Evans functions for integral neural field equations with Heaviside firing rate function

In this paper we show how to construct the Evans function for traveling wave solutions of integral neural field equations when the firing rate function is a Heaviside. This allows a discussion of wave stability and bifurcation as a function of system parameters, including the speed and strength of synaptic coupling and the speed of axonal signals. The theory is illustrated with the construction and stability analysis of front solutions to a scalar neural field model and a limiting case is shown to recover recent results of L. Zhang [On stability of traveling wave solutions in synaptically coupled neuronal networks, Differential and Integral Equations, 16, (2003), pp.513-536.]. Traveling fronts and pulses are considered in more general models possessing either a linear or piecewise constant recovery variable. We establish the stability of coexisting traveling fronts beyond a front bifurcation and consider parameter regimes that support two stable traveling fronts of different speed. Such fronts may be connected and depending on their relative speed the resulting region of activity can widen or contract. The conditions for the contracting case to lead to a pulse solution are established. The stability of pulses is obtained for a variety of examples, in each case confirming a previously conjectured stability result. Finally we show how this theory may be used to describe the dynamic instability of a standing pulse that arises in a model with slow recovery. Numerical simulations show that such an instability can lead to the shedding of a pair of traveling pulses.

CAUSAL INFERENCE WITH A CONTINUOUS TREATMENT AND OUTCOME: ALTERNATIVE ESTIMATORS FOR PARAMETRIC DOSE-RESPONSE FUNCTIONS WITH APPLICATIONS.

Causal inference with a continuous treatment is a relatively under-explored problem. In this dissertation, we adopt the potential outcomes framework. Potential outcomes are responses that would be seen for a unit under all possible treatments. In an observational study where the treatment is continuous, the potential outcomes are an uncountably infinite set indexed by treatment dose. We parameterize this unobservable set as a linear combination of a finite number of basis functions whose coefficients vary across units. This leads to new techniques for estimating the population average dose-response function (ADRF). Some techniques require a model for the treatment assignment given covariates, some require a model for predicting the potential outcomes from covariates, and some require both. We develop these techniques using a framework of estimating functions, compare them to existing methods for continuous treatments, and simulate their performance in a population where the ADRF is linear and the models for the treatment and/or outcomes may be misspecified. We also extend the comparisons to a data set of lottery winners in Massachusetts. Next, we describe the methods and functions in the R package causaldrf using data from the National Medical Expenditure Survey (NMES) and Infant Health and Development Program (IHDP) as examples. Additionally, we analyze the National Growth and Health Study (NGHS) data set and deal with the issue of missing data. Lastly, we discuss future research goals and possible extensions.

Rapport sur le fonctionnement du Service Océanographique des Pêches de L'Indochine pendant l'année 1926-1927

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1926-1927.

Rapport sur le fonctionnement du Service Océanographique des Pêches de l'Indochine pendant l'année 1927-1928

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1927-1928.

Rapport sur le fonctionnement du Service Océanographique des Pêches de l'Indochine pendant l'année 1928-1929

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1928-1929.

Rapport sur le fonctionnement du l'Institut Océanographique de l'Indochine pendant l'année 1929-1930

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1929-1930.

Rapport sur le fonctionnement du l'Institut Océanographique de l'Indochine pendant l'année 1930-1931

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1930-1931.

Rapport sur le fonctionnement du l'Institut Océanographique de l'Indochine pendant l'année 1931-1932

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1931-1932.

Rapport sur le fonctionnement de l'Institut Océanographique de l'Indochine pendant l'année 1932-1933

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1932-1933.

Rapport sur le fonctionnement du l'Institut Océanographique de l'Indochine pendant l'année 1933-1934

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1933-1934.

Rapport sur le fonctionnement de l'Institut Océanographique de l'Indochine pendant l'année 1934-1935

The present note deals with the functions and activities done by the Institute of oceanography of Indochina during 1934-1935.

Essays on educational production functions in England

Despite the expansion of the literature on the implications that different inputs have on the educational outcomes of students, empirical research has so far lacked the full capacity to provide unequivocal findings. Essentially, this deficiency is mainly attributed to two main factors; the lack of reliable data and the lack of full dimensionality in the theoretical model adopted to explain such data (Levaččićć and Vignoles, 2002; Knoeppel, Verstegen, and Rinehart, 2007). This dissertation aims to fill those gaps by first building a unique large dataset that covers all aspects of the educational process and second by adopting an integrated theoretical model and advanced quantitative methodological approaches to analyze it. With the fulfillment of such aim the dissertation manages to fill some of the gaps identified in the Education Economics literature related to the relationships between the cognitive and affective educational outcomes of English adolescents on one hand and three main inputs representing each of the three indentified factors in the theoretical model on the other hand controlling for other possible heterogeneities. Specifically, the thesis examines the effect of school process inputs in Chapter 2, family structure as a key family background input in Chapter 3 and finally religion and religiosity as a key adolescent’s personal input in Chapter 4.

Rapport sur le fonctionnement de l'Institut Océanographique de l'Indochine pendant l'année 1935-1936

The present note deals with the functions and activities carried out by the Institute of oceanography of Indochina during 1935-1936

Rapport sur le fonctionnement de l'Institut Océanographique de l'Indochine pendant l'année 1936-1937

The present note deals with the functions and activities carried out by the Institute of oceanography of Indochina during 1936-1937

Rapport sur le fonctionnement de l'Institut Océanographique de l'Indochine pendant l'année 1937-1938

The present note deals with the functions and activities carried out by the Institute of oceanography of Indochina during 1937-1938