bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time Inconsistency and the Exchange Rate Channel of Monetary Policy
Authors: Leitemo Kai , Roisland Øistein , Torvik Ragnar 
Published: March 2003

This paper analyses time–inconsistency problems related to the exchange rate channel of monetary policy. Within a simple open–economy macroeconomic model, where the exchange rate is the only forward–looking variable, we show that a difference emerges between optimal policy under discretion and under commitment. Moreover, the nature of the time–inconsistency problem resembles that resulting from standard New Keynesian models: when cost–push shocks occur, the exchange rate channel gives rise to excessive output stabilisation and insufficient inertia in monetary policy under a discretionary policy. JEL classification: E42; E52; E61
The role of spatial configuration in tests of working memory explored with functional neuroimaging
Authors: Bor Daniel , Duncan John , Owen Adrian 
Published: March 2003

While the importance of the prefrontal cortex for “higher‐order” cognitive functions is largely undisputed, no consensus has been reached regarding the fractionation of functions within this region. Several recent functional neuroimaging studies have suggested that the mid‐ventrolateral frontal cortex may play an important role in various aspects of human memory. Thus, similar patterns of activation have been observed in this region during analogous spatial, verbal and visual span tasks. In the present study, however, activation was observed in a more dorsolateral region of the lateral frontal cortex during a modified version of the spatial span task, which differed only in the spatial configuration of the array employed. The results of a supplementary behavioral study, designed to investigate this effect further, suggest that in spatial memory tasks certain stimulus configurations may encourage subjects to adopt mnemonic strategies, which may depend upon dorsolateral, rather than ventrolateral, regions of the frontal cortex.These findings shed further light on the functional relationship between dorsal and ventral regions of the lateral frontal cortex and, more specifically, how the “executive” processes assumed to be dependent upon these regions might contribute to aspects of human memory.
High Tech or High Touch: Will Technology Help or Hurt Our Teaching?
Authors: Mercadante Linda 
Published: March 2003

Books reviewed in this article:David G. Brown, Interactive Learning: Vignettes from America's Most Wired CampusesMarc Eisenstadt and Tom Vincent, The Knowledge Web: Learning and Collaborating on the NetPat Maier, Liz Bamett, Adam Warren, and David Brunner, Using Technology in Teaching and LearningAdam Warren, David Brunner, Pat Maier, and Liz Barnett, Using Technology in Teaching and Learning: An Introductory GuideSteve Ryan, Bernard Scott, Howard Freeman, and Daxa Patel, The Virtual University: The Internet and Resource‐Based Learning
The Foreign Exchange Origins of Japan's Economic Slump and Low Interest Liquidity Trap
Authors: McKinnon Ronald , Ohno Kenichi 
Published: March 2003

Japan's macroeconomic problem has yet to be properly diagnosed. Throughout the 1990s, policy makers could not decide on the proper macro economic measures to combat the country's severe economic slump. We propose a unified explanation, with deep historical roots, of why aggregate private demand failed to recover after Japan's stock and real estate bubbles burst in 1991 and deflationary pressure continues.The problem is not purely ‘made in Japan’. It arises from Japan's unbalanced mercantile relationship with the United States. Starting in the early 1970s, numerous trade disputes between the two countries created tensions that were (temporarily) resolved by the yen going ever higher against the dollar up to 1995. In the last two decades, this persistent pressure for the yen to rise was further aggravated by Japan's large current‐account (saving) surpluses as the counterpart of America's large current account (saving) deficits. The legacy is the expectation that trade and financial tensions will recur so that the yen will be higher 10, 20, or 30 years from now –with Japan's (wholesale) price level forced correspondingly lower and nominal interest rates on yen assets remaining more than four percentage points less than those on dollar assets.This fear of yen appreciation, whose timing is erratic and unpredictable, now inhibits private domestic investment by both Japanese firms and households. Our theory also explains why, in the late 1990s, nominal interest rates on short‐term yen assets were compressed toward zero so as to destroy the normal profit margins of the banking system. In this liquidity trap, the Bank of Japan –whose monetary policy has been quite ‘expansionary’–is powerless to stimulate the flagging economy.To spring the liquidity trap, eliminate deflationary pressure, and restore macro economic balance in Japan, the American and Japanese governments must act jointly to quash the expectation that the yen will be higher in the future than it is today.
A Dutch comprehension test for identifying reading problems in L1 and L2 students (Research Note)
Authors: Hacquebord Hilde 
Published: March 2003

The Dutch Text Comprehension Test was developed in order to help improve the education of minority students in the Netherlands. As it appeared that many second language (L2) readers have more difficulties with respect to the micro‐processing of words and sentences while compensating on the macro level, there was a need for an instrument with diagnostic value so as to yield clues for further remedial teaching. The test proved reliable for both L1 students and L2 students. The test, with regard to diagnosing the type of reading problem, was validated by carrying out further observations by video. Although the classification results were not optimal, the test can be used for diagnostic purposes provided that there is a relatively large difference between sub‐test scores on the micro and the macro levels.The results of a screening survey show that there are great differences in percentages of weak readers and distribution of reader types among the different secondary school types in the Netherlands. Unlike weak readers who attend the higher school types, weak readers at the lower educational school types – among them many L2 readers – are ‘problem readers’ who do not compensate for their lack of word knowledge and sentence processing and who do not appear to be efficient ‘bottom‐up readers.’ Secondary schools are therefore encouraged to screen their first year students in order to gain insight into the problems that weaker readers – including L2 readers – may have, and to develop remedial teaching programmes tailored to the different needs of L1 and L2 students.
Computer‐based cognitive assessment and the development of reading
Authors: Singleton Chris , Thomas Kevin , Horne Joanna 
Published: March 2003

This paper reports on a longitudinal study using the computer‐based cognitive assessment system CoPS, and considers the applicability of this system in the early identification of cognitive strengths and limitations that affect the development of reading. CoPS comprises eight tests of basic cognitive abilities, including phonological awareness, auditory discrimination, and short‐term visual and auditory‐verbal memory. A total of 421 children participated in the study. Assessment with the CoPS tests was carried out at age 5 years, and follow‐up assessments using conventional tests of reading and general ability were carried out at 6 and 8 years of age.Correlations between the CoPS tests administered at age 5 and reading ability at age 8 were in the region of 0.6 for auditory‐verbal memory and phonological awareness, and in the region of 0.3 for the CoPS measure of auditory discrimination as well as most of the other memory measures. Stepwise linear regression analyses showed that the CoPS tests of auditory‐verbal memory and phonological awareness administered at age 5 together accounted for 50% of the variance in reading ability at age 8, compared with only 29% of the variance being attributable to intelligence. It was concluded that short‐term memory is an important predictor variable for reading, in addition to the more generally acknowledged variable of phonological processing.Discriminant function analysis showed that CoPS tests provide a highly satisfactory prediction of poor reading skills, with very low or zero rates for false positives and false negatives. By contrast, a word recognition test given at age 6 was not found to predict reading at age 8 to the same degree of accuracy, resulting in an unsatisfactory false positive rate of 21%. Measures of verbal and nonverbal ability at age 6 produced unacceptably high false positive rates between 50% and 70%. These findings are discussed in relation to the prediction of children at risk of reading failure. The potential of computer‐based cognitive profiling for facilitating differentiated teaching in early reading is also considered.
A Comparison of Statistical Methods for Age-related Reference Intervals
Authors: Wright Eileen M. , Royston Patrick 
Published: March 2003

Summary
Age-specific reference intervals are commonly used in the routine monitoring of individuals, where interest lies in the detection of extreme values, possibly indicating abnormality. Here, a review is given of the wide range of statistical techniques which have been proposed for the construction of these intervals and issues such as the estimation of confidence bands and goodness of fit are discussed. Three methods, thought to be the most widely applied approaches, are considered in more detail. Comparisons are made on the basis of reference interval estimation for three real data sets.
The Statistics of the National Lottery
Authors: Haigh John 
Published: March 2003

Summary
Some methods to test the randomness of the numbers drawn in the UK National Lottery are described. The data for the first 96 draws are consistent with the numbers being drawn at random, both in terms of the individual frequencies and of the waiting times for successive appearances. The number combinations chosen by gamblers are shown to be far from random, as a whole: data from the UK and other countries demonstrate that certain combinations are much more popular than average, and thus the skill to identify unpopular combinations can increase the mean return. Families of models of gambler choice are described, but, despite some encouraging indications, they all have significant deficiencies.
Simple Methods for Ecological Inference in 2×2 Tables
Authors: Chambers R. L. , Steel D. G. 
Published: March 2003

Summary
This paper considers inference about the individual level relationship between two dichotomous variables based on aggregated data. It is known that such analyses suffer from ‘ecological bias’, caused by the lack of homogeneity of this relationship across the groups over which the aggregation occurs. Two new methods for overcoming this bias, one based on local smoothing and the other a simple semiparametric approach, are developed and evaluated. The local smoothing approach performs best when it is used with a covariate which accounts for some of the variation in the relationships across groups. The semiparametric approach performed well in our evaluation even without such auxiliary information
Estimation of a Large Cross-Classified Multilevel Model to Study Academic Achievement in a Modular Degree Course
Authors: Simonite V. , Browne W. J. 
Published: March 2003

SummaryModular programmes are now the most popular framework for first-degree courses in the UK. Within a modular degree course, each student's programme consists of a number of modules taken in each term or semester. Detailed records of undergraduates’ performance are maintained throughout their programmes, allowing patterns of achievement to be studied. The data contained in students’ transcripts have a cross-classified structure, in which the marks recorded in each module entry are nested within students and also within modules. Models for cross-classified data can be computationally difficult, especially when large numbers of units are involved, but estimates can be obtained by using Markov chain Monte Carlo methods. In the context of modular higher education, it is important that such models can represent the effects of students’ backgrounds, and of the learning environments provided in each module on students’ mean levels of achievement and on variation at different levels of the model. This paper discusses models that are suitable for analysing student transcript data from a modular degree programme and describes an algorithm for fitting a cross-classified model that includes random effects and complex or heterogeneous variance functions. The results of applying this model to student transcript data for a first-degree course are used to demonstrate the importance of employing a cross-classified model and the value, in substantive terms, of the information that is obtained.
Statistical Studies of Infectious Disease Incidence
Authors: Becker N. G. , Britton T. 
Published: March 2003

Summary
Methods for the analysis of data on the incidence of an infectious disease are reviewed, with an emphasis on important objectives that such analyses should address and identifying areas where further work is required. Recent statistical work has adapted methods for constructing estimating functions from martingale theory, methods of data augmentation and methods developed for studying the human immunodeficiency virus–acquired immune deficiency syndrome epidemic. Infectious disease data seem particularly suited to analysis by Markov chain Monte Carlo methods. Epidemic modellers have recently made substantial progress in allowing for community structure and heterogeneity among individuals when studying the requirements for preventing major epidemics. This has stimulated interest in making statistical inferences about crucial parameters from infectious disease data for such community settings.
Discrete Approximations to Continuous Univariate Distributions—an Alternative to Simulation
Authors: Luceño A. 
Published: March 2003

Summary
A method to replace a continuous univariate distribution with a discrete distribution that takes MN different values is analysed. Both distributions share the same rth moments for r=0, . . ., 2N−1 and their corresonding distribution functions coincide at least at M+1 points. Several statistical and engineering examples are considered in which the discrete approximation may be used to avoid a simulation study that would be much more demanding computationally.
An Analysis of Swendsen–Wang and Related Sampling Methods
Authors: Fishman George S. 
Published: March 2003

Summary
Convergence rates, statistical efficiency and sampling costs are studied for the original and extended Swendsen–Wang methods of generating a sample path {S j, j≥1} with equilibrium distribution π, with r distinct elements, on a finite state space X of size N 1. Given S j-1, each method uses auxiliary random variables to identify the subset of X from which S j is to be randomly sampled. Let πmin and πmax denote respectively the smallest and largest elements in π and let Nr denote the number of elements in π with value πmax. For a single auxiliary variable, uniform sampling from the subset and (N 1−Nr)πmin+Nrπmax≈1, our results show rapid convergence and high statistical efficiency for large πmin/πmax or Nr/N 1 and slow convergence and poor statistical efficiency for small πmin/πmax and Nr/N1. Other examples provide additional insight. For extended Swendsen–Wang methods with non-uniform subset sampling, the analysis identifies the properties of a decomposition of π(x) that favour fast convergence and high statistical efficiency. In the absence of exploitable special structure, subset sampling can be costly regardless of which of these methods is employed.
Adaptive Weights Smoothing with Applications to Image Restoration
Authors: Polzehl Jöorg , Spokoiny V. G. 
Published: March 2003

Summary
We propose a new method of nonparametric estimation which is based on locally constant smoothing with an adaptive choice of weights for every pair of data points. Some theoretical properties of the procedure are investigated. Then we demonstrate the performance of the method on some simulated univariate and bivariate examples and compare it with other nonparametric methods. Finally we discuss applications of this procedure to magnetic resonance and satellite imaging.
Median Treatment Effect in Randomized Trials
Authors: Lee Myoung-jae 
Published: March 2003

Summary
For two response variables y t and y c corresponding to two treatments for two policies) T and C, we wish to learn about quantiles of y t−y c from the marginal quantiles of y t and y c; only one of y t and y c is observed for an individual. We find that, in general, this is difficult for quantiles other than the median unless strong assumptions are imposed on how y t is related to y c. For the median, we present conditions under which the sign of the median treatment effect is identified.
A Modified Likelihood Ratio Test for Homogeneity in Finite Mixture Models
Authors: Chen Hanfeng , Chen Jiahua , Kalbfleisch John D. 
Published: March 2003

Summary
Testing for homogeneity in finite mixture models has been investigated by many researchers. The asymptotic null distribution of the likelihood ratio test (LRT) is very complex and difficult to use in practice. We propose a modified LRT for homogeneity in finite mixture models with a general parametric kernel distribution family. The modified LRT has a χ-type of null limiting distribution and is asymptotically most powerful under local alternatives. Simulations show that it performs better than competing tests. They also reveal that the limiting distribution with some adjustment can satisfactorily approximate the quantiles of the test statistic, even for moderate sample sizes.
A Penalized Likelihood Approach to Image Warping
Authors: Glasbey C. A. , Mardia K. V. 
Published: March 2003

Summary
A warping is a function that deforms images by mapping between image domains. The choice of function is formulated statistically as maximum penalized likelihood, where the likelihood measures the similarity between images after warping and the penalty is a measure of distortion of a warping. The paper addresses two issues simultaneously, of how to choose the warping function and how to assess the alignment. A new, Fourier–von Mises image model is identified, with phase differences between Fourier-transformed images having von Mises distributions. Also, new, null set distortion criteria are proposed, with each criterion uniquely minimized by a particular set of polynomial functions. A conjugate gradient algorithm is used to estimate the warping function, which is numerically approximated by a piecewise bilinear function. The method is motivated by, and used to solve, three applied problems: to register a remotely sensed image with a map, to align microscope images obtained by using different optics and to discriminate between species of fish from photographic images.
Parametric Models for Response-Biased Sampling
Authors: Chen Kani 
Published: March 2003

Summary
Suppose that subjects in a population follow the model f(y*|x*;θ) where y* denotes a response, x* denotes a vector of covariates and θ is the parameter to be estimated. We consider response-biased sampling, in which a subject is observed with a probability which is a function of its response. Such response-biased sampling frequently occurs in econometrics, epidemiology and survey sampling. The semiparametric maximum likelihood estimate of θ is derived, along with its asymptotic normality, efficiency and variance estimates. The estimate proposed can be used as a maximum partial likelihood estimate in stratified response-selective sampling. Some computation algorithms are also provided.
Crossover Designs in the Presence of Carry-Over Effects from Two Factors
Authors: Lewis S. M. , Russell K. G. 
Published: March 2003

SUMMARY
Experiments, used in the telecommunications industry and elsewhere, are considered that involve the simultaneous application of levels of two unrelated factors, treatments and stimuli, to each of several subjects in a succession of time periods. The existence is suspected of carry-over effects of treatments and stimuli, in the period immediately following the period of their application. Methods are given for the construction of separate sequences of treatments and of stimuli; these methods are based on the Latin squares of Williams and of Russell. In the resulting designs, the treatments and stimuli are either orthogonal or nearly orthogonal, and the coincidence of the direct and carry-over effects of each factor is either balanced or nearly balanced. The efficiencies of the designs are assessed by comparing the average variances of elementary contrasts in the levels of each factor with appropriate lower bounds.
Sample Selection in Radiocarbon Dating
Authors: Christen J. Andrés , Buck Caitlin E. 
Published: March 2003

SUMMARY
Archaeologists working on the island of O’ahu, Hawai’i, use radiocarbon dating of samples of organic matter found trapped in fish-pond sediments to help them to learn about the chronology of the construction and use of the aquicultural systems created by the Polynesians. At one particular site, Loko Kuwili, 25 organic samples were obtained and funds were available to date an initial nine. However, on calibration to the calendar scale, the radiocarbon determinations provided date estimates that had very large variances. As a result, major issues of chronology remained unresolved and the archaeologists were faced with the prospect of another expensive programme of radiocarbon dating. This paper presents results of research that tackles the problems associated with selecting samples from those which are still available. Building on considerable recent research that utilizes Markov chain Monte Carlo methods to aid archaeologists in their radiocarbon calibration and interpretation, we adopt the standard Bayesian framework of risk functions, which allows us to assess the optimal samples to be sent for dating. Although rather computer intensive, our algorithms are simple to implement within the Bayesian radiocarbon framework that is already in place and produce results that are capable of direct interpretation by the archaeologists. By dating just three more samples from Loko Kuwili the expected variance on the date of greatest interest could be substantially reduced.
Empirical Bayes Estimation for Archaeological Stratigraphy
Authors: Allum G. T. , Aykroyd R. G. , Haigh J. G. B. 
Published: March 2003

SUMMARY
Models and algorithms are presented for the stratigraphic analysis of earth core samples collected at archaeological sites. The aim is to separate the occupation of the site into distinct periods, by dividing the earth core into well-defined blocks of uniform magnetic susceptibility. The models describe the response of detector equipment by using both a spread function and an error process, and they incorporate prior beliefs regarding the nature of the true susceptibility values. The prior parameters are estimated by using pseudolikelihood and the susceptibilities by maximum a posteriori methods via the one-step-late algorithm. These procedures are illustrated with data from synthetic and real core specimens. The new procedures prove to be far superior to other approaches, producing reconstructions which clearly show distinct periods of uniform magnetic susceptibility separated by sharp discontinuities.