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In this paper, I introduce the longitudinal method in general, and more specifically, the method applied in a two-decade-long language shift research project conducted in a Romanian–Hungarian bilingual village, Ketegyhaza (hereinafter LongBiLing: longitudinal study on bilingualism). I will primarily present the language choice changes occurring in the first decade (1990–2001) but I will also give a short review of the findings comparing the two decades. The aim of the project is to find out at what stage the Romanian-Hungarian language shift process is in the Hamers and Blanc’s (1989) unidimensional model of language shift and to what extent the process can be considered gradual (Mesthrie 2001). In a previous article I sought to find out in which bilingual national minority (out of the six) in Hungary sustainable bilingualism was the strongest (Borbely 2015). In this paper, I discuss language use domains (25 language choice situations) in a local community of Hungary’s Romanian national minority investiga...

In this paper we propose a novel method for the segmentation of longitudinal brain MRI scans of patients suffering from Multiple Sclerosis. The method builds upon an existing cross-sectional method for simultaneous whole-brain and lesion segmentation, introducing subject-specific latent variables to encourage temporal consistency between longitudinal scans. It is very generally applicable, as it does not make any prior assumptions on the scanner, the MRI protocol, or the number and timing of longitudinal follow-up scans. Preliminary experiments on three longitudinal datasets indicate that the proposed method produces more reliable segmentations and detects disease effects better than the cross-sectional method it is based upon.

This paper investigates the effect of the calculation of the longitudinal location of a wheel rail contact point on the wheelset’s motion in a vehicle dynamic simulation. All current vehicle dynamic software programs assume that the contact between wheel and rail takes place in the vertical plane through the wheelset’s rolling axis. However, when the yaw angle of the wheelset is nonzero, the contact point is situated up to 10 mm from that plane. This difference causes a difference in the yaw moment on the wheelset which is used in the vehicle dynamic simulation. To such an end, an existing analytical method to determine the longitudinal method was validated using a numerical approach. Then vehicle dynamic simulations with both the classic and the new contact location were performed, concluding that using a more accurate contact point location results in a smaller wheelset yaw angle in a vehicle dynamic simulation, although the effect is small.

In the health and social sciences, longitudinal data have often been analyzed without taking into account the dependence between observations of the same subject. Furthermore, consideration is rarely given to the fact that longitudinal data may come from a non-normal distribution. In addition to describing the aims and types of longitudinal designs this paper presents three approaches based on generalized estimating equations that do take into account the lack of independence in data, as well as the type of distribution. These approaches are the marginal model (population-average model), the random effects model (subject-specific model), and the transition model (Markov model or auto-correlation model). Finally, these models are applied to empirical data by means of specific procedures included in SAS, namely GENMOD, MIXED, and GLIMMIX.

Understanding and predicting behavior in organizations requires a consideration of person and situation factors, and how these factors interact. This paper develops and longitudinally tests a model...

This paper reports a five-year longitudinal study of the management selection and allocation process in a specific, industrial R&D laboratory. Predictors included intelligence measures, interest pa...

This is the first of a series of papers designed to report the various stages of a longitudinal research project on the study of managerial effectiveness. The purposes of this article are: (1) to s...