Nonlinearity and the permanent effects of recessions

This paper presents a new nonlinear time series model that captures a post-recession “bounce-back” in the level of aggregate output. While a number of studies have examined this type of business cycle asymmetry using recession-based dummy variables and threshold models, we relate the “bounce-back” effect to an endogenously estimated unobservable Markov-switching state variable. When the model is applied to U.S. real GDP, we find that the Markov-switching regimes are closely related to NBER-dated recessions and expansions. Also, the Markov-switching form of nonlinearity is statistically significant and the “bounce-back” effect is large, implying that the permanent effects of recessions are small. Meanwhile, having accounted for the “bounce-back” effect, we find little or no remaining serial correlation in the data, suggesting that our model is sufficient to capture the defining features of U.S. business cycle dynamics. When the model is applied to other countries, we find larger permanent effects of recessions.Business cycles ; Recessions

Implementing a Flexible Approach to Teacher Assignments and Placement of Students with Special Needs: A Policy Advocacy Document

In February 2013, the Illinois State Board of Education (ISBE) informed school districts that they were considering changing the rules related to special education class size and the percentage of students with Individualized Education Plans (IEPs) who can be enrolled in regular education classrooms. As of January 17, 2014, the rules related to special education staffing and the percentage of regular and special education students in classrooms are still pending approval by ISBE (Special Education Today, 2014). The purposes of this project are as follows: to advocate for the maintenance of the current rule while building in some flexibility, to ensure a least restrictive environment with the understanding that no fixed percentage is reasonable, to reflect on situations where severity of student needs demand that students are appropriately educated in an appropriate setting, to maintain current staffing practices, and to retain self-contained special education classes in Grey County School District. All students will continue to receive instruction and support services by highly qualified teachers and other staff. This researcher argues that the special education rules and guidelines in place as of February 2014 should be maintained in order to allow school districts to address the unique needs of their students as well as provide adequate resources and related professional development opportunities

A Bayesian approach to counterfactual analysis of structural change

In this paper, we develop a Bayesian approach to counterfactual analysis of structural change. Contrary to previous analysis based on classical point estimates, this approach provides a straightforward measure of estimation uncertainty for the counterfactual quantity of interest. We apply the Bayesian counterfactual analysis to examine the sources of the volatility reduction in U.S. real GDP growth in the 1980s. Using Blanchard and Quah’s (1989) structural VAR model of output growth and the unemployment rate, we find strong statistical support for the idea that a counterfactual change in the size of structural shocks alone, with no corresponding change in propagation, would have produced the same overall volatility reduction that actually occurred. Looking deeper, we find evidence that a counterfactual change in the size of aggregate supply shocks alone would have generated a larger volatility reduction than a counterfactual change in the size of aggregate demand shocks alone. We show that these results are consistent with a standard monetary VAR, for which counterfactual analysis also suggests the importance of shocks in generating the volatility reduction, but with the counterfactual change in monetary shocks alone generating a small reduction in volatility.Monetary policy ; Econometrics

Why business academics remain in Australian universities despite deteriorating working conditions and reduced job satisfaction : an intellectual puzzle

In the last two decades, Australia\u27s 38 universities have been subjected to profound changes affecting the working lives of their academic staff. That the working conditions of staff have deteriorated cannot be denied, while many studies have shown that job satisfaction has been affected adversely. Paradoxically, there is little evidence that academics are seeking employment outside the university system. In this article, the authors report the findings from their survey of over 3000 academics employed in business disciplines in Australian universities, which aimed to find explanations for this phenomenon.<br /

Preliminary Observations on New Images of the Elysium Frozen Sea Deposits from HRSC Mars Express

Abstract not available

Renormalization Group Analysis of \rho-Meson Properties at Finite Density

We calculate the density dependence of the $\rho$-meson mass and coupling constant($g_{\rho NN}$) for $\rho$-nucleon-nucleon vertex at one loop using the lagrangian where the $\rho$-meson is included as a dynamical gauge boson of a hidden local symmetry. From the condition that thermodynamic potential should not depend on the arbitrary energy scale, renormalization scale, one can construct a renormalization group equation for the thermodynamic potential and argue that the various renormalization group coefficients are functions of the density or temperature. We calculate the $\beta$-function for $\rho$-nucleon-nucleon coupling constant ($g_{\rho NN}$) and $\gamma$-function for $\rho$-meson mass ($\gamma_{m_\rho}$). We found that the $\rho$-meson mass and the coupling constant for $g_{\rho NN}$ drop as density increases in the low energy limit.Comment: 24 pages, 10 figures, revised versio

The Beagle landing site in Isidis Planitia

The Mars probe Beagle 2 will land in Isidis Planitia. This region satisfies the engineering constraints and has evidence for particularly volatile-rich subsoil. Isidis provides a suitable place for the lander to search for H2O and organic matter

Statistical Exploration of Fragmentation Phase Space Source Sizes in Nuclear Multifragmentation

The multiplicity distributions for individual fragment Z values in nuclear multifragmentation are binomial. The extracted maximum value of the multiplicity is found to depend on Z according to m=Z_0/Z, where Z_0 is the source size. This is shown to be a strong indication of statistical coverage of fragmentation phase space. The inferred source sizes coincide with those extracted from the analysis of fixed multiplicity charge distributions.Comment: 13 pages, 4 revised figures, some revised tex