21 research outputs found
¿Cómo cerrar el cÃrculo de la innovación? Abriéndolo
Recuerdo la primera vez que vi la tercera "i", en minúscula, acompañando a las letras I + D, las ya conocidas como "Investigación+ Desarrollo". Me sorprendió, no sabÃa qué significaba, y me sentÃa que no iba al ritmo de los tiempos. El nuevo mantra era ahora la I + D+ i. La idea detrás de esa nueva letra era que los resultados de investigación no debÃan quedarse en el centro que los generara (universidad, instituto de investigación), sino que habÃa que intentar transferir esos resultados a la sociedad, sacarlos del cajón del investigador, y permitir que fueran de provecho general. Esto normalmente se hace a través de empresas, que se encargan de productizar y comercializar el resultado de investigación
On the distribution of source code file sizes
Source code size is an estimator of software effort. Size is also often used to calibrate models and equations to estimate the cost of software. The distribution of source code file sizes has been shown in the literature to be a lognormal distribution. In this paper, we measure the size of a large collection of software (the Debian GNU/Linux distribution version 5.0.2), and we find that the statistical distribution of its source code file sizes follows a double Pareto distribution. This means that large files are to be found more often than predicted by the lognormal distribution, therefore the previously proposed models underestimate the cost of software
A quantitative examination of the impact of featured articles in Wikipedia
This paper presents a quantitative examination of the impact of the presentation of featured articles as quality content in the main page of several Wikipedia editions. Moreover, the paper also presents the analysis performed to determine the number of visits received by the articles promoted to the featured status. We have analyzed the visits not only in the month when articles awarded the promotion or were included in the main page, but also in the previous and following ones. The main aim for this is to assess the attention attracted by the featured content and the different dynamics exhibited by each community of users in respect to the promotion process. The main results of this paper are twofold: it shows how to extract relevant information related to the use of Wikipedia, which is an emerging research topic, and it analyzes whether the featured articles mechanism achieve to attract more attention
Temporal characterization of the requests to Wikipedia
This paper presents an empirical study about the temporal patterns
characterizing the requests submitted by users to Wikipedia.
The study is based on the analysis of the log lines registered by the
Wikimedia Foundation Squid servers after having sent the appropriate
content in response to users' requests. The
analysis has been conducted regarding the ten most visited editions of
Wikipedia and has involved more than 14,000 million log lines
corresponding to the traffic of the entire year 2009. The conducted methodology
has mainly consisted in the parsing and filtering
of users' requests according to the study directives. As a result, relevant information
fields have been finally stored in a database for persistence and further
characterization. In this way, we, first, assessed, whether the traffic to Wikipedia could serve
as a reliable estimator of the overall traffic to all the Wikimedia Foundation
projects. Our subsequent analysis of the temporal evolutions corresponding to
the different types of requests to Wikipedia revealed interesting differences
and similarities among them that can be related to the users' attention to the Encyclopedia.
In addition, we have performed separated characterizations of each Wikipedia edition
to compare their respective evolutions over time
Studying the laws of software evolution in a long-lived FLOSS project
ome free, open-source software projects have been around for quite a long time, the longest living ones dating from the early 1980s. For some of them, detailed information about their evolution is available in source code management systems tracking all their code changes for periods of more than 15 years. This paper examines in detail the evolution of one of such projects, glibc, with the main aim of understanding how it evolved and how it matched Lehman's laws of software evolution. As a result, we have developed a methodology for studying the evolution of such long-lived projects based on the information in their source code management repository, described in detail several aspects of the history of glibc, including some activity and size metrics, and found how some of the laws of software evolution may not hold in this cas
Do Subsidies Provided to Public Transport in Madrid Favor Vertical Equity?
Despite the widespread implementation of subsidy policies for urban transport in many cities, the equity evaluation of these policies still remains limited. There is scarce quantitative assessment of the distributional incidence of transport subsidy policies. This paper contributes to fill this research gap by developing a practical approach to evaluate the impact of fare subsidization on vertical equity. In the paper we implement a two-step methodology. First, we develop two main indicators to measure the social impacts of the ?travel pass?, which is a highly subsidized fare in order to examine the policy for its effectiveness in reaching the poor. Second, by using the latest disaggregated data from Madrid?s Transportation Survey, we fitted a multiple regression model which found out that the use of the travel pass depends fundamentally on income level and accessibility to public transport. Since the quality of accessibility in the city is quite homogeneous, the subsidy policy associated with the travel pass is shown to be progressive because it is well targeted towards economically disadvantaged groups. Consequently, there seems to be evidence that subsidies provided to public transport in Madrid tend to favor vertical equity
Characterization of the Wikipedia Traffic
Since its inception, Wikipedia has grown to a solid and stable project and turned into a mass collaboration tool that allows the sharing and distribution of knowledge. The wiki approach that basis this initiative promotes the participation and collaboration of users. In addition to visits for browsing its contents, Wikipedia also receives the contributions of users to improve them. In the past, researchers paid attention to different aspects concerning authoring and quality of contents. However, little effort has been made to study the nature of the visits that Wikipedia receives. We conduct such an study using a sample of users' requests provided by the Wikimedia Foundation in the form of Squid log lines. Our sample contains more that 14,000 million requests from users all around the world and directed to all the projects maintained by the Wikimedia Foundation, including different editions of Wikipedia. This papers describes the work made to characterize the traffic directed to Wikipedia and consisting of the requests sent by its users. Our main aim is to obtain a detailed description of its composition in terms of the percentages corresponding to the different types of requests making part of it. The benefits from our work may range from the prediction of traffic peaks to the determination of the kind of resources most often requested, which can be useful for scalability considerations
The evolution of the laws of software evolution. A discussion based on a systematic literature review
After more than 40 years of life, software evolution should be considered as a mature field. However, despite
such a long history, many research questions still remain open, and controversial studies about the validity
of the laws of software evolution are common. During the first part of these 40 years the laws themselves
evolved to adapt to changes in both the research and the software industry environments. This process
of adaption to new paradigms, standards, and practices stopped about 15 years ago, when the laws were
revised for the last time. However, most controversial studies have been raised during this latter period.
Based on a systematic and comprehensive literature review, in this paper we describe how and when the
laws, and the software evolution field, evolved. We also address the current state of affairs about the validity
of the laws, how they are perceived by the research community, and the developments and challenges that
are likely to occur in the coming years
Social and Distributional Effects of Public Transport Fares and Subsidy Policies: Case of Madrid
Despite the widespread implementation of urban transport subsidies in many cities, there are still only a limited evaluation of the equity of these policies and scarce quantitative assessment of their distributional incidence. This research contributes to filling this gap by developing a practical approach to evaluate the impact of fare subsidization on vertical equity. This paper implements a two-step methodology. First, two main indicators were developed to measure the social impact of the travel pass, a highly subsidized fare, to determine the effectiveness of the policy in reaching lower-income citizens. Second, by using the latest disaggregated data from a transportation survey, in Madrid, Spain, a multiple regression model revealed that travel pass usage (TPU) depended mainly on income level and accessibility to public transport. The results show that the accessibility level has a positive effect on the TPU indicator, whereas income level has a negative influence. Because income level is shown to play the most significant role in influencing public transport use, the subsidy policy associated with the travel pass in the city can be considered progressive, since it effectively targets economically disadvantaged groups. This fact suggests that subsidies for public transport in Madrid tend to favor vertical equity
Lighter Than Air: An Interview with Carol Mavor, The Ambiguity of the Edwardian Boy
In the last decade, a large number of software repositories have been created for different purposes. In this paper we present a survey of the publicly available repositories and classify the most common ones as well as discussing the problems faced by researchers when applying machine learning or statistical techniques to them