592 research outputs found
Estimating ordered categorical variables using panel data: a generalized ordered probit model with an autofit procedure
Estimation procedures for ordered categories usually assume that the estimated coefficients of independent variables do not vary between the categories (parallel-lines assumption). This view neglects possible heterogeneous effects of some explaining factors. This paper describes the use of an autofit option for identifying variables that meet the parallel-lines assumption when estimating random effects generalized ordered probit model. We combine the test procedure developed by Richard Williams (gologit2) with the random effects estimation command regoprob by Stefan Boes.Generalized ordered probit; panel data; autofit, self-assessed health.
Estimating ordered categorical variables using panel data: a generalized ordered probit model with an autofit procedure
Estimation procedures for ordered categories usually assume that the estimated coefficients of independent variables do not vary between the categories (parallel-lines assumption). This view neglects possible heterogeneous effects of some explaining factors. This paper describes the use of an autofit option for identifying variables that meet the parallel-lines assumption when estimating a random effects generalized ordered probit model. We combine the test procedure developed by Richard Williams (gologit2) with the random effects estimation command regoprob by Stefan Boes.generalized ordered probit; panel data; autofit, self-assessed health
I feel good! Gender differences and reporting heterogeneity in self-assessed health
For empirical analysis and policy-oriented recommendation, the precise measurement of individual health or well-being is essential. The problem with variables based on questionnaires such as self-assessed health is that the answer may depend on individual reporting behaviour. Moreover, if individualâs health perception varies with certain attitudes of the respondent reporting heterogenei-ty may lead to index or cut-point shifts of the health distribution, causing estimation problems. We analyse the reporting behaviour of individuals on their self-assessed health status, a five-point categorical variable. We explore observed heterogeneity in categorical variables and include unob-served individual heterogeneity using German panel data. Estimation results show different im-pacts of socioeconomic and health related variables on the five subscales of self-assessed health. Moreover, the answering behaviour varies between female and male respondents, pointing to gen-der specific perception and assessment of diseases. Reporting behaviour on self-assessed health questions in surveys is problematic due to a possible heterogeneity. Hence, in case of reporting heterogeneity, using self-assessed measures in empirical studies may be misleading or at least ambiguous.reporting heterogeneity, generalized ordered probit, self-assessed health
Spinning Strings, Black Holes and Stable Closed Timelike Geodesics
The existence and stability under linear perturbation of closed timelike
curves in the spacetime associated to Schwarzschild black hole pierced by a
spinning string are studied. Due to the superposition of the black hole, we
find that the spinning string spacetime is deformed in such a way to allow the
existence of closed timelike geodesics.Comment: 5 pages, RevTex4, some corrections and new material adde
Exploring the Possibilities: Earth and Space Science Missions in the Context of Exploration
According to Dr. Edward J. Weiler, Director of the Goddard Space Flight Center, "Exploration without science is tourism". At the American Astronautical Society's 43rd Annual Robert H. Goddard Memorial Symposium it was quite apparent to all that NASA's current Exploration Initiative is tightly coupled to multiple scientific initiatives: exploration will enable new science and science will enable exploration. NASA's Science Mission Directorate plans to develop priority science missions that deliver science that is vital, compelling and urgent. This paper will discuss the theme of the Goddard Memorial Symposium that science plays a key role in exploration. It will summarize the key scientific questions and some of the space and Earth science missions proposed to answer them, including the Mars and Lunar Exploration Programs, the Beyond Einstein and Navigator Programs, and the Earth-Sun System missions. It will also discuss some of the key technologies that will enable these missions, including the latest in instruments and sensors, large space optical system technologies and optical communications, and briefly discuss developments and achievements since the Symposium. Throughout history, humans have made the biggest scientific discoveries by visiting unknown territories; by going to the Moon and other planets and by seeking out habitable words, NASA is continuing humanity's quest for scientific knowledge
POLICY REVIEW: Freedom of Contract and the Remedy of Forced Hiring: A Comparative Assessment of German and American Anti-Discrimination Law
POLICY REVIEW: Freedom of Contract and the Remedy of Forced Hiring: A Comparative Assessment of German and American Anti-Discrimination Law
Eine Neubewertung des Erdbebens vom 3. September 1770 bei Alfhausen (Niedersachsen)
Am 3. September 1770 fand bei Alfhausen im westlichen Niedersachsen ein Erdbeben statt. In der wissenschaftlichen Literatur wird es erstmals von SIEBERG(1940) erwĂ€hnt. Eine erste AbschĂ€tzung seiner MaximalintensitĂ€t erfolgte durch AHoRNERu. a. (1970) mit I = VII (MSK). Danach wĂŒrde das Erdbeben von Alfhausen zu den stĂ€rksten nachweisbaren seismischen Ereignissen im Norddeutschen Tiefland gehören. SIEBERG,der Ausgangspunkt fĂŒr bisherige IntensitĂ€tsabschĂ€tzungen ist, gibt ĂŒber die Herkunft der Quellen, die seiner Information zugrunde liegen, keine Auskunft. MEIER& GRĂNTHALfanden ein zeitgenössisches Dokument, das kurze Zeit nach dem Ereignis vom 3. September 1770 niedergeschrieben und am 3. November 1770 in: "NĂŒtzlicher Beylagen zum OsnabrĂŒckischen Intelligenz Blate" veröffentlicht wurde. Der Autor unterzeichnete seinen Artikel mit den Initialen J. H. B. P. (P in Antiqua), die mit Hilfe des NiedersĂ€chsischen Staatsarchivs in OsnabrĂŒck als J. H. BUCK,evangelischer Pastor von Neuenkirchen, identifiziert werden konnten. Die Aufzeichnungen von BUCKenthalten eine recht genaue Beschreibung der makroseismischen Erscheinungen des Alfhausen-Ereignisses. Ihre Analyse erlaubt, eine Neubewertung dieses Erdbebens und ermöglicht, die Angaben von SIEBERG(1940) und die darauf fuĂenden nachfolgenden AbschĂ€tzungen zu ĂŒberprĂŒfen. Die Ergebnisse der Analyse werden mitgeteilt, der seismologische Befund in den regionalgeologischen Rahmen eingeordnet und die mögliche Ursache fĂŒr das Beben kurz dargestellt
Individual and Firm Behavior in Health Care Markets : Abstracts of the 10th DIBOGS-Workshop, Bielefeld 2015
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