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51.
We show that in a discrete price and discrete time model for option pricing, specifically that given by the Cox–Ross–Rubinstein model, the arbitrage price of a European call option can depend on parameters other than volatility (the standard deviation of the log asset price). We provide two theorems to illustrate this phenomenon. Our first theorem considers two securities with the same volatility so that at a specified time n0, with probability near 1, the two securities are equal. If their call options differ, both the discounted securities will be martingales. Our second theorem considers two securities with the same volatility so that at times n = 0, ..., N ? 1 the securities are equal with probability near 1. If their call options differ, one of the discounted securities will be a martingale and the other discounted security will be a supermartingale.  相似文献   
52.
This observational post-marketing study of parenteral testosterone undecanoate (TU) in a non-selected population aimed to: examine the effectiveness of TU as treatment of hypogonadism; record adverse drug reactions (ADR) quantitatively particularly regarding polycythemia, prostate safety and cardiovascular-related metabolic risk factors; and verify whether recommended injection intervals apply to routine clinical practice. Eight hundred and seventy subjects from 259 outpatient units scheduled to visit the clinic six times were included. Effectiveness and tolerability of TU administration were assessed on a 4-point scale. Body weight, waist girth, blood pressure, hemoglobin levels, hematocrit, prostate-specific antigen (PSA), and digital rectal prostate examination were assessed. Over 90% of subjects completed the observational duration of 52.8?±?9.7 weeks (mean?±?SD) and 56% judged effectiveness as very good, 30.8% as good. 63.1% judged tolerability as very good, and 24.4% as good. No adverse effects on indicators of cardiovascular risk were observed. Polycythemia occurred in one subject and a supranormal hematocrit in one subject. Four subjects developed supranormal PSA levels. Prostate carcinoma was found in one subject, one subject had recurrence of a previously surgically treated prostate carcinoma, and the other two showed no indication of malignancy. Parenteral TU is safe, effective, and well-tolerated in clinical practice proving a good therapeutic option for hypogonadism.  相似文献   
53.
We concentrate on characteristics of minima XN from samples of iid lognormals X1i ~ 2pLND. We demonstrate that the distribution of XN for 2 ≤ N ≤ 1,000 may be fitted more accurately by 2pLND than by the limiting Gumbel distribution. An extended power model is established to represent the quotients CN/C1, where CN is the mean, standard deviation, or p-quantile of XN and C1 is the corresponding characteristic of X1i. Our empirical comparisons show that this model provides not only more accurate estimates than alternating approximations but it is also much simpler than its competitors.  相似文献   
54.
不同于其他动物,人类有时间意识和思考的能力。这就意味着,人类意识到自己对运气的依赖。宗教证实了这种依赖的感觉。今天,建立在超越人类的人格性存在基础上的宗教信仰已不再可能。不同于宗教的是,神秘主义通过放弃自身的愿望寻找精神的宁静。神秘主义,正如其印度和中国模式所展现的那样,是独立于宗教信仰的,其根本特点在于放弃人的自我中心主义。这一点将通过对道家的解释来阐明。  相似文献   
55.
Let G=(V,E) be a graph. A set SV is a restrained dominating set if every vertex in VS is adjacent to a vertex in S and to a vertex in VS. The restrained domination number of G, denoted γ r (G), is the smallest cardinality of a restrained dominating set of G. A graph G is said to be cubic if every vertex has degree three. In this paper, we study restrained domination in cubic graphs. We show that if G is a cubic graph of order n, then gr(G) 3 \fracn4\gamma_{r}(G)\geq \frac{n}{4} , and characterize the extremal graphs achieving this lower bound. Furthermore, we show that if G is a cubic graph of order n, then gr(G) £ \frac5n11.\gamma _{r}(G)\leq \frac{5n}{11}. Lastly, we show that if G is a claw-free cubic graph, then γ r (G)=γ(G).  相似文献   
56.
The article questions abstract concepts like lieux de mémoire, invented tradition and imagined communities linked to a concrete field of research. It reconstructs structures and practices of the cultural representation of mythical narrations in symbolic and social spaces. The case of a rural community in Austria after World War II shows that the encoding and decoding of a heroic saga is embedded both in the macro structures of the economic and political reconstruction of the Second Republic and the micro structures of the local festive culture. In the late 1940s, the supply of the narration, a variation of the German National myth of Herman the Cheruskian, met the demand of the majority of the villagers, above all the male inhabitants. In the 1950s, the market of cultural representations had changed: the hero of village memory became a relic of village history.  相似文献   
57.
On the Nature of Fair Behavior   总被引:17,自引:0,他引:17  
This article shows that identical offers in an ultimatum game generate systematically different rejection rates depending on the other offers that are available to the proposer. This result casts doubt on the consequentialist practice in economics to define the utility of an action solely in terms of the consequences of the action irrespective of the set of alternatives. It means in particular that negatively reciprocal behavior cannot be fully captured by equity models that are exclusively based on preferences over the distribution of material payoffs.  相似文献   
58.
Near-optimal designs for dual channel microarray studies   总被引:2,自引:0,他引:2  
Summary.  Much biological and medical research employs microarray studies to monitor gene expression levels across a wide range of organisms and under many experimental conditions. Dual channel microarrays are a common platform and allow two samples to be measured simultaneously. A frequently used design uses a common reference sample to make conditions across different arrays comparable. Our aim is to formulate microarray experiments in the experimental design context and to use simulated annealing to search for near-optimal designs. We identify a subclass of designs, the so-called interwoven loop designs, that seems to have good optimality properties compared with the near-optimal designs that are found by simulated annealing. Commonly used reference designs and dye swap designs are shown to be highly inefficient.  相似文献   
59.
碳酸盐检测是土壤科学中的常规检测。在本研究中,用中红外光谱方法对采自奥地利130多个不同的森林区域的大量土壤样品进行评价。评价了有机层中的20条谱带和矿物土壤中15条谱带区域,并且通过模型计算检测了被调查土壤样品中的碳酸盐。对于有机层的所有样品,相关系数都很低(R2=0.68),可以通过对F(中度分解的有机物)和H(高度腐烂的有机物质)的混合样品进行组分离来增加相关系数。FH层土壤、森林类型土壤、矿质土壤母质的相关系数达到R2=0.92。对于所有0到5和5至10cm的矿质土壤层,相关系数从一开始就很高(R2=0.97),当隔离一组石灰岩作为母质的10个样品时,相关系数可以增加到R2=0.99。最后,本研究着重介绍了土壤样品的化学多样性对于中红外光谱检测土壤中碳酸盐的影响潜力。  相似文献   
60.
The justice system has witnessed the negative consequences of chemical abuse. Infants are especially vulnerable to harm as a result of maternal drug use. This article uses a legal perspective to examine the conflict between maternal and fetal rights and reviews selected decisions and laws designed to protect children from maternal drug use. It advocates a policy of state intervention in order to protect children from the damage which can accompany maternal chemical use.  相似文献   
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