• Asia-Pacific Journal of Business
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• v.11 no.4
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• pp.37-48
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• 2020

Purpose - This study empirically investigates whether the risk property included in fat-tails of return distributions is systematic or unsystematic based on the devised statistical methods. Design/methodology/approach - This study devised empirical designs based on two traditional methods: principal component analysis (PCA) and the testing method of portfolio diversification effect. The fatness of the tails in return distributions is quantitatively measured by statistical probability. Findings - According to the results, the risk property in the fat-tails of return distributions has the economic meanings of eigenvalues having a value greater than 1 through PCA, and also systematic risk that cannot be removed through portfolio diversification. In other words, the fat-tails of return distributions have the properties of the common factors, which may explain the changes of stock returns. Meanwhile, the fatness of the tails in the portfolio return distributions shows the asymmetric relationship of common factors on the tails of return distributions. The negative tail in the portfolio return distribution has a much closer relation with the property of common factors, compared to the positive tail. Research implications or Originality - This empirical evidence may complement the existing studies related to tail risk which is utilized in pricing models as a common factor.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.10
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• pp.1389-1394
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• 2008

Abdominal fat characters are complex and economically important in the poultry industry. Their selection may benefit from the implementation of marker-assisted selection (MAS). The objective of this study was to identify the markers linked to QTL responsible for fatness traits. The Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) were used in the study. A total of 596 individuals from the divergent tails from the 6th to the 10th generations were genotyped at 23 microsatellite markers on chromosome 1. The differences of allele frequencies of all marker alleles between the divergent tails across the five generations were recorded. The allele frequencies of five markers, including LEI0209, LEI0146, MCW0036, ADL328 and MCW0115, had significant differences between the two tails in all five generations. The resulting p-values using Fisher's exact test on eleven markers, containing MCW248, MCW0010, MCW0106, LEI0252, LEI0068, MCW0018, MCW0061, LEI0088, MCW200, MCW283 and ROS0025, had a decreasing tendency from the 6th to the 10th generation. Statistical analysis showed that polymorphisms of the eight markers, including LEI0209, LEI0146, ROS0025, MCW0115, MCW0010, MCW0036, MCW283, ADL328, were significantly (p<0.0011) or suggestively (p<0.05) associated with abdominal fat content (AFW and AFP) across generations. It is concluded that the eight markers could be associated with the QTL affecting the deposition of abdominal fat in broiler chickens.

• Analyses & Alternatives
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• v.3 no.1
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• pp.135-157
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• 2019

The linkages between asset prices and macroeconomic outcomes are long-standing issue to both economists and monetary authorities. This paper explores the impact of asset prices on output and price in China. It focuses on the impacts of asset prices on the low quantiles of GDP gap and high quantiles of price gaprespectively. The main findings are the following: the influence of stock price gap, stock returns, and money growth on the different quantile of GDP gap and price gap are noticeable different, and there are significant impacts on the left tail of GDP gap distribution and on the right tail of price gap distribution. This implies that the results coming from simple regression will underestimate the economic risk imposed by asset price volatility. Moreover, these results also provide the caveat that one should cautiously distinguish the meaning of asset price gap and asset price growth rate and use them, through their contents are similar in some sense. One implication for monetarypolicy is that authority should interpret the relationship between asset prices and macro-economy in wider perspectives, and make the policy decision taking the impacts of asset prices on the tails of economy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.149-155
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• 1984

Raw and cooked pig's head, feet and tails were evaluated for yield, proximate composition, caloric value, and the contents of amino acids, minerals and vitamins. The yields of the raw pig's head, feet and tails were 67.4%, 46.1% and 67.6%, respectively. Corresponding values for the cooked were 54.1%, 34.3% and 47.6% respectively. No significant differences were observed for proximate composition between these samples and any other source3 of the meats. The high energy values, 253.8-310.5 Cal/100 g, of the samples were largely due to the fat content. Among the essential amino acids, these products showed a higher lysine, leucine and threonine content, and lower methionine and tryptophan content. The total amounts of non-essential amino acids were more than half of those of all amino acids. Neither the raw nor the cooked pig's head, feet and tails contained vitamin A. On these data, pig's head, feet and tails tissue have a relatively low in vitamin B content as compared to conventional pork cuts.

• Korean Journal of Veterinary Research
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• v.31 no.1
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• pp.1-10
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• 1991

The present investigation was focussed on histochemical and electron microscopical observations of utero-vaginal(U-V) glands in U-V junctions of domestic hens. In histochemical observations, fine granules by PAS technique for mucopolysaccharides and nile blue stain for acidic lipids were slightly stained on the cytoplasm of U-V glandular epithelium. Larger granules by Sudan black B stain for neutral fat and phospholipids and Sudan III stain for neutral fat were heavily stained on the perinuclear region of the U-V gland epithelial cells. These positive materials were heavily stained on the U-V glandular epithelium of lowfecundity hens and non-laying hens. In scanning electron microscopic findings of the U-V junction surface, the orifices of U-V glands are seen as the crater-like invagination. The neck of the U-V gland and the epithelium of U-V iunction were covered by ciliated epithelial cells. Aggregates of spermatozoa are observed often to be on the necks of the U-V gland. These spermatozoa heads are embedded in the glandular tubules and many spermatozoa tails are free on the epithelium of uterine surface. In transmission electron microscopic findings, the epithelial cells of the U-V glandular orifices were ciliated, columnar cells. The apical regions of these cells contained numerous electrondense, round secretory granules of uniformly size. The epithelial cells of the U-V glandular tubule were columnar or pyramid shape with round or oval nuclei. These epithelial cells have numerous microvilli and also contained electron-dense, round secretary granules of uniformly size and electron-lucent vesicles of various size. Spermatozoa are seen as the cross-sections of various regions of heads and tails in glandular tubules. Also spermatozoa arranged longitudinally parallel within the glandular tubules.

• The Korean Journal of Financial Management
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• v.24 no.3
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• pp.133-152
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• 2007

In this paper, we examine a portfolio selection model in which a safety-first investor maximizes expected return subject to a downside risk constraint. We use the Value-at-Risk as the downside risk measure. We exploit the fact that returns are fat-tailed, and use a semi-parametric method suggested by Jansen, Koedijk and de Vries(2000). We find a more realistic asset allocation than the one suggested by the literature based on the traditional mean-variance framework. For the robustness check, we provide empirical analyses using empirical quantiles. The results highlight that for optimal portfolio selection involving downside risks that are far in the tails of the distribution, our mean-VaR model with a fat-tailed distribution is superior.

• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2168-2177
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• 2018

The unavoidable forecast error of wind power is one of the biggest obstacles for wind farms to participate in day-ahead electricity market. To mitigate the deviation from forecast, installation of energy storage system (ESS) is considered. An accurate model of wind power forecast error is fundamental for ESS sizing. However, previous study shows that the error distribution has variable kurtosis and fat tails, and insufficient measurement data of wind farms would add to the difficulty of modeling. This paper presents a comprehensive way that makes the use of mixed skewness model (MSM) and copula theory to give a better approximation for the distribution of forecast error, and it remains valid even if the dataset is not so well documented. The model is then used to optimize the ESS power and capacity aiming to pay the minimal extra cost. Results show the effectiveness of the new model for finding the optimal size of ESS and increasing the economic benefit.

• The Korean Journal of Applied Statistics
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• v.29 no.1
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• pp.1-12
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• 2016

Contrasted with the standard linear ARMA models, financial time series exhibits non-standard features such as fat-tails, non-normality, volatility clustering and asymmetries which are usually referred to as "stylized facts" in financial time series context (Terasvirta, 2009). We are accordingly led to ad hoc models (apart from ARMA) to accommodate stylized facts (Andersen et al., 2009). The paper aims to give a contemporary overview on financial and special time series models based on the recent literature and on the author's publications. Various models are illustrated including asymmetric models, integer valued models, multivariate models and high frequency models. Selected statistical issues on the models are discussed, bringing some perspectives to the future works in this area.

• Journal of Life Science
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• v.18 no.7
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• pp.958-962
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• 2008

To get the nutritional data of hot water extract from imported kangaroo tails, research was done about contents of collagen, chondroitin sulfate, protein, fat, mineral ions, and conjugated linoleic acid (CLA) in tails. Collagen content of sulfuric acid digested sample was way higher at bones than meats in both kangaroo tail and cow tail. Comparing kangaroo tail and cow tail, meat of kangaroo tail have 1.7 times higher collagen content than that of cow tail. Content of collagen in bone parts of kangaroo tail was also higher 1.2 times than that of cow tail. Meat sample of kangaroo tail (liquid extraction) have 1.3 times higher content of muco-polysaccharide than that of cow tail. In the born part, kangaroo tail was 2.4 times higher than cow tail in its content of muco-polysaccharide. The CLA content of the kangaroo tail showed the content that was higher than 0.9% of the cow tail for 4.9% and showed about 5.3 times high ratios. Especially in kangaroo tail, a band with high content of CLA was found between C18:1 and C18:2.

• Journal of the Korean Applied Science and Technology
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• v.13 no.3
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• pp.15-24
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• 1996

Essentiality was proposed in the field of lipid by Burr and Burr in 1929. When rats were raised on the fat-free diet, their growth retarded and their skin and tails showed the characteristic deficient symptoms, which were relieved by the addition of ${\omega}6(n-6)$ polyunsaturated fatty acids as linoleic(LA) and arachidonic(AA) acids to the basal diet. LA is dehydrogenated to ${\gamma}-linolenic$ acid(GLNA) by ${\Delta}6$ desaturase, then GLNA is 2 carbon chain elongated by elongase to $dihomo-{\gamma}-linolenic$ acid(DGLNA), which is desaturated by ${\Delta}5$ desaturase to AA. These acids are called LA family or ${\omega}6(n-6)$ polyunsaturated fatty acids(PUFA). ${\alpha}-Linolenic$ acid(ALNA) is converted through the series of desaturation and elongation steps to docosahexaenic acid(DHA) via eicosapentaenoic acid(EPA). These acids belong to ALNA family or ${\omega}3(n-3)$PUFA. Human who consume large amounts of EPA and DHA, which are present in fatty fish and fish oils, have increased levels of these two fatty acids in their plasma and tissue lipids at the expense of LA and AA. Alternately, vegetarians, whose intake of LA in high, have more elevated levels of LA and AA and lower levels of EPA and DHA in plasma lipids and in cell membranes than omnivores. AA and EPA are metabolized to substances called eicosanoids. Those derived form AA are known as prostanocids(prostaglandins and prostacyclins) of the 2-types and leukotrienes of the 4-series, whereas those derived from EPA are known as prostanoids of the 3-types and leukotrienes of the 5-series. DGLNA is a precursor of the 1-types of prostaglandins. The metabolites of AA and EPA have competitive functions. Ingestion of EPA from fish or fish oil replaces AA from membrane phospholipids in practically all cells. So this leads to a more physiological state characterized by the production of proatanoids and leukotrienes that have antithrombic, antichemotactic, antivasoconstrictive and antiinflammatory properties. It is evident that ${\omega}3$ fatty acids can affect a number of chronic diseases through eicosanoids alone.