Evaluating the Rationality of Fixed-event Forecasts

A test of forecast rationality based on the weak efficiency of fixed-event forecasts was proposed by Nordhaus (1987). This paper considers the scope for pooling fixed-event forecasts across ‘events’, to deliver more powerful tests of the weak-efficiency hypothesis, when only a small number of fixed-event forecasts are available. In an empirical illustration we demonstrate the usefulness of this approach. We also suggest an interpretation of the rejection of the null hypothesis of weak efficiency in favour of negative autocorrelation in series of revisions to fixed-event forecasts. The relationship between weak efficiency and rationality when loss functions are asymmetric and prediction error variances are time-varying is also considered.© 1997 John Wiley & Sons, Ltd.     

Diagnosis of Vocal Cord Paralysis in Anaesthesia

Vocal cord paralysis can occur as a complication o surgery or anaesthesia,if permanent is a significant clinica problem.Early detection is important to optimize the chance o repair,and avoid complications associated with an impaired swallow.An algorithm to detect altered vocal cord function was presented based on wavelet packet analysis(WPA) and suppor vector machines(SVM),and compared with the Hoarseness Diagram method(HDm),which was reported as an objective voice quality evaluation approach and could be u...     

Short-term climatic impacts of afforestation in the East Asian monsoon region

The influence of changes in vegetation cover on short-term climate over the East Asian monsoon region is simulated using the Community Climate System Model Version 3.5.The results show the annual mean surface air temperature significantly decreases by 0.93°C in response to afforestation over the East Asian monsoon region.Also,surface air temperature decreases by 1.46 and 0.40°C in summer and winter,respectively.The cooling is caused by enhanced evapotranspiration(ET) produced by increased forest cover.Evapotranspiration is greater in summer than in winter,so summer cooling is greater than winter cooling.The annual mean precipitation increases in response to afforestation,with a maximum of 7% in April.Water vapor increases significantly because of greater latent heat flux release.Meanwhile,afforestation leads to higher surface roughness,which decreases surface wind speed and induces an ascending air motion.These factors can produce more clouds and precipitation.Moreover,the surface albedo and the reflective solar radiation are reduced in response to afforestation.