Cross-Device Tracking: Matching Devices and Cookies

The number of computers, tablets and smartphones is increasing rapidly, which entails the ownership and use of multiple devices to perform online tasks. As people move across devices to complete these tasks, their identities becomes fragmented. Understanding the usage and transition between those devices is essential to develop efficient applications in a multi-device world. In this paper we present a solution to deal with the cross-device identification of users based on semi-supervised machine learning methods to identify which cookies belong to an individual using a device. The method proposed in this paper scored third in the ICDM 2015 Drawbridge Cross-Device Connections challenge proving its good performance

Artificial Neural Nets with Interaction of Afferents

The aim is to obtain computationally more powerful, neuro physiologically founded, artificial neurons and neural nets. Artificial Neural Nets (ANN) of the Perceptron type evolved from the original proposal by McCulloch an Pitts classical paper [1]. Essentially, they keep the computing structure of a linear machine followed by a non linear operation. The McCulloch-Pitts formal neuron (which was never considered by the author’s to be models of real neurons) consists of the simplest case of a linear computation of the inputs followed by a threshold. Networks of one layer cannot compute anylogical function of the inputs, but only those which are linearly separable. Thus, the simple exclusive OR (contrast detector) function of two inputs requires two layers of formal neuron

Towards a Reliable Comparison and Evaluation of Network Intrusion Detection Systems Based on Machine Learning Approaches

Presently, we are living in a hyper-connected world where millions of heterogeneous devices are continuously sharing information in different application contexts for wellness, improving communications, digital businesses, etc. However, the bigger the number of devices and connections are, the higher the risk of security threats in this scenario. To counteract against malicious behaviours and preserve essential security services, Network Intrusion Detection Systems (NIDSs) are the most widely used defence line in communications networks. Nevertheless, there is no standard methodology to evaluate and fairly compare NIDSs. Most of the proposals elude mentioning crucial steps regarding NIDSs validation that make their comparison hard or even impossible. This work firstly includes a comprehensive study of recent NIDSs based on machine learning approaches, concluding that almost all of them do not accomplish with what authors of this paper consider mandatory steps for a reliable comparison and evaluation of NIDSs. Secondly, a structured methodology is proposed and assessed on the UGR'16 dataset to test its suitability for addressing network attack detection problems. The guideline and steps recommended will definitively help the research community to fairly assess NIDSs, although the definitive framework is not a trivial task and, therefore, some extra effort should still be made to improve its understandability and usability further

Rentier States and Geography in Mexico's Development

This paper provides a long-term historical and econometric account of the way in which geography has shaped development in the Mexican states. The emphasis is placed on the way in which the natural geography is reinforced by political decisions, which configure the human geography of population density, urbanization and public good provision, which in turn determine income, growth and poverty. The paper presents brief historical instances of how geography has determined prospects for development at different moments in Mexican history. This anecdotal discussion seeks to highlight the intrinsic link of geography with political institutions, which is central to understanding the economic effects of geography. The paper then presents a descriptive statistical and geographical profile of the relationship between geography and development in Mexico. The paper argues that the main channel through which geography affects development is political. The fragmentation of political jurisdictions in the form of municipal governments constitutes a proxy for man-made barriers to geographic mobility, which explain the interaction between geography, politics and development.

A photometric comprehensive study of circumnuclear star forming rings: the sample

We present photometry in U, B, V, R and I continuum bands and in H$\alpha$ and H$\beta$ emission lines for a sample of 336 circumnuclear star forming regions (CNSFR) located in early type spiral galaxies with different levels of activity in their nuclei. They are nearby galaxies, with distances less than 100 Mpc, 60\% of which are considered as interacting objects. This survey of 20 nuclear rings aims to provide insight into their star formation properties as age, stellar population and star formation rate. Extinction corrected H$\alpha$ luminosities range from $1.3\times 10^{38}$ to $4\times 10^{41} erg s^{-1}$, with most of the regions showing values between 39.5 $\leq log L(H\alpha) \leq$ 40, which implies masses for the ionizing clusters higher than $2\times 10^{5} M_\odot$. H$\alpha$ and H$\beta$ images have allowed us to obtain an accurate measure of extinction. We have found an average value of A$_V$ = 1.85 magnitudes. (U-B) colour follows a two maximum distribution around (U-B)$\simeq$ -0.7, and -0.3; (R-I) also presents a bimodal behaviour, with maximum values of 0.6 and 0.9. Reddest (U-B) and (R-I) regions appear in non-interacting galaxies. Reddest (R-I) regions lie in strongly barred galaxies. For a significant number of HII regions the observed colours and equivalent widths are not well reproduced by single burst evolutionary theoretical models.Comment: Accepted for publication in MNRAS. Accepted 15 May 2015. Received, 21 April 201

La didáctica de la historia en la Universidad : el reino de la nada

El present article és una conferència que es va dictar a las "1as Jornades de Didàtica de la Història al Batxillerat" organitzades per l'ICE de la Universitat de Barcelona. Així mateix va ser llegida també a la Universitat Autònoma de Barcelona. Pel seu interés hem cregut convenient publicar-la a Manuscrits