Choice of Portfolios and Fee under Principal -Agent Framework with Uncertain Exit - Time

In the real world, an investor is usually not sure about when he or she will exit investment. She can only make estimation prior. With the growth of the scale of open - end funds which can be subscribed and redeemed at any time. Investors began to pay more attention on problems such as whether the fee is reasonable, the payment can encourage the agent or not. Others would consider if the portfolio that the agent chooses is the best one. This paper considers the principal - agent problem with uncertain exit - time under two cases： the action of the agent is observable and unobservable. We derive close - form expressions of the optimal portfolio and the best fee. Finally an empirical analysis is given based on the data of some open - end funds in China.     

WHAT IS THE EFFECT OF HOUSEWORK ON THE MARKET WAGE,AND CAN IT EXPLAIN THE GENDER WAGE GAP?

Abstract Does housework reduce the market wage, and if so, does it have a similar impact for males and females? In this paper, we survey and evaluate the recent and growing empirical literature on the linkages between housework and the wage rate. The review is motivated by unexplained gender wage gaps across studies, which consider personal and market‐related factors. We focus on this less‐studied aspect of wage determination. We consider the required modelling framework, and provide standardized estimated effects of housework on the hourly wage across studies. We evaluate how this literature has addressed potential estimation problems, in particular, the endogeneity of housework, concavity of the housework–wage function, threshold effects and work effort effects. We conclude that the evidence across ordinary least squares, instrumental variable, fixed effects and two‐stage least squares results casts serious doubt on the idea that the negative female housework–wage relationship is only driven by endogeneity bias or individual‐specific characteristics. Yet, much more needs to be done to address modelling and data requirements, and we point out likely and promising future research directions.     

A nonlinear long memory model, with an application to US unemployment

Two important empirical features of US unemployment are that shocks to the series seem rather persistent and that it seems to rise faster during recessions than that it falls during expansions. To jointly capture these features of long memory and nonlinearity, we put forward a new time series model and evaluate its empirical performance. We find that the model describes the data rather well and that it outperforms related competitive models on various measures of fit.     

论税收的时效性

时效性是税收强制性在时间上的体现，是税法赋予的一种规定性，是国家财政收支及时稳定的重要保证，是依法治税的必然要求，是衡量税务机关征管水平的基本依据。不论是税收法治的严肃性，还是国家各项事业急需财政资金的现实，都迫切需求提高税收的时效性。及时有效地组织好财政收入。     

A note on the Robust Trend and ARARMA methodologies used in the M3 Competition

This brief note describes two of the forecasting methods used in the M3 Competition, Robust Trend and ARARMA. The origins of these methods are very different. Robust Trend was introduced to model the special features of some telecommunications time series. It was subsequently found to be competitive with Holt’s linear model for the more varied set of time series used in the M1 Competition. The ARARMA methodology was proposed by Parzen as a general time series modelling procedure, and can be thought of as an alternative to the ARIMA methodology of Box and Jenkins. This method was used in the M1 Competition and achieved the lowest mean absolute percentage error for longer forecasting horizons. These methods will be described in more detail and some comments on their use in the M3 Competition conclude this note.     

Mean squared error of the empirical best linear unbiased predictor in an orthogonal finite discrete spectrum linear regression model

The mean squared error (MSE) of the empirical best linear unbiased predictor in an orthogonal finite discrete spectrum linear regression model is derived and a comparison with the MSE of the best linear unbiased predictor in this model is made. It is shown that under weak conditions these two mean square errors are asymptotically the same.     

The asymmetry of judgemental confidence intervals in time series forecasting

In forecasting a time series, one may be asked to communicate the likely distribution of the future actual value, often expressed as a confidence interval. Whilst the accuracy (calibration) of these intervals has dominated most studies to date, this paper is concerned with other possible characteristics of the intervals. It reports a study in which the prevalence and determinants of the symmetry of judgemental confidence intervals in time series forecasting was examined. Most prior work has assumed that this interval is symmetrically placed around the forecast. However, this study shows that people generally estimate asymmetric confidence intervals where the forecast is not the midpoint of the estimated interval. Many of these intervals are grossly asymmetric. Results indicate that the placement of the forecast in relation to the last actual value of a time series is a major determinant of the direction and size of the asymmetry.     

Distance in time between transition economies and the European Union

The time distance methodology used offers a new perspective to the problem, an additional statistical measure, and a presentation tool for policy analysis and debate readily understood by policy makers, media and general public. Disparity between the analysed transition economies and EU countries is considerably smaller for other indicators than for GDP per capita. Compared with Ireland, Portugal and Greece Slovenia was in 1995 in 13 cases behind (but time lag of Slovenia never exceeded 10 years) and in 13 cases ahead of them. Sicherl (1997a) discusses application of S-distance to time series regressions, models, forecasting and monitoring. First version received: October 1995/final version received: April 1998     

评审专家抽取中的时间距离约束分析

针对现有评审专家抽取中距离约束存在的不足,本文提出了一种新的时间距离约束。本文介绍了时间距离的含义及其提出的必要性,并给出了基于GIS技术的时间距离计算方法,具体包括相关假设、计算步骤、解决方案以及实现过程。时间距离约束的提出不仅可以保证所有被选专家都可按时到达评审地点,而且还能打破行政区域的限制,合理调配专家资源,具有重要的现实意义。     

一种利用短时DFT分析实现全数字2DPSK接收机解调的新算法

本文提出了一种简单而实用的利用短时DFT（ST-DFT）分析实现全数字2DPSK接收机的解调算法。该算法对由多谱勒效应引起的时变频率漂移具有鲁棒性。由于该算法是通过检测在载频处的瞬时能量谱的跳变来实现2DPSK信号的解调，所以该算法不需要进行专门的载波相位恢复、符号定时，且具有较好的抗噪性能，实现起来简单。