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通过引入一种新的估计方法——非参数假设检验方法,以达到对证券投资咨询机构对证券市场大盘走势预测准确度的估计.通过对估计结果的分析得出结论,有99%的把握认为,中国证券市场投资咨询机构所提供的对大盘涨跌的预测,每次有一半家数正确的概率没有达到45%,因而投资者应慎重对待投资咨询机构的大盘预测. 相似文献
44.
Martin Dowd 《Mathematical Logic Quarterly》1993,39(1):79-95
Adding higher types to set theory differs from adding inaccessible cardinals, in that higher type arguments apply to all sets rather than just ordinary ones. Levy's reflection axiom is justified, by considering the principle that we can pretend that the universe is a set, together with methods of Gaifman [8]. We reprove some results of Gaifman, and some facts about Levy's reflection axiom, including the fact that adding higher types yields no new theorems about sets. Some remarks on standard models are made. An obvious strengthening of Levy's axiom to higher types is considered, which implies the existence of indescribable cardinals. Other remarks about larger cardinals are made; some questions of Gloede [9] are settled. Finally we argue that the evidence for V = L is strong, and that CH is certainly true. MSC: 03E30, 03E55. 相似文献
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本文先介绍用不确定关系粗略计算一维线性谐振子零点能,然后再结合普朗克量子假设给出谐振子能级公式. 相似文献
47.
为了使航空公司获得更多的利润,应该尽量缩短乘客登机时间.以AirBus公司的A320飞机为例,利用已知统计数据、Matlab软件和R语言,建立登机顺序模型,并检验其合理性,同时设计出三种更好的模型供航空公司研究和实际操作. 相似文献
48.
Measurement theories are traditionally couched in algebraic terms, which makes them unsuitable for statistical testing. A probabilistic recasting of these theories is proposed here. It is observed then that an axiom of probabilistic measurement has typically the form of a logical polynomial, the structure of which induces a particular partition of the parameter space, giving rise to a calss of statistical problems for which the null hypothesis is a union of convex polyhedrons. This is a consequence of the fact that a logical polynomial can always be rewritten in normal form, that is, as a disjunction of conjunctions. A likelihood ratio method is worked out in a couple of exemplary cases. One of these examples provides a test of transitivity, a property which lies at the heart of ordinal measurement. 相似文献
49.
Let {Xt} be a Gaussian ARMA process with spectral density fθ(λ), where θ is an unknown parameter. The problem considered is that of testing a simple hypothesis H:θ = θ0 against the alternative A:θ ≠ θ0. For this problem we propose a class of tests
, which contains the likelihood ratio (LR), Wald (W), modified Wald (MW) and Rao (R) tests as special cases. Then we derive the χ2 type asymptotic expansion of the distribution of T
up to order n−1, where n is the sample size. Also we derive the χ2 type asymptotic expansion of the distribution of T under the sequence of alternatives An: θ = θ0 + /√n, ε > 0. Then we compare the local powers of the LR, W, MW, and R tests on the basis of their asymptotic expansions. 相似文献
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Martin Goldstern Saharon Shelah 《Transactions of the American Mathematical Society》2005,357(9):3525-3551
We show that (consistently) there is a clone on a countable set such that the interval of clones above is linearly ordered and has no coatoms.