On Asymptotic Normality of the Local Polynomial Regression Estimator with Stochastic Bandwidths

Nonparametric density and regression estimators commonly depend on a bandwidth. The asymptotic properties of these estimators have been widely studied when bandwidths are non stochastic. In practice, however, in order to improve finite sample performance of these estimators, bandwidths are selected by data driven methods, such as cross-validation or plug-in procedures. As a result, nonparametric estimators are usually constructed using stochastic bandwidths. In this article, we establish the asymptotic equivalence in probability of local polynomial regression estimators under stochastic and nonstochastic bandwidths. Our result extends previous work by Boente and Fraiman (1995 Boente , G. , Fraiman , R. ( 1995 ). Asymptotic distribution of data-driven smoothers in density and regression estimation under dependence . Can. J. Statist. 23 : 383 – 397 .[Crossref], [Web of Science ®] , [Google Scholar]) and Ziegler (2004 Ziegler , K. ( 2004 ). Adaptive kernel estimation of the mode in nonparametric random design regression model . Probab. Mathemat. Statist. 24 : 213 – 235 . [Google Scholar]).     

Modeling Interval Time Series with Space–Time Processes

We consider interval-valued time series, that is, series resulting from collecting real intervals as an ordered sequence through time. Since the lower and upper bounds of the observed intervals at each time point are in fact values of the same variable, they are naturally related. We propose modeling interval time series with space–time autoregressive models and, based on the process appropriate for the interval bounds, we derive the model for the intervals’ center and radius. A simulation study and an application with data of daily wind speed at different meteorological stations in Ireland illustrate that the proposed approach is appropriate and useful.     

The effect of temporal aggregation on the estimation accuracy of ARMA models

ABSTRACT

Autoregressive Moving Average (ARMA) time series model fitting is a procedure often based on aggregate data, where parameter estimation plays a key role. Therefore, we analyze the effect of temporal aggregation on the accuracy of parameter estimation of mixed ARMA and MA models. We derive the expressions required to compute the parameter values of the aggregate models as functions of the basic model parameters in order to compare their estimation accuracy. To this end, a simulation experiment shows that aggregation causes a severe accuracy loss that increases with the order of aggregation, leading to poor accuracy.     

Competition for a Majority

We define the class of two‐player zero‐sum games with payoffs having mild discontinuities, which in applications typically stem from how ties are resolved. For such games, we establish sufficient conditions for existence of a value of the game, maximin and minimax strategies for the players, and a Nash equilibrium. If all discontinuities favor one player, then a value exists and that player has a maximin strategy. A property called payoff approachability implies existence of an equilibrium, and that the resulting value is invariant: games with the same payoffs at points of continuity have the same value and ɛ‐equilibria. For voting games in which two candidates propose policies and a candidate wins election if a weighted majority of voters prefer his proposed policy, we provide tie‐breaking rules and assumptions about voters' preferences sufficient to imply payoff approachability. These assumptions are satisfied by generic preferences if the dimension of the space of policies exceeds the number of voters; or with no dimensional restriction, if the electorate is sufficiently large. Each Colonel Blotto game is a special case in which each candidate allocates a resource among several constituencies and a candidate gets votes from those allocated more than his opponent offers; in this case, for simple‐majority rule we prove existence of an equilibrium with zero probability of ties.     

Eastern Donors and Western Soft Law: Towards a DAC Donor Peer Review of China and India?

The international system is still governed by a normative framework designed mainly by OECD countries, especially with regard to soft‐law standards in the field of development co‐operation. However, the growing relevance of ‘Eastern donors’ is weakening its efficiency and raises the question of how compliance with these standards can be assured in a changing donor landscape. Despite efforts to integrate emerging countries into the traditional approach of the OECD Development Assistance Committee (DAC) to monitoring compliance through peer reviews, the aid architecture of the future might turn out to be a synthesis of established and new approaches.     

Does export concentration matter in economic adjustment programs? Evidence from the euro-area

The recent crisis in some euro area countries is intensively fueling the political and economic policy debate about the effectiveness of the applied adjustment programs. This paper aims to contribute to explaining why the results of these programs could be different across countries, flagging the crucial role of exports. In view of recent economic literature about substitution between domestic and foreign sales, helping exports when domestic demand is adjusting, this paper uses panel data techniques to assess the role of the export structure in explaining this substitution effect in the euro area countries. Building a novel indicator for product concentration, the results suggest that domestic demand developments are more relevant to explaining exports in countries with a lower product concentration index (that is, more diversified exports). This contributes to explain why euro area countries under stress registered different economic performance, in particular the clearly less favorable behavior of Greece, where exports structure is concentrated more strongly in some goods and services than in other euro area countries. With different export behavior the final evaluation of the Greek adjustment would be certainly different. These results suggest that export structure should be taken into consideration when designing or evaluating this type of adjustment programs.     

Decision Making in Voluntary Career Change: An Other‐Than‐Rational Perspective

The authors present a qualitative study of voluntary career change, which highlighted the importance of positive emotions, unplanned action, and building certainty and perceiving continuity in the realization of change. Interpretative phenomenological analysis was used to broaden theoretical understanding of real‐life career decision making. The accounts of 8 women who had changed careers were explored, and the analysis supported other‐than‐rational perspectives of career decision making. An action‐affect‐cognition framework of decision making is proposed. The framework adds the role of emotion and the importance of self‐regulation to existing theory of career decision making. Implications for career counseling are discussed.     

Finite sample performance of frequency- and time-domain tests for seasonal fractional integration

Testing the order of integration of economic and financial time series has become a conventional procedure prior to any modelling exercise. In this paper, we investigate and compare the finite sample properties of the frequency-domain tests proposed by Robinson [Efficient tests of nonstationary hypotheses, J. Amer. Statist. Assoc. 89(428) (1994), pp. 1420–1437] and the time-domain procedure proposed by Hassler, Rodrigues, and Rubia [Testing for general fractional integration in the time domain, Econometric Theory 25 (2009), pp. 1793–1828] when applied to seasonal data. The results presented are of empirical relevance as they provide some guidance regarding the finite sample properties of these tests.