43,294 research outputs found
Robust Modeling Using Non-Elliptically Contoured Multivariate t Distributions
Models based on multivariate t distributions are widely applied to analyze
data with heavy tails. However, all the marginal distributions of the
multivariate t distributions are restricted to have the same degrees of
freedom, making these models unable to describe different marginal
heavy-tailedness. We generalize the traditional multivariate t distributions to
non-elliptically contoured multivariate t distributions, allowing for different
marginal degrees of freedom. We apply the non-elliptically contoured
multivariate t distributions to three widely-used models: the Heckman selection
model with different degrees of freedom for selection and outcome equations,
the multivariate Robit model with different degrees of freedom for marginal
responses, and the linear mixed-effects model with different degrees of freedom
for random effects and within-subject errors. Based on the Normal mixture
representation of our t distribution, we propose efficient Bayesian inferential
procedures for the model parameters based on data augmentation and parameter
expansion. We show via simulation studies and real examples that the
conclusions are sensitive to the existence of different marginal
heavy-tailedness
Leverage Financial News to Predict Stock Price Movements Using Word Embeddings and Deep Neural Networks
Financial news contains useful information on public companies and the
market. In this paper we apply the popular word embedding methods and deep
neural networks to leverage financial news to predict stock price movements in
the market. Experimental results have shown that our proposed methods are
simple but very effective, which can significantly improve the stock prediction
accuracy on a standard financial database over the baseline system using only
the historical price information.Comment: 5 pages, 2 figures, technical repor
FAMILY OWNERSHIP AND CONTROL IN LARGE FIRMS: THE GOOD, THE BAD, THE IRRELEVANT -- AND WHY
There is a major debate regarding the role of concentrated family ownership and control in large firms, with three positions suggesting that such concentration is (1) good, (2) bad, or (3) irrelevant for firm performance. This article reports two studies to shed further light on this debate. Study 1 uses 744 publicly listed large firms in eight Asian countries to test competing hypotheses on the impact of the combination of family ownership and control on firm performance. On a country-by-country basis, our findings support all three positions. On an aggregate, pooled sample basis, the results support the âirrelevantâ position. Study 2, based on a sample of 688 firms from the same eight Asian countries, endeavors to answer why Study 1 obtains different results for different countries. We theorize and document that Study 1 findings may be systematically associated with the level of shareholder protection embodied in legal and regulatory institutions. Study 2 thus sketches the contours of a cross-country, institution-based theory of corporate governance. Overall, our two studies lead to a finer-grained and more cumulative understanding of the crucial debate on family ownership and control in large firms.http://deepblue.lib.umich.edu/bitstream/2027.42/57220/1/wp840 .pd
FAMILY OWNERSHIP AND CONTROL IN LARGE FIRMS: THE GOOD, THE BAD, THE IRRELEVANT â AND WHY
There is a major debate regarding the role of concentrated family ownership and control in large firms, with three positions suggesting that such concentration is (1) good, (2) bad, or (3) irrelevant for firm performance. This article reports two studies to shed further light on this debate. Study 1 uses 744 publicly listed large firms in eight Asian countries to test competing hypotheses on the impact of the combination of family ownership and control on firm performance. On a country-by-country basis, our findings support all three positions. On an aggregate, pooled sample basis, the results support the âirrelevantâ position. Study 2, based on a sample of 688 firms from the same eight Asian countries, endeavors to answer why Study 1 obtains different results for different countries. We theorize and document that Study 1 findings may be systematically associated with the level of shareholder protection embodied in legal and regulatory institutions. Study 2 thus sketches the contours of a cross-country, institution-based theory of corporate governance. Overall, our two studies lead to a finer-grained and more cumulative understanding of the crucial debate on family ownership and control in large firms.corporate governance, family firm, ownership, Asia Pacific
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