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Apart from biographies and memoirs of outstanding leaders, studies on the development of leaders in everyday life from childhood to maturity are rare. We propose a developmental model of leaders in which certain variables formed in early childhood are the basic components for leadership development in later life. These are a low level of trait anxiety [Spielberger, C.D. (1972). Conceptual and methodological issues in anxiety research. In C.D. Spielberger (Ed.), Anxiety: Current trends in theory and research. New York: Academic Press, vol. 1] and openness to experiences [Costa, P.T. Jr., & McCrae, R.R. (1992a). Revised NEO Personality Inventory (NEO-PI-R) and NEO Five-Factor Inventory (NEO-FFI) professional manual. Odessa, FL: Psychological Assessment Resources]. We argue that secure attachment style [Bowlby, J. (1969). Attachment and loss: Vol. 1. Attachment. New York: Basic Books] explains the formation and influence of these basic components, which in turn affect the leader's development through experience in leadership roles. Questionnaires were administered to 286 subjects. The data obtained were analyzed by structural equation modeling (SEM).The findings show that trait anxiety and openness to experience affect leaders' development via experiences. Alternative models in which formative variables may affect the magnitude and intensity of leadership experiences are discussed.  相似文献   
13.
A graph is locally irregular if the neighbors of every vertex v have degrees distinct from the degree of v. A locally irregular edge-coloring of a graph G is an (improper) edge-coloring such that the graph induced on the edges of any color class is locally irregular. It is conjectured that three colors suffice for a locally irregular edge-coloring. In the paper, we develop a method using which we prove four colors are enough for a locally irregular edge-coloring of any subcubic graph admiting such a coloring. We believe that our method can be further extended to prove the tight bound of three colors for such graphs. Furthermore, using a combination of existing results, we present an improvement of the bounds for bipartite graphs and general graphs, setting the best upper bounds to 7 and 220, respectively.  相似文献   
14.
Under a simple superpopulation model for an arbitrary sampling design we derive optimal linear unbiased estimators/predictors of a mean in a domain. They can be viewed as synthetic and composite estimators of small area estimation theory when no auxiliary variable is available. Moreover, we show that the only requirement for optimality of a sampling strategy is to use any sampling plan of fixed sample size together with traditional estimators (as designed for simple random sampling without replacement). Finally, for symmetric sampling plans, simplified formulas (based on the first two moments of sample sizes) for optimal synthetic and composite estimators and their MSE’s are derived. Throughout the paper we consistently use the model-design setup.  相似文献   
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Abstract

One of the basic statistical methods of dimensionality reduction is analysis of discriminant coordinates given by Fisher (1936 Fisher, R. A. 1936. The use of multiple measurements in taxonomic problem. Annals of Eugenics 7 (2):17988. doi:10.1111/j.1469-1809.1936.tb02137.x.[Crossref] [Google Scholar]) and Rao (1948). The space of discriminant coordinates is a space convenient for presenting multidimensional data originating from multiple groups and for the use of various classification methods (methods of discriminant analysis). In the present paper, we adapt the classical discriminant coordinates analysis to multivariate functional data. The theory has been applied to analysis of textural properties of apples of six varieties, measured over a period of 180?days, stored in two types of refrigeration chamber.  相似文献   
16.
The paper is about portfolio selection in a non-Markowitz way, involving uncertainty modeling in terms of a series of meaningful quantiles of probabilistic distributions. Considering the quantiles as evaluation criteria of the portfolios leads to a multiobjective optimization problem which needs to be solved using a Multiple Criteria Decision Aiding (MCDA) method. The primary method we propose for solving this problem is an Interactive Multiobjective Optimization (IMO) method based on so-called Dominance-based Rough Set Approach (DRSA). IMO-DRSA is composed of two phases: computation phase, and dialogue phase. In the computation phase, a sample of feasible portfolio solutions is calculated and presented to the Decision Maker (DM). In the dialogue phase, the DM indicates portfolio solutions which are relatively attractive in a given sample; this binary classification of sample portfolios into ‘good’ and ‘others’ is an input preference information to be analyzed using DRSA; DRSA is producing decision rules relating conditions on particular quantiles with the qualification of supporting portfolios as ‘good’; a rule that best fits the current DM’s preferences is chosen to constrain the previous multiobjective optimization in order to compute a new sample in the next computation phase; in this way, the computation phase yields a new sample including better portfolios, and the procedure loops a necessary number of times to end with the most preferred portfolio. We compare IMO-DRSA with two representative MCDA methods based on traditional preference models: value function (UTA method) and outranking relation (ELECTRE IS method). The comparison, which is of methodological nature, is illustrated by a didactic example.  相似文献   
17.
The sampling designs dependent on sample moments of auxiliary variables are well known. Lahiri (Bull Int Stat Inst 33:133–140, 1951) considered a sampling design proportionate to a sample mean of an auxiliary variable. Sing and Srivastava (Biometrika 67(1):205–209, 1980) proposed the sampling design proportionate to a sample variance while Wywiał (J Indian Stat Assoc 37:73–87, 1999) a sampling design proportionate to a sample generalized variance of auxiliary variables. Some other sampling designs dependent on moments of an auxiliary variable were considered e.g. in Wywiał (Some contributions to multivariate methods in, survey sampling. Katowice University of Economics, Katowice, 2003a); Stat Transit 4(5):779–798, 2000) where accuracy of some sampling strategies were compared, too.These sampling designs cannot be useful in the case when there are some censored observations of the auxiliary variable. Moreover, they can be much too sensitive to outliers observations. In these cases the sampling design proportionate to the order statistic of an auxiliary variable can be more useful. That is why such an unequal probability sampling design is proposed here. Its particular cases as well as its conditional version are considered, too. The sampling scheme implementing this sampling design is proposed. The inclusion probabilities of the first and second orders were evaluated. The well known Horvitz–Thompson estimator is taken into account. A ratio estimator dependent on an order statistic is constructed. It is similar to the well known ratio estimator based on the population and sample means. Moreover, it is an unbiased estimator of the population mean when the sample is drawn according to the proposed sampling design dependent on the appropriate order statistic.  相似文献   
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This article examines the parallels between George H. Mead's theory of time and Boris A. Uspensky's semiotics of history, looking for implications relevant to the symbolic interactionist theory of historical processes. It suggests that Mead's theory of time and theory of communication hold important implications for semiotic analysis of the historical dimension of sociocultural phenomena. A further aim is to link the symbolic interactionist tradition of the Chicago school with the Tartu school and its semiotics of history. This would fuel the further development of both theoretical orientations.  相似文献   
20.
A review of the literature on Radio Free Europe’s role throughout the Cold War reveals its underdeveloped historiography. Yet, how valuable are RFE’s reports and broadcasts as a tool for historical exploration? Drawing on a wealth of materials from Polish programming, this analysis uses the case study of the role of the Catholic Church in Poland throughout the 1950s and the 1960s, to appraise not only the content of RFE reports but also the extent to which they can be used as a historical tool. The reports reveal, for example, that the Church became politically active already in the mid 1960s during its struggle with the Communist regime over the Millennium anniversary celebrations and the issue of Poland’s Western territories. This analytical framework allows for an examination of RFE’s comments in terms of what they might tell us about what really happened, and in terms of what they actually tell us about the station’s perceptions of what happened. The station’s position as an observer, critic and participant in the turmoil of the Cold War, gave it a distinct ability to access both the realities behind the Iron Curtain and the Western perceptions of what was happening in the satellite countries.  相似文献   
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