@article {1746,
	title = {Evaluation of FLOSS by Analyzing Its Software Evolution:},
	journal = {Journal of Information Technology Research},
	volume = {8},
	year = {2015},
	month = {01/2015},
	pages = {62 - 81},
	abstract = {In today{\textquoteright}s world, management often rely on FLOSS (Free/Libre/Open Source Software) systems to run their organizations. However, the nature of FLOSS is different from the software they have been using in the last decades. Its development model is distributed, and its authors are diverse as many volunteers and companies may collaborate in the project. In this paper, we want to shed some light on how to evaluate a FLOSS system by looking at the Moodle platform, which is currently the most used learning management system among educational institutions worldwide. In contrast with other evaluation models that have been proposed so far, the one we present is based on retrieving historical information that can be obtained publicly from the Internet, allowing us to study its evolution. As a result, we will show how by using our methodology management can take informed decisions that lower the risk that organizations face when investing in a FLOSS system.  },
	keywords = {free software, LMS, moodle, open source, software engineering, software evaluation, software evolution},
	issn = {1938-7865},
	doi = {10.4018/JITR.2015010105},
	attachments = {https://flosshub.org/sites/flosshub.org/files/Evaluation\%20of\%20FLOSS\%20by\%20Analyzing\%20its\%20Software\%20Evolution\%20-\%20An\%20Example\%20Using\%20the\%20Moodle\%20Platform.pdf},
	author = {Macho, H{\'e}ctor J. and Gregorio Robles and Gonz{\'a}lez-Barahona, Jesus M}
}
@conference {Robles:2014:EDE:2597073.2597107,
	title = {Estimating Development Effort in Free/Open Source Software Projects by Mining Software Repositories: A Case Study of OpenStack},
	booktitle = {Proceedings of the 11th Working Conference on Mining Software Repositories},
	series = {MSR 2014},
	year = {2014},
	pages = {222{\textendash}231},
	publisher = {ACM},
	organization = {ACM},
	address = {New York, NY, USA},
	abstract = {Because of the distributed and collaborative nature of free / open source software (FOSS) projects, the development effort invested in a project is usually unknown, even after the software has been released. However, this information is becoming of major interest, especially ---but not only--- because of the growth in the number of companies for which FOSS has become relevant for their business strategy. In this paper we present a novel approach to estimate effort by considering data from source code management repositories. We apply our model to the OpenStack project, a FOSS project with more than 1,000 authors, in which several tens of companies cooperate. Based on data from its repositories and together with the input from a survey answered by more than 100 developers, we show that the model offers a simple, but sound way of obtaining software development estimations with bounded margins of error.
},
	keywords = {effort estimation, free software, mining software repositories, open source, openstack},
	isbn = {978-1-4503-2863-0},
	doi = {10.1145/2597073.2597107},
	url = {http://doi.acm.org/10.1145/2597073.2597107},
	attachments = {https://flosshub.org/sites/flosshub.org/files/robles_0.pdf},
	author = {Gregorio Robles and Gonz{\'a}lez-Barahona, Jes{\'u}s M. and Cervig{\'o}n, Carlos and Capiluppi, Andrea and Izquierdo-Cort{\'a}zar, Daniel}
}
@conference {Robles:2014:FSD:2597073.2597129,
	title = {FLOSS 2013: A Survey Dataset About Free Software Contributors: Challenges for Curating, Sharing, and Combining},
	booktitle = {Proceedings of the 11th Working Conference on Mining Software Repositories},
	series = {MSR 2014},
	year = {2014},
	pages = {396{\textendash}399},
	publisher = {ACM},
	organization = {ACM},
	address = {New York, NY, USA},
	abstract = {In this data paper we describe a data set obtained by means of performing an on-line survey to over 2,000 Free Libre Open Source Software (FLOSS) contributors. The survey includes questions related to personal characteristics (gender, age, civil status, nationality, etc.), education and level of English, professional status, dedication to FLOSS projects, reasons and motivations, involvement and goals. We describe as well the possibilities and challenges of using private information from the survey when linked with other, publicly available data sources. In this regard, an example of data sharing will be presented and legal, ethical and technical issues will be discussed.
},
	keywords = {anonymization, data combining, data sharing, ethics, free software, microdata, msr data showcase, open data, open source, privacy, Survey},
	isbn = {978-1-4503-2863-0},
	doi = {10.1145/2597073.2597129},
	url = {http://doi.acm.org/10.1145/2597073.2597129},
	attachments = {https://flosshub.org/sites/flosshub.org/files/msr14gregorio.pdf},
	author = {Gregorio Robles and Reina, Laura Arjona and Serebrenik, Alexander and Vasilescu, Bogdan and Gonz{\'a}lez-Barahona, Jes{\'u}s M.}
}
@article {1745,
	title = {SENTIMENT ANALYSIS OF FREE/OPEN SOURCE DEVELOPERS: PRELIMINARY FINDINGS FROM A CASE STUDY},
	journal = {Revista Eletr{\^o}nica de Sistemas de Informa{\c c}{\~a}o},
	volume = {13},
	year = {2014},
	month = {08/2014},
	abstract = {Software development is a human intensive activity. And as such, how developers face their tasks is of major importance. In an environment such as the one that is common in FOSS (free/open source software) projects where professionals (i.e., paid developers) share the development effort with volunteers, the morale of the development and user community is of major importance. In this paper, we present a preliminary analysis using sentiment analysis techniques to a FOSS project. We therefore mine the mailing list of a project and apply these techniques to the most relevant participants. Although the application is at this time limited, we hope that this experience can be of benefit in the future to determine situations that may affect the developers or the project, such as low productivity, developer abandonment, project forking, etc. },
	keywords = {developer productivity, FLOSS, mailing lists, natural language processing, openSUSE, sentiment analysis, software development; software repository mining},
	doi = {10.5329/RESI.2014.1302006},
	url = {http://189.16.45.2/ojs/index.php/reinfo/article/view/1677},
	attachments = {https://flosshub.org/sites/flosshub.org/files/1677-6732-1-PB.pdf},
	author = {Rousinopoulos, Athanasios-Ilias and Gregorio Robles and Gonz{\'a}lez-Barahona, Jes{\'u}s M.}
}
@proceedings {1439,
	title = {A Comprehensive Study of Software Forks: Dates, Reasons and Outcomes},
	volume = {378},
	year = {2012},
	pages = {1-14},
	publisher = {IFIP AICT},
	abstract = {Summary. In general it is assumed that a software product evolves within the authoring company or group of developers that develop the project. However, in some cases different groups of developers make the software evolve in different directions, a situation which is commonly known as a fork. In the case of free software, although forking is a practice that is considered as a last resort, it is inherent to the four freedoms. This paper tries to shed some light on the practice of forking. Therefore, we have identified significant forks, several hundreds in total, and have studied them in depth. Among the issues that have been analyzed for each fork is the date when the forking occurred, the reason of the fork, and the outcome of the fork, i.e., if the original or the forking project are still developed. Our investigation shows, among other results, that forks occur in every software domain, that they have become more frequent in recent years, and that very few forks merge with the original project.},
	keywords = {forking, forks, free software, Legal, open source, social, software evolution, sustainability},
	attachments = {https://flosshub.org/sites/flosshub.org/files/paper_0.pdf},
	author = {Gregorio Robles and Gonz{\'a}lez-Barahona, Jes{\'u}s M.}
}
@conference {1006,
	title = {Towards a Theoretical Model for Software Growth},
	booktitle = {Fourth International Workshop on Mining Software Repositories (MSR{\textquoteright}07:ICSE Workshops 2007)},
	year = {2007},
	pages = {21 - 21},
	publisher = {IEEE},
	organization = {IEEE},
	address = {Minneapolis, MN, USA},
	abstract = {Software growth (and more broadly, software evolution) is usually considered in terms of size or complexity of source code. However in different studies, usually different metrics are used, which make it difficult to compare approaches and results. In addition, not all metrics are equally easy to calculate for a given source code, which leads to the question of which one is the easiest to calculate without losing too much information. To address both issues, in this paper present a comprehensive study, based on the analysis of about 700,000 C source code files, calculating several size and complexity metrics for all of them. For this sample, we have found double Pareto statistical distributions for all metrics considered, and a high correlation between any two of them. This would imply that any model addressing software growth should produce this Pareto distributions, and that analysis based on any of the considered metrics should show a similar pattern, provided the sample of files considered is large enough.},
	keywords = {C, complexity, evolution, freebsd, growth, halstead, lines of code, loc, mccabe, metrics, scm, size, sloc, sloccount, source code},
	isbn = {0-7695-2950-X},
	doi = {10.1109/MSR.2007.31},
	attachments = {https://flosshub.org/sites/flosshub.org/files/28300021.pdf},
	author = {Herraiz, Israel and Jesus M. Gonzalez-Barahona and Gregorio Robles}
}
@conference {686,
	title = {Contributor Turnover in Libre Software Projects},
	booktitle = {OSS2006: Open Source Systems (IFIP 2.13)},
	series = {IFIP International Federation for Information Processing},
	year = {2006},
	pages = {273 - 286},
	publisher = {Springer},
	organization = {Springer},
	abstract = {A common problem that management faces in software companies is the high instability of their staff. In libre (free, open source) software projects, the permanence of developers is also an open issue, with the potential of causing problems amplified by the self-organizing nature that most of them exhibit. Hence, human resources in libre software projects are even more difficult to manage: developers are in most cases not bound by a contract and, in addition, there is not a real management structure concerned about this problem. This raises some interesting questions with respect to the composition of development teams in libre software projects, and how they evolve over time. There are projects lead by their original founders (some sort of {\textquotedblleft}code gods{\textquotedblright}), while others are driven by several different developer groups over time (i.e. the project {\textquotedblleft}regenerates{\textquotedblright} itself). 
In this paper, we propose a quantitative methodology, based on the analysis of the activity in the source code management repositories, to study how these processes (developers leaving, developers joining) affect libre software projects. The basis of it is the analysis of the composition of the core group, the group of developers most active in a project, for several time lapses. We will apply this methodology to several large, well-known libre software projects, and show how it can be used to characterize them. In addition, we will discuss the lessons that can be learned, and the validity of our proposal.
},
	keywords = {apache, committers, core, cvs, cvsanaly, developers, evolution, freebsd, gimp, gnome, kde, mono, mozilla},
	doi = {http://dx.doi.org/10.1007/0-387-34226-5_28},
	attachments = {https://flosshub.org/sites/flosshub.org/files/Contributor\%20Turnover\%20in\%20Libre\%20Software\%20Projects.pdf},
	author = {Gregorio Robles and Gonzalez-Barahona, Jesus}
}
@conference {Robles:2006:GLD:1137983.1138017,
	title = {Geographic location of developers at SourceForge},
	booktitle = {Proceedings of the 2006 international workshop on Mining software repositories},
	series = {MSR {\textquoteright}06},
	year = {2006},
	pages = {144{\textendash}150},
	publisher = {ACM},
	organization = {ACM},
	address = {New York, NY, USA},
	abstract = {The development of libre (free/open source) software is usually performed by geographically distributed teams. Participation in most cases is voluntary, sometimes sporadic, and often not framed by a pre-defined management structure. This means that anybody can contribute, and in principle no national origin has advantages over others, except for the differences in availability and quality of Internet connections and language. However, differences in participation across regions do exist, although there are little studies about them. In this paper we present some data which can be the basis for some of those studies. We have taken the database of users registered at SourceForge, the largest libre software development web-based platform, and have inferred their geographical locations. For this, we have applied several techniques and heuristics on the available data (mainly e-mail addresses and time zones), which are presented and discussed in detail. The results show a snapshot of the regional distribution of SourceForge users, which may be a good proxy of the actual distribution of libre software developers. In addition, the methodology may be of interest for similar studies in other domains, when the available data is similar (as is the case of mailing lists related to software projects).},
	keywords = {distributed, email, email address, free software, geographical location, geography, libre software, mining software repositories, open source software, sourceforge, timezone},
	isbn = {1-59593-397-2},
	doi = {http://doi.acm.org/10.1145/1137983.1138017},
	url = {http://doi.acm.org/10.1145/1137983.1138017},
	attachments = {https://flosshub.org/sites/flosshub.org/files/144GeographicLocation.pdf},
	author = {Gregorio Robles and Jesus M. Gonzalez-Barahona}
}
