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Unknown Point (unknown + point)

Distribution by Scientific Domains
Mathematics and Statistics40%

Selected Abstracts

FURTHER COMMENTS ON STATIONARITY TESTS IN SERIES WITH STRUCTURAL BREAKS AT UNKNOWN POINTS

JOURNAL OF TIME SERIES ANALYSIS, Issue 2 2003
Fabio Busetti
First page of article [source]

Individual differences in cooperation in a circular public goods game

EUROPEAN JOURNAL OF PERSONALITY, Issue S1 2001
Robert Kurzban
Research using the public goods game to examine behaviour in the context of social dilemmas has repeatedly shown substantial individual differences in patterns of contributions to the public good. We present here a new method specifically designed to capture this heterogeneity in play and classify participants into broad categories or types. Players in groups of four made initial, simultaneous contributions to the public good. Subsequently, players were sequentially told the current aggregate contribution to the public good and allowed to change their decision based on this information. The game continued, with players updating their contribution decision until the game ended at an unknown point. By looking at the relationship between players' contributions and the aggregate value they observed, we were able to cleanly classify 82% of our players into three types: strong free riders (28%), conditional cooperators of reciprocators (29%), and strong cooperators (25%). We also found that scores on some of the personality dimensions we investigated (self-monitoring, self-esteem, neuroticism, and conscientiousness) correlated with player type. Finally, males were found to be more likely to be strong cooperators than females. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Tests for an Epidemic Change in a Sequence of Exponentially Distributed Random Variables

BIOMETRICAL JOURNAL, Issue 8 2003
Asoka Ramanayake
Abstract Consider a sequence of independent exponential random variables that is susceptible to a change in the means. We would like to test whether the means have been subjected to an epidemic change after an unknown point, for an unknown duration in the sequence. The likelihood ratio statistic and a likelihood ratio type statistic are derived. The distribution theories and related properties of the test statistics are discussed. Percentage points and powers of the tests are tabulated for selected values of the parameters. The powers of these two tests are then compared to the two statistics proposed by Aly and Bouzar. The tests are applied to find epidemic changes in the set of Stanford heart transplant data and air traffic arrival data. [source]

Inflation Uncertainty and Monetary Policy in China

CHINA AND WORLD ECONOMY, Issue 3 2010
Chengsi Zhang
E31; E52; E58; E61 Abstract This paper uses a stochastic volatility model, structural break tests with unknown point, and a counterfactual simulation method to discuss the significant decline in inflation uncertainty in China over 1978,2009. We attempt to quantify the contributions of better monetary policy and smaller structural shocks (including demand, supply and policy impacts) on the reduced inflation uncertainty. Empirical results in the present paper suggest that improved monetary policy accounts for only a small fraction of the reduction in inflation uncertainty from the pre-1997 period to the post-1997 period in China. The bulk of the significant moderation in inflation uncertainty arises from smaller shocks. This finding indicates that the quiescence of inflation in China over the past decade could well be followed by a return to a more turbulent inflation era. Therefore, the use of preemptive monetary policy to anchor inflationary expectations and keep moderate inflation uncertainty is warranted. [source]

When did Louis Pasteur present his memoir on the discovery of molecular chirality to the Académie des sciences?

CHIRALITY, Issue 10 2008
Analysis of a discrepancy
Abstract Louis Pasteur presented his historic memoir on the discovery of molecular chirality to the Académie des sciences in Paris on May 22nd, 1848. The literature, however, nearly completely ignores this date, widely claiming instead May 15th, 1848, which first surfaced in 1922 in Pasteur's collected works edited by his grandson Louis Pasteur Vallery-Radot. On May 21st, 1848, i.e., one day before Pasteur's presentation in Paris, his mother died in Arbois, eastern France. Informed at an unknown point in time that she was "very ill," Pasteur left for Arbois only after his presentation. Biographies of Pasteur by his son-in-law René Vallery-Radot or the grandson, and Pasteur's collected correspondence edited by the grandson are incomprehensibly laconic or silent about the historic presentation. While no definite conclusions are possible, the evidence strongly suggests a deliberate alteration of the record by the biographer relatives, presumably for fear of adverse public judgment of Pasteur for a real or perceived insensitivity to a grave family medical emergency. Such fear would have been in accord with their hagiographic portrayal of Pasteur, and the findings raise questions concerning the extent of their zeal in protecting his "demigod" image. Universal recognition of the true date of Pasteur's announcement of molecular chirality is long overdue. Chirality, 2008. © 2008 Wiley-Liss, Inc. [source]