Generating and Sampling Orbits for Lifted Probabilistic Inference

A key goal in the design of probabilistic inference algorithms is identifying and exploiting properties of the distribution that make inference tractable. Lifted inference algorithms identify symmetry as a property that enables efficient inference and seek to scale with the degree of symmetry of a probability model. A limitation of existing exact lifted inference techniques is that they do not apply to non-relational representations like factor graphs. In this work we provide the first example of an exact lifted inference algorithm for arbitrary discrete factor graphs. In addition we describe a lifted Markov-Chain Monte-Carlo algorithm that provably mixes rapidly in the degree of symmetry of the distribution

A New Look at the Forward Premium Puzzle

This paper analyzes the sampling properties of the widely documented large negative slope estimates in regressions of future exchange returns on current forward premium. We argue that the abnormal behavior of the slope estimators in these regressions arises from the simultaneous presence of high persistence, low signal-to-noise ratio, strong endogeneity and an omitted variable problem. The paper develops the limiting theory for the slope parameter estimators in the levels and differenced forward premium regressions under some assumptions that match the empirical properties of the data. The asymptotic results derived in the paper help to reconcile the findings from the levels and difference specifications and provide important insights about the time series properties of the implied risk premium.Forward premium anomaly, high persistence, low signal-to-noise ratio, local-to-unity asymptotics

Demand and productivity components of business cycles: Estimates and implications

Standard stochastic growth models provide theoretical restrictions on output decomposition which can be used to investigate whether productivity shocks played a major role in observed business cycles. Applying these restrictions to US data leads to the following findings: i) Business cycles implied by productivity shocks are mildly correlated to overall fluctuations and help account for a few episodes of US postwar recessions. However, only 20% of US fluctuations can be explained by these shocks. ii) Most fluctuations seem instead to be due to "nominal demand" shocks, i.e. shocks which move output and prices in the same direction, but whose effects on output are ultimately transitory. iii) Canonical sticky price models in the New-Neoclassical Synthesis tradition can account for the cyclical comovements of output and prices, but canonical, frictionless, RBC models cannot.Business cycles, technological shocks, demand shocks

KNOWLEDGE SPILLOVER, LEARNING INCENTIVES AND ECONOMIC GROWTH

Knowledge spillover implies that the social value of knowledge is higher than its private value and leads to insufficient private investment in human capital. This paper examines implications for economic growth and offers a remedy. An incentive mechanism that implements the socially optimal outcome is offered based on learning subsidy and flat income or consumption taxes (each levied at a different phase of the growth process). The scheme is self-financed in that the tax proceeds cover exactly the subsidy payments at each point of time.endogenous growth, human capital, knowledge spillover, learning incentives, linear taxes, International Development, C61, H21, O33, O38, O41,

Absorptive Capacity: More Than the Volume of Aid, its Modalities Matter

We examine whether absorptive capacity represents a valid reason to reject the proposal of a large aid increase in order to help poor countries to move out of the underdevelopment trap. We consider absorptive capacity, the set of limits to an effective use of aid inflows, under for main aspects: 1) disbursement constraints, which lead to under utilisation of credits; 2) macroeconomic troubles, including loss of competitiveness and macroeconomic volatility; 3) decrease of aid returns, actually slower in more vulnerable countries, 4) institutions weakening induced by aid dependency. We argue that these limits to absorptive capacity may be removed by an improvement of aid modalities, such as better balancing between productive and social activities financed by aid, using aid as insurance against exogenous shocks, giving priority in aid allocation to “least developed countries”, which are the most vulnerable, and finally substituting a performance-based conditionality to the traditional-policy based one.Conditionality, volatility, aid effectiveness, absorptive capacity