Taking advantage of unexpected WebCONSORT results

To estimate treatment effects, trials are initiated by randomising patients to the interventions under study and finish by comparing patient evolution. In order to improve the trial report, the CONSORT statement provides authors and peer reviewers with a guide of the essential items that would allow research replication. Additionally, WebCONSORT aims to facilitate author reporting by providing the items from the different CONSORT extensions that are relevant to the trial being reported. WebCONSORT has been estimated to improve the proportion of reported items by 0.04 (95% CI, –0.02 to 0.10), interpreted as “no important difference”, in accordance with the scheduled desired scenario of a 0.15 effect size improvement. However, in a non-scheduled analysis, it was found that, despite clear instructions, around a third of manuscripts selected for trials by the editorial staff were not actually randomised trials. We argue that surprises benefit science, and that further research should be conducted in order to improve the performance of editorial staff.Peer ReviewedPostprint (published version

A linear optimization based method for data privacy in statistical tabular data

National Statistical Agencies routinely disseminate large amounts of data. Prior to dissemination these data have to be protected to avoid releasing confidential information. Controlled tabular adjustment (CTA) is one of the available methods for this purpose. CTA formulates an optimization problem that looks for the safe table which is closest to the original one. The standard CTA approach results in a mixed integer linear optimization (MILO) problem, which is very challenging for current technology. In this work we present a much less costly variant of CTA that formulates a multiobjective linear optimization (LO) problem, where binary variables are pre-fixed, and the resulting continuous problem is solved by lexicographic optimization. Extensive computational results are reported using both commercial (CPLEX and XPRESS) and open source (Clp) solvers, with either simplex or interior-point methods, on a set of real instances. Most instances were successfully solved with the LO-CTA variant in less than one hour, while many of them are computationally very expensive with the MILO-CTA formulation. The interior-point method outperformed simplex in this particular application.Peer ReviewedPreprin

Problemas numéricos con corrección automática: qué se puede y qué se debe hacer

La presente comunicación describe los objetivos, organización, proceso y divulgación de un taller orientado a proporcionar a docentes del campo de la estadística y la investigación operativa (y posiblemente de otros campos) una primera noción sobre la construcción de problemas con la plataforma e-status. El taller se estructura en base a cuatro casos que van incrementando el nivel de complejidad, para ir mostrando diversas posibilidades didácticas a la hora de elaborar buenos ejercicios que hagan reflexionar al estudiante.Peer ReviewedPostprint (published version

Use and interpretation of confidence intervals

Interprete los intervalos de confianza como informativos de1: los valores poblacionales compatibles con los resultados observados; y2 la magnitud de la incertidumbre restante tras el estudio. Y si no existe un proceso de azar en la generación de los datos, o si el estudio tiene alguna impureza, admita cautamente las limitaciones presentes en el estudio y recuerde que la incertidumbre sería mayor que la reflejada por el intervalo.Peer ReviewedPostprint (published version

The P value is out of date

En esta píldora seguimos las guías de publicación1 y la declaración de la American Statistical Association (ASA)2. Pretendemos convencerle de que no use el valor de P (o P-value). No es tarea fácil. Pero seamos sinceros: tampoco habíamos entendido bien por qué el valor de P era tan importante. Esta discusión dura ya casi 100 años. Proponemos no resistirnos más al cambio. Puede ser un buen momento para reflejar la incertidumbre de otra manera.Peer ReviewedPostprint (published version

The objective guides design and analysis

Peer ReviewedPostprint (published version

A fast CTA method without the complicating binary decisions

Peer ReviewedPostprint (published version

E-status: a web tool for learning by doing exercises

The paper introduces the project led by a team of teachers to assist students learn statistics. The goal is to build a tool able to present mathematical problems and to correct the students´ answers. The problems may include random data, so the solution cannot be previously known (if solved before) and the student can reconsider it if necessary. Pedagogical implications are commented, since the method can be effective on the basic and middle domains of learning, as well as on higher levels, specially if careful design of the problems is applied.Postprint (published version

Estadística y salud : principios metodológicos en las guías de publicación

Descripció del recurs: 6 octubre 2023Este texto introduce los retos principales que afronta la Bioestadística en salud. Puede que el más grande de ellos sea conseguir una notación compartida por teóricos y aplicados. En consecuencia, pretende explicar conceptos básicos a toda la comunidad académica, tanto la aplicada (medicina, enfermería, farmacia, odontología, etc.) como la teórica (estadística, matemática, informática, ingeniera, etc.). Aborda únicamente conceptos que disponen de consenso científico, encontrados en las guías de publicación impulsadas por la red EQUATOR.

Assessing Shiny apps through student feedback: recommendations from a qualitative study

This is the accepted version of the following article: Gonzalez, J., Lopez, M., Cobo, E., Cortes, J. Assessing Shiny apps through student feedback: recommendations from a qualitative study. "Computer applications in engineering education", Setembre 2018, vol. 26, núm. 5, p. 1813-1824., which has been published in final form at https://onlinelibrary.wiley.com/doi/abs/10.1002/cae.21932Teaching statistics has benefited from Java applets, the successful technology that appeared in the late 90s and which allowed real interactivity on an Internet browser. Combining dynamic functionality with the web provides an inspirational complement to the contents of many subjects in undergraduate statistics courses, especially for active learning activities. Since Java applets are becoming obsolete, we explore a different technology based on R (currently a popular statistical language) and Shiny, which is a web framework for developing interactive applications inside the R environment. Although the pedagogical value of these tools has been implicitly accepted so far, our aim is to consider the students' perspective while investigating more suitable means to accompany the use of apps in statistics. We conducted a qualitative study in which we tested 10 of our applications and collected student opinions through questionnaires and regular meetings. Our conclusions indicate that the students view these resources positively, although they demand more support, just enough to facilitate both getting started and using the tools effectively. In addition, programming in R is surely more accessible and satisfying for statistics lecturers than other languages and, consequently, implementing instructional activities can be specially tailored by the teacher.Peer ReviewedPostprint (author's final draft