Como el protagonista de π, uno tiene una cierta tendencia natural a buscar patrones en conjuntos de números. Bueno, lo suyo era obsesión y lo mío a veces raya en la fascinación. Como por ejemplo, mirando los números de AdSense. Y después de mirármelos un rato, mi primera (y segunda) respuesta a la pregunta del título es “como mínimo en obm, no demasiado”. (Y que conste que aunque no me sacarán de pobre, mis ingresos de Adsense son muy bienvenidos y, además, si Technorati no se equivocó mucho en su último estado de la blogosfera (ya comentado por aquí), estoy bastante por encima de la mediana de ingresos.)

Obsérvese, primero, la siguiente gráfica:

Medias móviles de impresiones de anuncios e ingresos en este blog, para un cierto periodo de seis meses

(Sí, la media móvil que cae en picado es la de impresiones, en consonancia con la deprimente pérdida de tráfico del blog. Y que cayeran visitas pero no ingresos es lo que me ha llevado a fijarme, efectivamente.)

No parece que haya mucha relación entre ambas categorías, ¿verdad? Pues si en vez de comparar ambas medias hacemos una gráfica de dispersión…

Dispersión de ingresos contra impresiones

Pues eso. Que si genero los puntos al azar igual me sale más aleatorio, pero no estoy yo muy seguro. Para los interesados, el coeficiente de correlación es de 0.18 y ni regresión lineal, ni exponencial, ni logarítmica, ni polinómica ni potencial ni puñetas, los coeficientes de determinación se arrastran…

Y me diréis… pero claro, hombre, las temáticas de los visitantes varían con el tiempo y el CPM hace lo propio. Y sí, yo también me lo he dicho. Y acto seguido he limitado el experimento a una única entrada (esa que representa como el 40% de las impresiones de anuncios del blog y el 35% de los ingresos y que, por tanto, a ojo de buen cubero he estimado significativa). Y… que si quieres arroz, Catalina…

Media móvil de impresiones contra ingresos de una única entrada

Y, por si quedaban dudas, la gráfica de dispersión:

Ingresos contra impresiones de una única entrada

La correlación, 0.21. Las diferentes regresiones, tan patéticas como antes.

En fin. Que ni recuerdo con mucha claridad la estadística de la carrera (aunque alguna cosa sí me quedó :-) ) ni soy un experto del tema pero, oiga, ¿no parece que Adsense juega a los dados con el CPM? Y cualquier aportación sobre el tema será muy bienvenida, desde luego.

• Habrá que seguir escribiendo… (2008.2.24) (1)
• YouTube Insight, métricas para tus vídeos (2008.3.27) (0)
• Y ahora, publicidad en los ‘feeds’ (2008.8.20) (2)
• Un millón doscientos mil álbumes, a ocho dólares el album… (2007.10.20) (1)
• Segundas impresiones de Google Chrome (2008.9.3) (4)

El debate de los candidatos a la vicepresidencia USA en el New York Times

Pues para que existan cosas tan brillantes como esta transcripción del debate de los candidatos a la vicepresidencia USA en el New York Times (me dice Isma que hace una semana ya hicieron lo mismo con el debate de los presidenciables y que servidor ni se había enterado, premio para mí).

Im presionante y digno de quitarse el sombrero. Brillante. Y, lo que es mejor, imposible fuera de la web.

• Warner se va de last.fm (2008.6.7) (0)
• Una pregunta (2008.7.14) (3)
• Un millón doscientos mil álbumes, a ocho dólares el album… (2007.10.20) (1)
• South Park, en la red (2008.3.24) (1)
• Sin DRM, tres de cuatro (2007.12.28) (0)

(Y programas un motor de física en WPF/Silverlight.) Esto:

Stimulant: Microsoft Surface + Nintendo Wii Mashup from Stimulant on Vimeo.

Es probable que no sirva para nada (nunca se sabe), pero mola… Origen, vía.

• Roland overdose (2008.4.1) (1)
• MTMini: un touchpad multitouch “hagalo usted mismo” (2008.5.20) (2)
• Microsoft TouchWall. Más multitouch de los laboratorios de Microsoft (2008.5.14) (1)
• Microsoft Popfly: ¿Microsoft y mash-ups? (2007.5.18) (1)
• Microsoft Popfly, en alfa (2007.5.29) (0)

Dominique has just announced that the odt2tbook plugin for OpenOffice.org has won an award. He does not mention he has been interviewed in a podcast about the OpenOffice.org community. Congratulations are in order!

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No me entiendan mal: sí, sabemos que los discos SSD llevan bastantes meses ya en el mercado. Pero hasta ahora un disco duro de 64 o 128 gigas con dicha tecnología suponía una inversión más que notable por megabyte, muy por encima de lo que cuestan las memorias Flash en formato tarjeta (el sábado me compraba yo 8 gigas en microSDHC por 30 euros, a menos de 4 euros el giga, mientras que los discos SSD están por encima de los 9, si miramos lo que cuesta cambiar el disco duro convencional de un portátil por un SSD)…

Pues parece que, finalmente, se acabó: como cuentan en Engadget (después de verlo en jkOnTheRun), un fabricante, SuperTalent anuncia (la cosa está enterrada entre sus notas de prensa, bastante poco enlazable) discos duros SSD SATA-II de 64 y 128 gigas de 2.5″ de 64 y 128 gigas con un “expected street price” de 179 y 299 dólares, respectivamente, con velocidades (máximas, ojo) de lectura y escritura de 100 y 40 megabytes por segundo. Colocando el precio del giga por debajo de los 2.50 dólares. Habrá que esperar a los primeros tests para comprobar las velocidades reales y los consumos de energía, pero el salto cualitativo, parece, ya está dado…

• No hay entradas relacionadas

Particularmente, me encanta el nuevo comportamiento de la nueva barra de direcciones de Firefox 3 (oficialmente, “awesome bar”). Pero un poco de “fine tuning” a veces no le vendría mal. Como apuntan en PC Magazine, no es difícil. Primero hay que ir a about:config, y después…

• Para volver a la ‘barra vulgaris’ de Firefox 2 ponemos browser.urlbar.maxRichResults a -1.
• Para limitar la búsqueda a aquellas URLs que hemos tecleado (olvidando, por tanto, aquellas a las que hemos navegado siguiendo un enlace), ponemos browser.urlbar.matchonlytyped a TRUE.
• Para evitar que busque en los bookmarks que no hemos visitado nunca, ponemos places.frecency.unvisitedBookmarkBonus a 0. Y si queremos quitar todos los bookmarks, también pondremos places.frecency.bookmarkVisitBonus a 0.

De nada…

• Tree Style Tab. Las pestañas de Firefox, en vertical (2008.8.27) (3)
• Mozilla y la interfaz del navegador en el móvil (2008.6.12) (1)
• Mozilla Prism, “site specific browsers” ad hoc (2008.3.11) (2)
• La beta de Firefox… (2007.11.21) (2)
• La aritmética de Firefox (2007.5.21) (2)

Septiembre es mes de cumpleaños y de mirar atrás. Aprovechando la casualidad de agenciarme el otro día una PC World de septiembre del 98 (sí, de hace diez años justos), os propongo una pequeña excursión por ‘Memory Lane’…

Bienvenidos a 1998. Crear un CD ROM es tema de portada. ¡Y se acerca Infovía 2!

¿Cuánto cuesta un ordenador? 245 000 pesetas (cerca de 1500 euros) compran un Pentium II con 64 megas de RAM, 4.3 gigas de disco, una tarjeta VGA con 8 megas y un monitor de 17. Im presionante...

¿Ha cambiado el mundo? ¿Recuerda alguien a Compaq?

Quizá no ha cambiado tanto. Salía un windows nuevo... y las revistas se planteaban si había que cambiar o quedarse con la versión anterior.

En la MacWorld Expo Steve Jobs presumía del tercer semestre consecutivo de resultados positivos, con un beneficio de 100 millones de dólares. Habían vendido tres cuartos de millón de Power Macs G3 en 9 meses, su web tenía diez millones de hits mensuales y se anunciaba Mac OS 8.5. El iPod aún ni se olía...

Maxtor anunciaba un disco de 3.4 gigas por plato... para un total de hasta 10 gigas. Inacabable...

En el entorno empresarial, Explorer estaba a punto de superar a Netscape Navigator...

Canon sacaba la Powershot A5. 1024 por 768. ISO 400 a baja resolución. 8 megas de almacenamiento. Y todo por... 150 000 pesetas. 900 euros. Un regalo, ¿eh?

Microsoft presentaba la beta 2 (sí, ya se estilaban las betas) de Office 2000. El periodista destacaba que ahora Office era capaz de escribir HTML. A cualquier cosa le llamaban HTML...

No tengo palabras. Un módem US Robotics de 56. Qué tiempos aquellos...

Se acercaba InfoVía Plus 2.0 y una 'guerra de redes IP'

Y se acercaba también Internet2, que había de ser mil veces más rápida que la existente. La conexión de RedIRIS a la red europea de alta velocidad era de 22 megabytes por segundo.

Como no se ve nada en la imagen, os tendréis que fiar de mi palabra: es una comparativa de portátiles 'baratos'... en que el más 'barato' está en 200 000 pesetas (1200 euros), que compraban un Toshiba Satellite 230 CX con un Pentium MMX a 133, 16 megas de RAM, pantalla de 12 pulgadas y 800 por 600, con 3 gigas de disco y 3 kilos de peso. Ya no se hacen ordenadores así...

¿Qué? ¿Vértigo? ;-)

• Y gira (2005.12.9) (5)
• The Star Wars hub (2008.6.27) (0)
• Roland overdose (2008.4.1) (1)
• Queridos Reyes Magos… (2008.1.5) (3)
• Pizarras digitales interactivas, el dossier completo (2008.5.13) (0)

Research by Andrea Kienle and Martin Wessner

I have been following the work by Kienle and Wessner during my analysis of related work in the area of scientific communities of practice. I want to point to the design patterns listed by the authors as I find them particularly interesting in the discussion on the future of the open knowledge society and its venues.

• Smooth transitions between different degrees of participation: New people with new ideas should be able to join the community as easily as possible; already existing members should be able to participate over a period of time on different levels.
• Networking of local coordinators: Local coordinators influence by their publications, lectures, and advice how other work is perceived by their fellows.
• Rotation of meeting locations: To provide low barriers for new people living near the meeting location to enter the community.
• International program committees: committee members distribute information about the conference locally and encourage people from their local networks to submit to the conference. International program committees may thus lead to more international group of authors.

These principles have been based on an empirical study and biometric analysis of the CSCL community as well as conceptual work by Etienne Wenger et Al.. The design principles have been applied to propose a community platform for the CSCL community. A community platform might also be potentially useful to foster the the exchange and discussion in the knowledge society.

For more detailed information see:

• Interdisciplinarity in the CSCL Community: An Empirical Study (2007)
• Analysing and cultivating scientific communities of practice (December 2006)
• The CSCL community in its first decade: development, continuity, connectivity (March 2006)
• Principles for Cultivating Scientific Communities of Practice (2005)

• Tagging is used to structure content (e.g. to generate personalized sequences of lecture material)
• Social tagging = collaborative structuring of content
• Tags attach specific information to an object
• Tags are usually keywords
• Tagging creates a common vocabulary, in social tagging this is also referred to as folksonomy
• My suggestions: Towards a more sophisticated (semantic) tagging: i.e. tags are semantic concepts, such as mathematical symbols (e.g. represented in OpenMath or (content) MathML) with commonly agreed on or private definitions, which are stored in Content Dictionaries
• But: Maybe this conflicts with the definitions in the inclusive tagging paper (WSKS) as the authors distinguish between different levels of annotation (from tag to formal metadata). But considering the very general definition of “tagging is attaching specific information to an object”; we might want to include semantics concepts as potential tag-categories.
• We provide a corpus of semantically marked up documents in the OMDoc format and respective workflows which allow the automatic extraction of mathematical symbols (which we want to use as semantic tags). For example, the panta rhei system provides an import for OMDoc during which it extracts all symbols; we simply need to memorizes the relation of symbols and the imported content snippets to provide the respective tags.
• Moreover, I suggest to distinguish two types of semantic tags: acquired symbols and required symbols (prerequisites). Based on our OMDoc markup we can identify which symbols are required for the illustration in a mathematical theory and which symbols are acquired when studying the theory: Required symbols are specified via the OMDoc import-elements (which imports symbols from another mathematical theory) and acquired symbols, which are simply all remaining symbols that are not imported from other mathematical theories. Acquired symbols are defined/ introduced in the given theory.
• Based on the extracted tag, we can visualize tag clouds for each content (e.g. in panta rhei)
• We should also provide a user interface for creating tags:
  • Users can associate symbols to content snippets in the system (in particular to non-semantic content such as the forum, the library entries, manually entered problems — this allows us to use the semantic objects to bring order/structure in the collection of non-semantic content);
  • Users can create new tags (new symbols); this interface needs to be very intuitive, easy, and usable.
  • Maybe we can also allow users to use keywords for tagging: But these are non-semantic tags and should be disntiguished
• Based on tagging-structure we can implement tag-based browsing: Given a tag cloud; the selection of a tag provides (i) all resources tag with this tag and (ii) all users that used this tag; clicking on a resources provides the collection of all tags of this resources and the collection of all users that tag this resource; selecting a user provides all his tags and tagged resources …
• However: the tagging of non-semantic content restricts the granularity of the tags (as we cannot annotate fine granular content inside e.g. a post, we do not have IDs; maybe we have to consider a different annotation approach - e.g. based on xpointer as annotae is doing it); However, for now we neglect the granularity. If a posting annotates a content, we extract the symbols of the annotated area and use them to automatically tag the posting; if the posting links to other content we propagate the tags to this content

Further Readings

• How do others define/ interpret semantic tags? e.g. see [1]; [2]; [3] (German)

Presentation by Mladjan Jovanovic at the 1st World Summit of the Open Knowledge Society, Athens, 24-26 September 2008. Track: Knowledge, Learning, Education, Learning Technologies, and eLearning for the Knowledge Society.

Unfortunately I missed this talk as it was in parrallel to my session. The authors present a framework that based on user profiles generates user-adaptive educational games. They base their user profile on psychological studies of motivation and social behaviour (see below) and apply the Self-Determination Theory, which provides the following classification of motivation:

• Intrinsic: motivtion is not based on any external benefits, inherint satisfaction
• Extrinsic: performance for outcome (money, rewards)
• Amotivation: absence of motivation

I would be glad to read further papers on their work and to see an example of various games for the different user profiles they identify and construct.

Further Reading:

• Introduction to multimodal interaction
• Federation of American Scientists: R&D Challenges in Games for Learning
• Brasford, Brows, Cocking: How people learn: brain, mind, experience, and school.
• R.M Ryan: Self-Determination theory and the facilitation of intrinsic motivation, social development, and well-being.

Presentation by Katarzyna Musial at the 1st World Summit of the Open Knowledge Society, Athens, 24-26 September 2008. Track: Social & Humanistic Computing for the Knowledge Society: Emerging Technologies and Systems for the Society and Humanity.

Presentation by Vincenza Carchiolo at the 1st World Summit of the Open Knowledge Society, Athens, 24-26 September 2008. Track: Knowledge, Learning, Education, Learning Technologies, and eLearning for the Knowledge Society.

One of the major advantages of E-learning is the personalization of learning paths. But currently lifelong learning scenario often consists of a P2P network of prosumers (provider+consumers), so no central authority manages the learning objects. Thus the choice of the best learning materials as well as the best order (learning paths) is problematic.

The authors distinguish two types of trust: Trust among peers, which allows to express which one is more reliable (authoritative) in answering a query within a given topic (described by shared ontology). Trust peer-learn objects express which LOs are considered more useful by that peer.

Approach: The proposed model is based on a peer-to-peer network with prosumers and LOs (modelled as a directed multigraph). A peers stores his suggested learning paths LOS precedences-successions and relations) and assigns trust to peers and resources. LO is a resource described through its set of prerequisites and objectives. Peer-to-peer trust expresses the reliability a peer assigns to another peer about a given topic, the label is trustworthiness in the [-1;1] range. Peer-to-resource trust expresses the reliability a peer assigns to a resource. Learners can assign a query to search for reliable and personalized learning paths by providing: prerequisites and objectives; total time available; level of difficulty; and a threshold for trustworthiness. The results is a sequence of resources.

Related work: Ariadne, ALFAnet, Edutella.

This works is currently focusing on global learning scenarios without authority, not university scenarios. But it could be applied to an university-scenarios. Just that we would have to change the traditional way, in which students are consumers only. They should of course trust the lecturer, but should be encourage to contribute to the course, to enrich the course content with pointers to the web, new problems, and examples. Then trusting peers could help students to improve their lecture materials.

The JEM server was down most of today, Saturday, September 27. The JEM server is located in a machine room of the Physics Department, and, of course, none of the administrators of the machine room was reachable off hours. Together with Antti Alamäki I then went to Campus, got the security guard to let us in to the machine room, and rebooted ubu, the JEM server.

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Presentation by Przemyslaw Kazienko at the 1st World Summit of the Open Knowledge Society, Athens, 24-26 September 2008. Track: Social & Humanistic Computing for the Knowledge Society: Emerging Technologies and Systems for the Society and Humanity.

Two users participate in common activity related to the certain object with the same/ different role a: e.g. two users comment on the same image. The weights of relations depend on intensity, frequency and quantity. Distinction of different layers of the social network: contact lists, tags, groups, favourites, opinions, multi relational social network. Some layers have rather social (contacts, opinion-author, author-opinion); others have more semantic relations (tags, opinion-opinion relation).

The goal of the system is to recommend people to people. First relations are extracted - building the different layers of the social network (distinction between direct relations (contacts) and object-based relations (tags, opinions, favourites, groups). Based on the layers we create weights for the importance of each layer (consisting personal weight = the user’s individual weight of the user for each layer; and a system weight = aggregation over all users). Afterwards, a social filtering is applied: that is rejection based on the user’s contact lists; rejection of users blocked by the user, damp already viewed users. Rotation mechanism for more random results. Finally, the recommendation is presented to the user. Users are then asked to rate the recommendations.

Presentation by Michal Zemlicka (Charles University Prague; Faculty of Mathematics and Physics; Department of Software Engineering) at the 1st World Summit of the Open Knowledge Society, Athens, 24-26 September 2008. Track: Social & Humanistic Computing for the Knowledge Society: Emerging Technologies and Systems for the Society and Humanity.

Problem: STEM disciplines are very unpopular. Scientists and engineers are usually presented as crazy. Learning STEM is quite hard and requires hard work (and some minimal talent). STEM are taught less than before. Educated and well prepared teachers are required and they are expensive. Labs are expensive. People able to teach STEM can succeed also in other profession (we are lacking STEM specialists).

Approach to change the public opinion: The authors propose to create a system showing how successful alumnies of different school have become. They want to show that the knowledge of mathematicians is an advantage for being employed and having big income (tax statements).

Limits: All technical issues seem to have solved (architecture, certification, encryption, privacy). The main problem is that the use of the existing data is prohibited by law. There will be a powerful lobby of poor schools against such a system.

The authors want to prove the quality of an educational system by using the average success of alumnies. In the discussion it was criticized that “employment” is a rather poor parameter for a complex system such as education and that a more sophisticated approach needs to be taken.

Presentation by Pui-Yee Chiu at the 1st World Summit of the Open Knowledge Society, Athens, 24-26 September 2008. Track: Social & Humanistic Computing for the Knowledge Society: Emerging Technologies and Systems for the Society and Humanity.

see also Do we know how to use facebook?

Our paper on “CoPit - the community of practice toolkit based on semantically marked up artifacts” received one of the best paper awards at the 1st World Summit of the Open Knowledge Society, Athens, 24-26 September 2008: The paper scored 2nd in the track “Social & Humanistic Computing for the Knowledge Society: Emerging Technologies and Systems for the Society and Humanity”.

At the beginning I was confused that there were several best paper awards for each conference track (altogether 10?). But having a broader recognition of contribution, actually allows a much better overview on the conference’s focus and expectations. Below I am listing the best papers of WSKS 2008 (list is not yet complete).

Track: Social & Humanistic Computing for the Knowledge Society: Emerging Technologies and Systems for the Society and Humanity

1. Inclusive Social Tagging
2. CoPit - the community of practice toolkit based on semantically marked up artifacts

Track: Knowledge, Learning, Education, Learning Technologies, and eLearning for the Knowledge Society.

1. Educational Games Design Issues: Motivation and Multimodal Interaction

Proposed Projects:

• Open Research Society (ORS) Journal Collections: new members become associate editors of open journals
• ORS Book Collections
• ORS Learning Resource Collection: Encouraging initiatives for open educational repositories; but provide quality control; e.g. created an ORS lens in Connexions; new members can become members of the assessment board for open learning materials
• ORS University: vision of an open university with open courses

Organization of ORS via open policies, which are documents that contain procedures or principles for the different areas of actions of the ORS. See further information on ors.org (see also their wiki)

See paper “Open research - the ORS way” for the vision of the Open Knowledge Society.