Publications des institutions partenaires

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Robust Estimation for Bivariate Distribution

Copula functions are very convenient for modelling multivariate observations. Popular estimation methods are the two-stage MLE and an alternative semi-parametric with empirical cdf for the margins. Unfortunately, they are hastily biased whenever relatively small model deviations occur at the marginal (empirical or parametric) and/or copula levels. In this master thesis we propose...

Institution partenaire

Université de Genève

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English / 01/01/2013

Economic Theory and Minority Language

Institution partenaire

Université de Genève

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English / 01/01/2013

Wavelet-Variance-Based Estimation for Composite Stochastic Processes

This article presents a new estimationmethod for the parameters of a times series model.We consider here composite Gaussian processes that are the sum of independent Gaussian processes which, in turn, explain an important aspect of the time series, as is the case in engineering and natural sciences. The proposed estimation method offers an alternative to classical estimation based on...

Institution partenaire

Université de Genève

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English / 01/01/2013

Fault Detection and Isolation in Multiple MEMS-IMUs Configurations

This research presents methods for detecting and isolating faults in multiple MEMS-IMU configurations. First, geometric configurations with n sensor triads are investigated. It is proofed that the relative orientation between sensor triads is irrelevant to system optimality in the absence of failures. Then, the impact of sensor failure or decreased performance is investigated. Three...

Institution partenaire

Université de Genève

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English / 01/01/2012

A Prediction Divergence Criterion for Model Selection

In this paper, we propose a new criterion for selection between nested models. We suppose that the correct model is one (or near one) of the available models and construct a criterion which is based on the Bregman divergence between the out-of-sample prediction of the smaller model and the in-sample prediction of the larger model. This criterion, the prediction divergence criterion (...

Institution partenaire

Université de Genève

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English / 01/01/2012

A Framework for Inertial Sensor Calibration using Complex Stochastic Error Models, in the proceedings of the Position Location and Navigation Symposium (PLANS), 2012 IEEE/ION

Modeling and estimation of gyroscope and accelerometer errors is generally a very challenging task, especially for low-cost inertial MEMS sensors whose systematic errors have complex spectral structures. Consequently, identifying correct error-state parameters in a INS/GNSS Kalman filter/smoother becomes difficult when several processes are superimposed. In such situations, the...

Institution partenaire

Université de Genève

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English / 01/01/2012

Robust filtering

Filtering methods are powerful tools to estimate the hidden state of a statespace model from observations available in real time. However, they are known to be highly sensitive to the presence of small misspecifications of the underlying model and to outliers in the observation process. In this paper, we show that the methodology of robust statistics can be adapted to sequential...

Institution partenaire

Université de Genève

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English / 01/01/2012

Fast Robust Model Selection in Large Datasets

Large datasets are more and more common in many research fields. In particular, in the linear regression context, it is often the case that a huge number of potential covariates are available to explain a response variable, and the first step of a reasonable statistical analysis is to reduce the number of covariates. This can be done in a forward selection procedure that includes the...

Institution partenaire

Université de Genève

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English / 01/01/2011

Isotone additive latent variable models

For manifest variables with additive noise and for a given number of latent variables with an assumed distribution, we propose to nonparametrically estimate the association between latent and manifest variables. Our estimation is a two step procedure: first it employs standard factor analysis to estimate the latent variables as theoretical quantiles of the assumed distribution;...

Institution partenaire

Université de Genève

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English / 01/01/2011

Constrained Expectation-Maximization Algorithm for Stochastic Inertial Error Modeling: Study of Feasibility

Stochastic modeling is a challenging task for low-cost sensors which errors can have complex spectral structures. This makes the tuning process of the INS/GNSS Kalman filter often sensitive and diffcult. For example, first-order Gauss-Markov processes are very often used in inertial sensor models. But the estimation of their parameters is a non-trivial task if the error structure is...

Institution partenaire

Université de Genève

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English / 01/01/2011

Generalized Method of Wavelet Moments

This paper presents a new estimation method for the parameters of a model generating times series. Given some conditions on the form of the power spectral density associated to the process, it is possible to indirectly recover pa- rameter estimates from wavelet variances (WV) associated to the process. We propose an optimization criterion based on a standardized distance between the...

Institution partenaire

Université de Genève

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English / 01/01/2011

Statistical modelling of radio audience data: a parametric approach

In this thesis, we develop models to analyze zero-inflated truncated heavy-tailed dependent data to fit radio audience data in Switzerland. These models are able to explain, by means of covariates, both the probability of observing a positive outcome and the mean of the positive outcomes, which respectively correspond to the audience indicators of reach and of time spent listening....

Institution partenaire

Université de Genève

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English / 01/01/2011

Robust VIF Regression

The sophisticated and automated means of data collection used by an increasing number of institutions and companies leads to extremely large datasets. Subset selection in regression is essential when a huge number of covariates can potentially explain a response variable of interest. The recent statistical literature has seen an emergence of new selection methods that provide some...

Institution partenaire

Université de Genève

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English / 01/01/2011

Improving Modeling of MEMS-IMUs Operating in GNSS-denied Conditions

Stochastic modeling is a challenging task for lowcost inertial sensors whose errors can have complex spectral structures. This makes the tuning process of the INS/GNSS Kalman filter often sensitive and difficult. We are currently investigating two approaches for bounding the errors in the mechanization. The first is an improved modeling of stochastic errors through the superposition...

Institution partenaire

Université de Genève

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English / 01/01/2011

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