Search results for " serie"
showing 10 items of 760 documents
Numerical Recovery of Source Singularities via the Radiative Transfer Equation with Partial Data
2013
The inverse source problem for the radiative transfer equation is considered, with partial data. Here we demonstrate numerical computation of the normal operator $X_{V}^{*}X_{V}$ where $X_{V}$ is the partial data solution operator to the radiative transfer equation. The numerical scheme is based in part on a forward solver designed by F. Monard and G. Bal. We will see that one can detect quite well the visible singularities of an internal optical source $f$ for generic anisotropic $k$ and $\sigma$, with or without noise added to the accessible data $X_{V}f$. In particular, we use a truncated Neumann series to estimate $X_{V}$ and $X_{V}^{*}$, which provides a good approximation of $X_{V}^{*…
How news affect the trading behavior of different categories of investors in a financial market
2015
We investigate the trading behavior of a large set of single investors trading the highly liquid Nokia stock over the period 2003-2008 with the aim of determining the relative role of endogenous and exogenous factors that may affect their behavior. As endogenous factors we consider returns and volatility, whereas the exogenous factors we use are the total daily number of news and a semantic variable based on a sentiment analysis of news. Linear regression and partial correlation analysis of data show that different categories of investors are differently correlated to these factors. Governmental and non profit organizations are weakly sensitive to news and returns or volatility, and, typica…
Ohjeita Jyväskylän yliopistosarjojen kirjoittajille :
2010
This document about the guidelines for publishing dissertation is out of date. Updated information is available in the webpage of Publishing Unit: https://kirjasto.jyu.fi/publish-and-buy/publishing-your-dissertation?set_language=en Tämä väitöskirjajulkaisemista käsittelevä dokumentti on vanhentunut. Ajanmukaiset väitöskirjajulkaisemista Jyväskylän yliopistossa koskevat ohjeet löydät Avoimen tiedon keskuksen julkaisuyksikön sivuilta https://kirjasto.jyu.fi/julkaisut/vaitoskirjojen-julkaisu
Qualitative analysis of housing demand using Google trends data
2019
Big data analytics often refer to the breakdown of huge amounts of data into a more readable and useful format. This study utilises Google Trends big data as a proxy for an analysis of housing demand. We employ a qualitative method (fuzzy set/Qualitative Comparative Analysis, fsQCA), instead of a quantitative method, for our estimate and forecast. The empirical results show that fsQCA successfully forecasts seasonal time series, even though the dataset is small in size. Our findings fill the gap in the qualitative and time series forecasting literature, and the forecasting procedure herein also offers a good standard for industry.
A hard day's night : the aftermath of psychological trauma in Grey's Anatomy
2014
Tämän tutkimuksen tarkoituksena oli tunnistaa ja kuvata tapoja, joilla fiktiiviset henkilöhahmot amerikkalaisessa sairaalasarjassa Greyn Anatomia reagoivat psykologisesti traumaattisiin kokemuksiin, sekä sitä, millainen rooli hahmojen keskinäisellä ystävyyssuhteella on parantumisprosessissa. Analyysin kohteena oli sarjan kaksi keskeistä henkilöhahmoa, Meredith Grey sekä Cristina Yang. Aineisto koostui kahdesta erillisestä tarinakaaresta: molemmat alkoivat traumaattisesta tapahtumasta ja loppuivat molempien hahmojen ns. löydettyä ratkaisun trauman aiheuttamiin ongelmiinsa. Yhteensä analysoituja jaksoja oli kuusitoista (16). Laadullisen analyysin perustana käytettiin kriittistä televisiotutki…
Defining polycentric urban areas through commuting cohesion. Through commuting cohesion in France
2013
International audience; Though the visualization of the daily commuting patterns around French urban area, we identify subcentres of commuting activities, illustrating the emergence of new urban polycentric structures. Via computed metrics on these graphs and an associated diachronic approach on the census data for the years between 1975 and 1999, we analyze the topological structure of the graph series. This analysis demonstrates the combined small world and star topology present in the data.
Identifying the Sales Patterns of Online Stores with Time Series Clustering
2018
Electronic commerce, especially in the business-to-consumer (B2C) context, has for years been a popular research topic in information systems (IS). However, the prior research on the topic has traditionally been dominated by the consumer focus instead of the business focus of online stores. For example, whereas various segmentations exist for online consumers based on their purchase behaviour, no such segmentations have been developed for online stores based on their sales patterns. In this study, our objective is to address this gap in prior research by identifying the most typical sales patterns of online stores operating in the B2C context. By using self-organising maps (SOM) to analyse …
Univariate and multivariate properties of wind velocity time series
2009
We analyze the time series of hourly average wind speeds measured at 29 different stations located in Sicily, a region with a complex morphology. The investigation, performed from the univariate as well as the multivariate point of view, evidences that the statistical properties of wind at the single sites have features that are not reproduced by standard models and, thus, require specific modeling. Moreover, the synchronous evolution of wind velocity presents a cluster structure, obtained with different algorithms, that persists in the standard deviation too.
Mise en évidence d'un Sénonien gypseux sous la série phosphatée du bassin des Ouled Abdoun: un nouveau point de départ pour l'origine des zones déran…
2013
In the Ouled Abdoun sedimentary basin (Morocco), the phosphatic series is composed of regular interbedded phosphatic and marly limestone layers. Exploitation of the phosphate in some deposits in this basin collides frequently with problems bound to the existence, in the phosphatic series, of disturbed areas (sterile bodies) qualified as derangements by the mining engineers of the Office Cherifian Phosphate Group (OCP). Their presence in the phosphatic layers causes two kinds of problems: (1) since the whole phosphatic sequence is overlain by a Quaternary cover, we do not know their volume proportion in the phosphatic layers, and therefore the reserves estimations can be wrong (2) they are g…