无穷维系统关于有界控制的零可控性

本文研究自反Bahach空间中线性系统的零可控性。给出了关于有界控制的精确可控性的必要条件和近似可控性的充分必要条件。     

Some evidence concerning the value hypothesis of intergenerational status transmission: A research note

This paper reports some evidence bearing on the value hypothesis of intergenerational status transmission. The point of departure is the studies of Kohn (1969, Class and Conformity: A Study in Values, Dorsey, Homewood, Ill.) and Wright and Wright (1976, American Sociological Review, 41, 527–537) on the social class related value orientations called “self-direction” and “conformity.” Our research examines whether children's valuations along this dimension are associated with the valuations of their parents, as the value hypothesis would argue. Key associations consistent with the hypothesis are found although there is, overall, considerable variation in children's valuations not related to variation in the valuations of their parents. Implications of the finding for future examination of the value hypothesis are discussed.     

Honesty or dishonesty of taxpayer communications in an enforcement regime

In many settings the true likelihood of capture when engaging in an illegal activity, such as tax evasion, is not well known to an individual. “Official” statements from the tax administration regarding enforcement effort provide some information. In addition, “informal”, or “unofficial”, communication among taxpayers can supplement these official announcements, but individuals do not know with certainty whether such unofficial information is honest (or accurate) versus dishonest (or inaccurate). We examine the truthfulness of an individual’s revelation of unofficial information to other individuals, along with the factors that affect any revelation, focusing on the intrinsic motivations for revelations. Our experimental design allows us to examine the type and the honesty of messages that an individual chooses to send to other individuals regarding their own audit outcome and their own compliance behavior. Our results indicate that most individuals send accurate messages about their own audit outcomes and their own compliance behaviors. Nevertheless, many individuals are also systematically dishonest about being audited; that is, we observe a significant tendency for individuals to claim that they were audited when they were not. We also observe a strong interaction between individuals’ audit outcomes and their compliance behaviors, so that individuals who engaged in tax evasion and who were audited were more truthful in their communications than those whose tax evasion went undetected.     

The impact of Oportunidades on human capital and income distribution in Mexico: A top-down/bottom-up approach

To analyze the effects of the Mexican Oportunidades conditional cash transfer program on school attendance and household income distribution, this paper links a microeconometric simulation model and a general equilibrium model in a bidirectional way, so to explicitly take spillover effects of the program into account. Our results suggest that partial equilibrium analysis alone underestimates the distributional effects of the program. Extending the coverage of the program to the poor increases school attendance, reduces child labor supply, and increases the equilibrium wages of children who remain at work. With a relatively low fiscal cost, Mexican social policy could further reduce income inequality and poverty.     

Fiscal policy analysis in the euro area: Expanding the toolkit

The absence of historical quarterly fiscal data has limited the analysis of the macroeconomic impact of fiscal policies in the euro area, including the interactions of fiscal and monetary policies. To overcome this gap, we construct a quite disaggregated euro area quarterly fiscal database for the period 1980Q1–2012Q4, based on a rich set of input fiscal data taken from national sources. We discuss how this dataset has allowed and can allow the profession to tackle new policy-relevant research topics. We also provide stylized facts on the cyclical properties of main euro area fiscal aggregates, focusing on the recent economic crisis period.     

Because of you I did not give up – Peer effects in perseverance

It has been shown that both perseverance as well as peer effects affect performance. In our experiment, we investigate the interplay between these two factors. Participants work on a wordplay task where we quantify perseverance as the decision to continue working hard in the face of challenges. We find that persevering on the task is significantly correlated with the psychological questionnaire measure of grit (Duckworth et al., 2007). In an additional treatment, we provide participants with information about a peer’s contemporaneous perseverance on the task. This significantly increases participants’ perseverance on the task independently of their perseverance as measured in the questionnaire, suggesting that it does not only depend on individuals’ inherent traits, but can also be increased by peers.     

基于单片机控制的编织袋折边折角装置设计

为提高编织袋折边折角的自动化水平和效率，更好地与编织袋缝纫工序结合起来，文章设计了基于单片机控制的编织袋折边折角装置.首先利用Pro/E 4.0设计了编织袋折边折角装置的机械结构三维模型，然后在Microsoft Office Visio中设计了该设备的气动系统，最后利用AT89C51单片机对该套设备进行设计与控制.结果表明，这套编织袋折边折角装置结构紧凑合理，成本控制在1万多元，单片机控制系统稳定有效，整个折边折角动作耗时在6 s左右，效率较高，能够真正提高编织袋折边折角自动化水平，具有很高的工程实践价值.     

On the behavioural relevance of optional and mandatory impure public goods

Impure public goods combine a private good with a public good. Often, impure public goods have a charitable or ethical dimension, giving ethically motivated consumers a convenient option to contribute to public goods through the marketplace (in addition to direct donations). Impure public goods could potentially promote ethical giving or alternatively hinder charitable behaviour. We implement an economics experiment with a between-subject design to test the behavioural relevance of impure public goods with only a token (i.e. small) contribution to a public good. Contributions to the public good are negatively affected by the presence of impure public goods with token contributions. We explore one mechanism to offset this negative impact by making the token impure public good mandatory. We observe higher average contributions and several positive impacts on charitable behaviour, which supports the claim that this mechanism can potentially offset the negative impact of impure public goods.     

How income and tax rates provoke cheating – An experimental investigation of tax morale

Anecdotal evidence suggests that tax morale diminishes with income and with levels of taxation. We designed an experiment that enables identification of causal effects. Subjects carry out a sequence of real effort tasks. The income earned varies with individual differences in effort (combined with variances related to skill or luck) and with the exogenously given length of the tasks. For each task, subjects privately roll a die, whose value determines the tax rate, which is then reported by subjects. This provides subjects with an incentive to cheat. Tax morale diminishes with higher effort, which might find ethical justification, but also with longer tasks, which would not. We implement treatments that vary the range of taxation. Contrary to widespread belief, participants’ tax morale is invariant to these treatments. Our findings are best explained by a psychological force that tempts rich people to cheat more. This force does not seem to be related to fairness ideals that are prominent in theories of distributional justice nor to absolute levels of taxation.