply contrasting the central- (CEMAC) and west-African (WAEMU) regions. First, differences in the structure of economies and national fiscal stances play a similar role in both unions and appear as potential sources of inflation differentials. Second, even though co-movements are the principal drivers of inflation dynamics in both subregions, global factors dominate regional ones in WAEMU while both play an equal role in CEMAC. Thirdly, spatial interactions are unimportant in CEMAC due to little intra-zone trade, but take an asymmetric form in WAEMU due to the large size of Ivory Coast and Senegal.
Mots clés Inflation, Common factor models, Spatial dependence, Franc-zone
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Résumé In this paper, we study how rents are shared between capital and labour, using industry†level panel data for 19 OECD countries from 1988 through to 2007. The first step is an explanation of the rent†creation process. We provide evidence of a significant impact of regulation on value†added prices at the industry level relative to the value†added price for the overall economy (rent). In the second step, we dissect the value†added sharing process. By running ordinary least†squares and instrumental variables estimations, we obtain results that confirm the Blanchard–Giavazzi prediction: the impact of rents on the capital share depends on workers' bargaining power.
Mots clés Capital share, Market regulations, Output gap, Prices, Rents, Unemployment
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Résumé After years of high commodity prices, a new era of lower ones, especially for oil, seems likely to persist. This will be challenging for resource-rich countries, which must cope with the decline in income that accompanies the lower prices and the potential widening of internal and external imbalances. This column presents a new VOXEU eBook in which leading economists from academia and the public and private sector examine the shifting landscape in commodity markets and look at the exchange rate, monetary, and fiscal options policymakers have, as well as the role of finance, including sovereign wealth funds, and diversification.
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Résumé This paper investigates whether trading volume and price distortion can be explained by the investor’s bounded rationality. Assuming that agents are bounded by their information access and processing, what are the consequences on market dynamics? We expose the result of simulations in an ABM that considers the liquidity as an endogenous characteristic of the market and allows to design investors as bounded rational. In a call auction market, where two risky assets are exchanged, traders are defined as a mix between fundamentalist and trend-follower outlook. Each one differs as to behaviour, order-placement strategy, mood, knowledge, risk-aversion and investment horizon. We place agents in a context of evolving fundamental values and order placement strategy; they perceive the fundamental but they also have some heterogeneous belief perseverance; and they adapt their orders to the market depth so as to maximise their execution probability and their profit. By adding bounded rationality in their information processing, we show that (1) usual features as trend-follower outlook and heterogeneous investment horizon are important features to generate excess volatility of asset prices and market inefficiency; (2) the learning fundamental value stabilises the market price and the trading volume; (3) the order-placement strategy increases trading volume, but reduces market efficiency and stability; (4) the agent’s mood prevents illiquid market and weakly increases the market volatility as classical noise trader agents; (5) the impatience to sell of traders is always present in the market: the market sell orders are always more numerous than the market buy orders.
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Résumé BACKGROUND: Dementia is a prevalent condition, affecting 5-7% of people aged 60 years and older, and a leading cause of disability in people aged 60 years and older globally. We aimed to examine the association between alcohol use disorders and dementia risk, with an emphasis on early-onset dementia (1·7) in sensitivity analyses on dementia case definition (including Alzheimer's disease) or older study populations. Also, alcohol use disorders were significantly associated with all other risk factors for dementia onset (all p
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Résumé This article analyzes the impacts of Environmental Tax Reform (ETR) when the government is constrained not to increase the public debt-to-output ratio. We consider an overlapping generations model with pollution. Public spending for pollution abatement are financed by tax revenues and public debt. We show that keeping constant the public debt-output ratio is not an obstacle to attain a double dividend, i.e. an increase of both (i) environmental quality and (ii) aggregate consumption. First, if the capital stock is low and the pollution abatement is large enough, a successful ETR consists in a rise of the environmental tax, compensated by a decrease of the income tax. Secondly, we show that the environmental tax revenues may help reduce the public debt-output ratio. We give conditions (on the initial level of the environmental tax and the debt-output ratio) such that an increase of the environmental tax, budget-balanced by a decrease of the debt-output ratio may also achieve a double dividend. We conclude that public debt crisis should not compromise ETR, instead, environmental tax revenues could be part of the solution. JEL: Q5, H23, H63 / KEY WORDS: Environmental Tax Reform, Debt, Public Emission Abatement, Double Dividend, Overlapping Generations Model
Mots clés Environmental Tax Reform, Debt, Public Emission Abatement, Double Dividend, Overlapping Generations Model
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