Search for dissertations about: "Xavier De Luna"

Showing result 1 - 5 of 16 swedish dissertations containing the words Xavier De Luna.

  2. 1. Prediction Methods for High Dimensional Data with Censored Covariates

    Author : Caroline Svahn; Oleg Sysoev; Mattias Villani; Fredrik Gunnarsson; Xavier de Luna; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; statistics; machine learning; censored covariates; statistik; maskininlärning; censurerade kovariater;

    Abstract : While access to data steadily increases, not all data are straight-forward to use for prediction. Censored data are common in several industrial scenarios, and typically arise when there are some limitations to measuring equipment such as for instance concentration measuring equipment in chemistry or signal receivers in signal processing. READ MORE

  4. 2. Active and healthy ageing in Europe : significance of social relationships

    Author : Septi Kurnia Lestari; Nawi Ng; Xavier de Luna; Malin Eriksson; Mikael Rostila; Umeå universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; older population; ageing; social relationships; social support; social participation; social contact; quality of life; frailty; panel data; latent class analysis; growth model; multilevel logistic regression; pandemic; Europe; SHARE; äldre befolkning; åldrande; sociala relationer; socialt stöd; socialt deltagande; sociala kontakter; livskvalitet; åldersskörhet; paneldata; latent klassanalys; tillväxtmodell; flernivålogistisk regression; pandemi; Europa; SHARE; epidemiologi; Epidemiology; Public health; folkhälsa;

    Abstract : Background: Social relationships have important roles in achieving active and healthy ageing. Social relationships are dynamic across the life course. A myriad of contextual and individual (e.g. READ MORE

  5. 3. Observed score equating with covariates

    Author : Kenny Bränberg; Marie Wiberg; Xavier de Luna; Dag Sörbom; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Equating; observed score equating; true scores; item response theory; linear equating function; equipercentile equating; kernel equating; covariates; linear regression; mean squared error; Statistics; Statistik; Statistics; statistik;

    Abstract : In test score equating the focus is on the problem of finding the relationship between the scales of different test forms. This can be done only if data are collected in such a way that the effect of differences in ability between groups taking different test forms can be separated from the effect of differences in test form difficulty. READ MORE

  6. 4. Studying earnings trajectories as functional outcomes

    Author : Kreske Ecker; Xavier de Luna; Lina Schelin; Jose Peña; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; functional data analysis; causal inference; earnings trajectories; simultaneous confidence bands; missing data; Statistics; statistik;

    Abstract : In this thesis, we present methods for studying patterns of income accumulation over time using functional data analysis. This is made possible by the availability of large-scale longitudinal register data in Sweden. READ MORE

  7. 5. Modeling financial volatility : A functional approach with applications to Swedish limit order book data

    Author : Suad Elezovic; Xavier de Luna; Gunnar Rosenqvist; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Financial data; functional time series; multivariate generalized least squares; seemingly unrelated autoregression; Statistics; computer and systems science; Statistik; data- och systemvetenskap; ekonometri; Econometrics;

    Abstract : This thesis is designed to offer an approach to modeling volatility in the Swedish limit order market. Realized quadratic variation is used as an estimator of the integrated variance, which is a measure of the variability of a stochastic process in continuous time. READ MORE