The Uniqueness of the Child–Father Attachment Relationship: Fathers' Sensitive and Challenging Play as a Pivotal Variable in a 16-year Longitudinal Study

This longitudinal study of forty‐four families explored fathers’ as compared to mothers’ specific contribution to their children's attachment representation at ages 6, 10, and 16 years. In toddlerhood, fathers’ and mothers’ play sensitivity was evaluated with a new assessment, the sensitive and challenging interactive play scale (SCIP). Fathers’ SCIP scores were predicted by fathers’ caregiving quality during the first year, were highly consistent across 4 years, and were closely linked to the fathers’ own internal working model of attachment. Qualities of attachment as assessed in the Strange Situation to both parents were antecedents for children's attachment security in the Separation Anxiety Test at age 6. Fathers’ play sensitivity and infant–mother quality of attachment predicted children's internal working model of attachment at age 10, but not vice versa. Dimensions of adolescents’ attachment representations were predicted by fathers’ play sensitivity only. The results confirmed our main assumption that fathers’ play sensitivity is a better predictor of the child's long‐term attachment representation than the early infant–father security of attachment. The ecological validity of measuring fathers’ sensitive and challenging interactive play behavior as compared to infant proximity seeking in times of distress is highlighted. Findings are discussed with respect to a wider view on attachment in that both parents shape their children's psychological security but each in his or her unique way.     

A Note on the Separability Principle in Economies with Single-Peaked Preferences

We consider the problem of allocating an infinitely divisible commodity among a group of agents with single-peaked preferences. A rule that has played a central role in the analysis of the problem is the so-called uniform rule. Chun (2001) proves that the uniform rule is the only rule satisfying Pareto optimality, no-envy, separability, and Ω-continuity. We obtain an alternative characterization by using a weak replication-invariance condition, called duplication-invariance, instead of Ω-continuity. Furthermore, we prove that the equal division lower bound and separability imply no-envy. Using this result, we strengthen one of Chun’s (2001) characterizations of the uniform rule by showing that the uniform rule is the only rule satisfying Pareto optimality, the equal division lower bound, separability, and either Ω-continuity or duplication-invariance.     

Applied general equilibrium modeling for long-term energy policy in Germany

The energy model is based on an extension of applied general equilibrium models of the Leontief input-output type, first implemented by Hudson and Jorgenson (1974). One objective of our project is to choose specifications of sectoral production and cost functions that permit us to estimate the unknown parameters of the price functions and input demand functions from a single input-output table in ten energy and 35 non-energy industries. Our second objective is to determine the price for capital and labor as well as the components of final demand endogenously instead of using a separate growth model as an engine for the economic development. Our third objective is to combine the concept of price-dependent substitution within the input structure with the concept of vintage coefficients for the latest plants. By this we incorporate into the input-output analysis the effect on growth as a result of investment, the effect on capacity as a result of new plants, and the effect on prices as a result of new technologies. An application of the model shows the long-term impact on growth and prices under alternative technologies in the electricity industry (nuclear or coal-fired power plants).     

Size, book-to-market, and momentum during the business cycle

The Fama–French-Methodology (1993–1998) offers cross-sectional explanations of returns by taking the specially designed portfolios SMB and HML as additional factors. It is acknowledged that these factors are related to some forms of risk (they bear premia) which, by researchers is often proposed to be related to the uncertainty with respect to macroeconomic production and aggregate consumption. In more recent research a momentum factor is included in order to improve the explanatory power of the Fama–French-Model. We use data from business cycles 1926–2007 to show that SMB represents the risks related to the very early phase of an upswing while HML may be related to the uncertainty whether a business cycle will continue to gain depth and strength (or shifts back into recession). In contrast to SMB and HML, we do not find momentum to be related to risks associated with particular phases of the business cycle.     

Subset Selection Toward Optimizing the Best Performance at a Second Stage

In the search for the best of n candidates, two-stage procedures of the following type are in common use. In a first stage, weak candidates are removed, and the subset of promising candidates is then further examined. At a second stage, the best of the candidates in the subset is selected. In this article, optimization is not aimed at the parameter with largest value but rather at the best performance of the selected candidates at Stage 2. Under a normal model, a new procedure based on posterior percentiles is derived using a Bayes approach, where nonsymmetric normal (proper and improper) priors are applied. Comparisons are made with two other procedures frequently used in selection decisions. The three procedures and their performances are illustrated with data from a recent recruitment process at a Midwestern university.