电感耦合等离子体发射光谱法测定再制蛋中钠含量的不确定度

采用电感耦合等离子体发射光谱法测定再制蛋中钠含量及其测量不确定度,建立数学模型;通过对不确定度分量的合成、扩展及评定,找出影响不确定度的最主要因素来源于标准曲线的拟合,再制蛋中钠含量可表示为1.02×103±26.2 mg/100 g(k=2)。     

连续监测法检测血清中ALT结果的测量不确定度评定

通过对连续监测法检测血清中ALT测量过程的分析,确定并简化测量不确定度的来源;采用不确定度A类评定和不确定度B类评定方法,量化各不确定度分量;计算合成不确定度与扩展不确定度。当ALT=66.5 U/L时,连续监测法检测血清中ALT的扩展不确定度为U=3.81U/L（K=2,置信水平95%）;在各不确定度分量中,由标准品所引入的测量不确定度分量所占比重最大。依据JJF1059-1999《测量不确定度评定与表示》可对连续监测法检测血清中ALT的测量不确定度进行合理评定。     

高效液相色谱法测定肉制品中双乙酸钠的不确定度评定

按照GB/T 23383-2009利用反相高效液相色谱法对肉制品中双乙酸钠含量进行分析,建立数学模型,对测量结果的不确定度来源如标准物质、校准工作曲线、样品处理、回收率等各不确定度分量进行分析评定及量化。按数学模型计算得肉制品中双乙酸钠含量为0.460g/kg时,本方法的标准不确定度为0.022g/kg,扩展不确定度为0.044g/kg,最终结果的不确定度主要由样品溶液中双乙酸钠含量和样品处理过程产生。     

火焰原子吸收光谱法测定奶粉中镁含量的不确定度评定

建立微波消解-火焰原子吸收光谱法测量奶粉中镁含量的不确定度评定方案,合理地赋予被测量值的分散性。本文以火焰原子吸收光谱法测定婴幼儿配方乳粉中镁含量为例,全面分析并评估各不确定度分量,合成并计算得到扩展不确定度。本实验结果为(489.7±18.7)mg/kg,分析表明标准曲线配制及设备校准过程产生不确定度最大,测试中需重点关注标准曲线配制及测量设备优化过程。本方案适用于火焰原子吸收光谱法测定食品中镁、钙等金属离子含量的不确定度评定。     

离子色谱法检测饲料级氯化胆碱含量的测量不确定度评定

本文对影响离子色谱法检测饲料级氯化胆碱含量的不确定度产生来源进行了分析,建立相应的数学模型,并对数学模型中各个不确定度分量进行了评定。利用测量不确定度理论,计算不确定度分量和合成不确定度,得到离子色谱法检测饲料级氯化胆碱含量的扩展不确定度为0.816%。     

分光光度法测定水中铁不确定度评定

[目的]全面评定分光光度法不正确定度来源.[方法]采用分光光度法测定水中微量铁,并对测量结果进行不确定度的评定和说明.[结果]测量结果:0.606mg/L;测量扩展不确定度:0.036mg/L(K=2).[结论]标准曲线拟合引入的不确定度分量是不确定度分量中最大的,因此降低该分量对降低该方法测量不确定度效果最明显.     

固相酶联免疫法测定花生油中黄曲霉毒素B_1的不确定度评定

本文分析利用固相酶联免疫吸附(ELISA)原理测定花生油中黄曲霉毒素B_1所引入的不确定度,根据JJF 1059.1-2012《测量不确定度评定与表示》的规定,评定实验中所涉及的重复测量、样品的称量和稀释、工作曲线、加标回收等引入的不确定度分量。     

HPLC法测定面包中脱氢乙酸的不确定度评定

评定高效液相色谱法测定面包中脱氢乙酸含量的不确定度。依据国家计量技术规范JJF 1059.1-2012《测量不确定度评定与表示》,建立脱氢乙酸不确定度的数学模型,并对各不确定度分量进行分析,计算合成不确定度和扩展不确定度。结果表明,当样品中脱氢乙酸的含量为0.2547 g·kg~(-1)时,其扩展不确定度为0.0065 g·kg~(-1)(P=95%,k=2),标准曲线配制、标准曲线拟合、加标回收、重复性测量是测量不确定度的主要来源。     

出口蔬菜中氯氰菊酯残留量测量的不确定度评定

采用GB/T 19648-2006《水果和蔬菜中500种农药及相关化学品残留量的测定气相色谱-质谱法》进行样品前处理,利用GC-ECD法测定出口蔬菜中氯氰菊酯残留量的相应数学模型,对数学模型中各不确定因素进行了量化处理。对各不确定度分量合成和扩展,得到出口蔬菜中氯氰菊酯残留量的扩展不确定度为0.0178mg/kg。结果表明：标准溶液及曲线的建立、定容和进样体积及测量随机性因素是主要不确定度来源。     

LC-MS检测化妆品中糖皮质激素的不确定度研究

根据JJF1059-1999《测量不确定度评价与表示》对建立液相色谱-质谱测定方法的不确定度评定方式,对糖皮质激素的测定进行不确定度分析。通过对地塞米松测定过程建立数学模型,包括对称重、溶液配制等方面,其中在方法的不确定度评定过程中,应主要考虑不确定度贡献较大的分量,从而简化实验操作步骤,提高工作效率。通过对标准曲线、称量、标准溶液配制、实验人员、环境等因素引入的不确定度进行分析,置信区间为95%时,k=2,得出不确定度结果为UC=31.40mg/mL,地塞米松含量c=（397.45±32.66）mg/mL。     

钼蓝光度法测定钼铁中磷量的不确定度评定

按照国家标准GB/T5059.6-2007中的方法Ⅱ进行钼铁中磷含量的测定,对测定过程中产生不确定度的原因进行分析,并对测量结果的不确定度进行评定。该方法测定磷量的扩展不确定度U=0.002%,置信区间为95%。     

Opening Local Retail Food Stores: A Real-Options Approach

A real-options approach was used, incorporating uncertainty and irreversibility of investments, to study the number of stores entering the Swedish retail food market during the period 1994–2002. It was found that uncertainty affected the entry-decision. Entry was less frequent in highly concentrated local retail food-markets characterized by a high degree of uncertainty, whereas higher profit opportunities seem to have increased the probability of entry.     

环境不确定性、内部控制质量与持续经营审计意见--来自财务困境上市公司的经验证据

以2009－2012年我国A股财务困境上市公司为研究样本，检验环境不确定性及内部控制质量对审计师持续经营审计意见决策的影响。研究发现，公司环境不确定性越高则更可能被出具持续经营审计意见，高质量内部控制将有助于缓解其持续经营疑虑，但上述关系仅在非国有上市公司中存在；进一步的检验还发现，在高环境不确定性的背景下，高质量内部控制缓解持续经营疑虑主要源于良好的风险评估机制。上述研究发现一方面证实了高质量的内部控制有助于缓解处于较高不确定性环境中财务困境公司的持续经营问题，另一方面也揭示了政府的隐性担保和天然政治联系使得国有财务困境公司不需要凭借高质量内部控制也能够缓解持续经营危机。     

SHACKLE AND MODERN DECISION THEORY

The paper discusses the role of George L.S. Shackle in fostering an unconventional approach to individual decision making. Up until the early 1970s Shackle was the single critic of the probabilistic approach to decision making who proposed an alternative formal corpus for dealing with uncertainty. The main aim of the paper is to analyse Shackle's non‐probabilistic conceptualization of individual decisions under uncertainty from a specific viewpoint, namely that of a possible connection between his theory and one of the most interesting recent approaches to decision under uncertainty, the so‐called non‐additive probability approach of Gilboa and Schmeidler. The paper shows that these developments in modern decision theory take Shackle's issue seriously and confirm that the reliance of strict Bayesian theory on probabilistic judgements based on point‐probability estimates, a reliance that Shackle intended to oppose, is untenable. Non‐additive decision theory also provides a usage of non‐additive probability distributions in choice that is an alternative to Shackle's approach of using a qualitative notion of probability, such as potential surprise.     

The path-to-profitability of Internet IPO firms

Extant empirical evidence indicates that the proportion of firms going public prior to achieving profitability has been increasing over time. This phenomenon is largely driven by an increase in the proportion of technology firms going public. Since there is considerable uncertainty regarding the long-term economic viability of these firms at the time of going public, identifying factors that influence their ability to attain key post-IPO milestones such as achieving profitability represents an important area of research. We employ a theoretical framework built around agency and signaling considerations to identify factors that influence the probability and timing of post-IPO profitability of Internet IPO firms. We estimate Cox Proportional Hazards models to test whether factors identified by our theoretical framework significantly impact the probability of post-IPO profitability as a function of time. We find that the probability of post-IPO profitability increases with pre-IPO investor demand and change in ownership at the IPO of the top officers and directors. On the other hand, the probability of post-IPO profitability decreases with the venture capital participation, proportion of outsiders on the board, and pre-market valuation uncertainty.     

奈特不确定下资产定价消费模型的建立

在不确定条件下进行资产定价是金融学中的一个重要问题。受金融市场的时变性和人的参与,通常情况下很难得到如收益、利率、波动率等某些变量的精确估计值,现实金融市场中不仅存在概率意义上的不确定性,还存在模糊性,在实际投资中如何对不确定性给出正确的建模就变得非常重要。把不确定性理论引入到传统的资产定价模型中,通过引入不确定性惩罚因子和熵函数建立奈特不确定条件下的最优消费和投资组合模型,能够同时反映随机不确定性和模糊性,可满足投资者的需求。该模型是对经典模型的一种自然推广,它可以适用于不同类型的市场,不同类型的个体,有较好的适用性。     

石墨炉原子吸收分光光度法测定水样中铬的不确定度

[目的]通过对影响测定结果的不确定度因素的分析和量化,评价石墨炉原子吸收光谱法测定水样中铬的不确定度。[方法]调节仪器最佳测定条件,测定铬标准工作溶液系列并依据工作软件自动建立工作曲线和数学模型;连续测量10次水样,根据标准曲线获得未知样品铬浓度;分析石墨炉原子吸收分光光度法测定水样中铬的误差性质和来源,确定不确定度的主要因素,计算水样中铬的测量不确定度。[结果]扩展不确定度U95=0.016mg/L（Veff=20）。[结论]根据分析仪器的测定数据输出方式建立数学模型,进行不确定度评定,方法直观简明,与实际工作相符合。     

Setting price or quantity: Depends on what the seller is more uncertain about

We consider a seller with uncertain demand for its product. If the demand curve were certain, then setting price and setting quantity would be equivalent ways to frame the seller’s problem of choosing a profit-maximizing point on its demand curve. With uncertain demand, these become distinct sales mechanisms. We distinguish between uncertainty about the market size and uncertainty about the consumers’ valuations. Our main results are that (i) for a given marginal cost, an increase in uncertainty about valuations favors setting quantity whereas an increase in uncertainty about market size favors setting price; (ii) keeping demand uncertainty fixed, there is a nonmonotonic relationship between marginal costs and the optimal selling mechanism (setting price or quantity); and (iii) in a bilateral monopoly channel setting, coordination occurs except for a conflict zone in which the retailer’s choice of a selling mechanism deviates from the coordinated channel selling mechanism.     

The Primitive Uncertainty Construct: Possibility,Potential Surprise,Probability and Belief; Some Experimental Evidence

This paper investigates the nature of the primitive uncertainty measure by means of a laboratory experiment that consists of four uncertain situations. It considers the related pair of possibility and potential surprise associated with George Shackle; and the supposedly related pair, belief and probability. The assessment of the relative merits of potential measures of uncertainty is based upon modal responses and χ² tests. It is found that the dominant uncertainty concept is potential surprise, and the subjects' explanations of their choice of an uncertainty concept gave substantial weight to possibility where it is felt that there is vagueness or doubt about the outcomes in a given situation     

Price uncertainty and competitive firm behavior: Testable hypotheses from expected utility maximization

This article derives the general implications of expected utility maximization for the static model of the competitive firm under output price uncertainty for any risk preference and probability structure. Implications of the results for the empirical analysis of risk-responsive behavior under uncertainty are discussed.