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1.
The use of polygonal designs is motivated by the desire to avoid the selection of contiguous units in a sample from an ordered finite population. However very little is known about polygonal designs that have block size 5 or more. We present new polygonal designs with blocks of sizes 5 through 10, including the first designs with block sizes 9 and 10. For block sizes 5 through 7, we identify, with one possible exception, all values for the number of varieties for which a polygonal design exists. Received January 2001  相似文献   

2.
In this paper, the maximum determinant of the associated 0-1 matrix in D-Optimal saturated main effect plans for 3× s_2 × s_3 factorials, is derived by the use of Graph theory and Combinatorics. The present work is related to a problem suggested by Chatterjee and Narasimhan (2002). Using the theoretical results, we also give the designs for s3s2 + 1. This research was supported by the State Scholarships Foundation of Greece.  相似文献   

3.
We consider the uniformly most powerful unbiased (UMPU) one-sided test for the comparison of two proportions based on sample sizes m and n, i.e., the randomized version of Fisher's exact one-sided test. It will be shown that the power function of the one-sided UMPU-test based on sample sizes m and n can coincide with the power function of the UMPU-test based on sample sizes m+1 and n for certain levels on the entire parameter space. A characterization of all such cases with identical power functions is derived. Finally, this characterization is closely related to number theoretical problems concerning Fermat-like binomial equations. Some consequences for Fisher's original exact test will be discussed, too.  相似文献   

4.
Economics of Governance - This study investigates how state history influences the size of the informal sector. The study employs a two-stage least squares estimation technique with data from 91...  相似文献   

5.
The introduction of FRS (financial reporting standards) 136 to Malaysian PLC's (public limited company) in 2006 indirectly formalized accounting for purchased goodwill for the first time. Based on a sample of 2006 annual reports of 10 Main Board companies from plantation sector, the study finds the level of desired disclosure has yet to be met. Whilst the intention of the standard is noble, actual practice for first time reporting entities indicate that Malaysian PLC's and their auditors have far to go before they can meet the expectation set by FRS 136 in particular and International Financial Reporting Standards in general.  相似文献   

6.
Suppose the observations (X i,Y i), i=1,…, n, are ϕ-mixing. The strong uniform convergence and convergence rate for the estimator of the regression function was studied by serveral authors, e.g. G. Collomb (1984), L. Gy?rfi et al. (1989). But the optimal convergence rates are not reached unless the Y i are bounded or the E exp (a|Y i|) are bounded for some a>0. Compared with the i.i.d. case the convergence of the Nadaraya-Watson estimator under ϕ-mixing variables needs strong moment conditions. In this paper we study the strong uniform convergence and convergence rate for the improved kernel estimator of the regression function which has been suggested by Cheng P. (1983). Compared with Theorem A in Y. P. Mack and B. Silverman (1982) or Theorem 3.3.1 in L. Gy?rfi et al. (1989), we prove the convergence for this kind of estimators under weaker moment conditions. The optimal convergence rate for the improved kernel estimator is attained under almost the same conditions of Theorem 3.3.2 in L. Gy?rfi et al. (1989). Received: September 1999  相似文献   

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This paper empirically analyzes the effect of R&D activities, human resource and knowledge management, and the organization of knowledge sharing within a firm on the absorptive capacity of innovative firms for three different types of knowledge, namely absorptive capacity to use knowledge from a firm's own industry, knowledge from other industries and knowledge from research institutions. Using data from the German innovation survey, we investigate how firms are able to exploit knowledge from external partners for successful innovation activities. The estimation results show that the determinants of absorptive capacity differ with respect to the type of knowledge absorbed for innovation activities. In particular, we find that the R&D intensity does not significantly influence absorptive capacity for intra‐ and inter‐industry knowledge. Additionally, our results suggest that absorptive capacity is path dependent and firms can influence their ability to exploit external knowledge by encouraging individuals' involvement in a firm's innovation projects. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

9.
Ecological inference refers to the study of individuals using aggregate data and it is used in an impressive number of studies; it is well known, however, that the study of individuals using group data suffers from an ecological fallacy problem (Robinson in Am Sociol Rev 15:351–357, 1950). This paper evaluates the accuracy of two recent methods, the Rosen et al. (Stat Neerl 55:134–156, 2001) and the Greiner and Quinn (J R Stat Soc Ser A (Statistics in Society) 172:67–81, 2009) and the long-standing Goodman’s (Am Sociol Rev 18:663–664, 1953; Am J Sociol 64:610–625, 1959) method designed to estimate all cells of R × C tables simultaneously by employing exclusively aggregate data. To conduct these tests we leverage on extensive electoral data for which the true quantities of interest are known. In particular, we focus on examining the extent to which the confidence intervals provided by the three methods contain the true values. The paper also provides important guidelines regarding the appropriate contexts for employing these models.  相似文献   

10.
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