从语义学到心灵哲学： 重思对阿奎那关于理智之非物质性论证的一些批评

阿奎那关于个别感觉与普遍理性表征的理论是其对理智之非物质性论证的关键部分，但这一理论受到司各特、奥卡姆及布里丹等后来者的批评。然而，这些批评其实都不能成立。阿奎那的论证并不像罗伯特·帕斯纳奥对他的诘难中所说的那样，犯了从一个表征的语义内容推出此表征之本体论属性的“内容谬误”。此外，由布里丹本人的评论可以看出，布里丹实际上不得不接受他所批评的阿奎那论证所蕴含的主要内容。     

Search with small sets in presence of a liar

One unknown element of an n-element set is sought by asking if it is contained in given subsets. It is supposed that the question sets are of size at most k and all the questions are decided in advance, the choice of the next question cannot depend on previous answers. At most l of the answers can be incorrect. The minimum number of such questions is determined when the order of magnitude of k is n with <1. The problem can be formulated as determination of the maximum sized l-error-correcting code (of length n) in which the number of ones in a given position is at most k.     

EU-Funds Efficiency and the First National Development Plan in Hungary 2004–2006

The author highlights the importance of the difference between the efficiency and effectiveness of using the EU-subsidies. If Hungary cannot use the financial means of the EU efficiently and effectively, then the goal of cohesion and convergence to the level of the old, developed countries of the EU will be much more difficult and slower. The efficiency of the EU-subsidies involves a quantitative approach, where the ratio of the obliged and disposable amount of EU-subsidies can be measured. The effectiveness of EU-subsidies, on other hand, requires a much more complicated and complex approach, than the efficiency. The effectiveness of the usage on a project level can be measured by the “added value” of the project; on program level it can be measured by the added GDP growth or employment. The article presents the results of research carried out in the Research Group of Professor Tibor Palánkai at Corvinus University of Budapest, Hungary. S. G. Nagy is a member of the OTKA Research Group of Professor Tibor Palánkai (NI 68085).     

The Importance of Social Embeddedness: Churn Models at Mobile Providers

This article argues the importance of social embeddedness at mobile providers by examining the effects of customers’ network topological properties on churn probability—the probability of a customer switching from one telecommunication provider to another. This article uses data from regional snowball sampling—the only practically feasible network sampling method—to identify groups with significantly different churn ratios for customers with different network topological properties. Clear evidence indicates that individual network characteristics (node‐level metrics) have considerable impact on churn probabilities. The inclusion of network‐related measures in the churn model allows a longer‐term projection of churners and improves the predictive power of the model. With no possibility to carry out repeated sampling, sample stability was checked through simulation results. On the one hand, this article highlights the importance and effectiveness of the provider's tailored marketing campaigns by showing that customers targeted by direct marketing campaigns are less threatened by churn than nontargeted customers. On the other, this article shows that social embeddedness blocks the impact of the very same marketing efforts. This article forwards the idea that social embeddedness, also prevalent in vendor switching, can be extended to understanding the development of professional societies threatened by membership churn.     

Change Detection in INAR(p) Processes Against Various Alternative Hypotheses

Change in the coefficients or the mean of the innovation of an INAR(p) process is a sign of disturbance that is important to detect. The proposed methods can test for change in any one of these quantities separately, or in any collection of them. They make both one-sided and two-sided tests possible, furthermore, they can be used to test against the “epidemic” alternative. The tests are based on a CUSUM process using CLS estimators of the parameters. Under the one-sided and two-sided alternatives, consistency of the tests is proved and the properties of the change-point estimator are also explored.     

Testing stability in a spatial unilateral autoregressive model

ABSTRACT

Least squares estimator of the stability parameter ? ? |α| + |β| for a spatial unilateral autoregressive process X_{k, ?} = αX_{k ? 1, ?} + βX_{k, ? ? 1} + ?_{k, ?} is investigated and asymptotic normality with a scaling factor n^5/4 is shown in the unstable case ? = 1. The result is in contrast to the unit root case of the AR(p) model X_k = α₁X_{k ? 1} + ??? + α_pX_{k ? p} + ?_k, where the limiting distribution of the least squares estimator of the unit root parameter ? ? α₁ + ??? + α_p is not normal.