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The field of personalized product recommendation systems has seen tremendous growth in recent years. The usefulness of the algorithms’ abilities to filter out data from vast sets has been shown to be crucial in today’s information-heavy online experience. Our goal is therefore to compare two recommender models, one based on Random Indexing, the other on Collaborative Filtering, in order to find out if one is better suited to the task than the other. We bring up relevant previous research to set the context for our study, its limitations and possibilities. We then explain the theories, models and algorithms underlying our two recommender systems and finally we evaluate them, partly through empirical data collection from our employer Kavall’s platform, and partly through analysing data from interviews. We judge that our study is scientifically relevant as it compares an algorithm that is rarely used in this context, Random Indexing, to a more established recommendation algorithm, Collaborative Filtering, and as such the result of this comparison might give useful insights into the further development of new or existing algorithms. While more testing is required, the study did show signs that Random Indexing does have the potential of outperforming Collaborative Filtering in some areas, and further development of the model might be a worthwhile endeavor. Området för personliga produktrekommendationer har sett en enorm tillväxt under de senaste Åren. Användbarheten av algoritmernas förmåga att filtrera ut data ur stora uppsättningar har visat sig vara avgörande i dagens informationstunga onlineupplevelse. Vårt mål Är därför att jämföra två rekommendatormodeller, en baserad på Random Indexing, den andra på Collaborative Filtering, för att ta reda på om den ena Är bättre lämpad för uppgiften Än den andra. Vi tar upp relevant tidigare forskning för att sätta sammanhanget för vår studie, dess begränsningar och möjligheter. Vi förklarar sedan de teorier, modeller och algoritmer som ligger till grund för våra två rekommendationssystem och slutligen utvärderar vi dem, dels genom empirisk datainsamling från vår arbetsgivare Kavalls plattform, dels genom att analysera data från intervjuer. Vi bedömer att vår studie Är vetenskapligt relevant då den jämför en algoritm som sällan används i detta sammanhang, Random Indexing, med en mer etablerad rekommendationsalgoritm, Collaborative Filtering, och som sådan kan resultatet av denna jämförelse ge användbara insikter i den fortsatta utvecklingen av nya eller befintliga algoritmer. även om fler tester krävs, visade studien tecken på att Random Indexing har potentialen att överträffa Collaborative Filtering på vissa områden, och vidareutveckling av modellen kan vara ett givande åtagande.

Este artículo contiene 9 páginas, 4 figuras, 2 tablas., Wildfire magnitude and frequency have greatly escalated on a global scale. Wildfire products rich in biogenic elements can enter the ocean through atmospheric and river inputs, but their contribution to marine phytoplankton production is poorly understood. Here, using geochemical paleo-reconstructions, a century-long relationship between wildfire magnitude and marine phytoplankton production is established in a fire-prone region of Kimberley coast, Australia. A positive correlation is identified between wildfire and phytoplankton production on a decadal scale. The importance of wildfire on marine phytoplankton production is statistically higher than that of tropical cyclones and rainfall, when strong El Niño Southern Oscillation coincides with the positive phase of Indian Ocean Dipole. Interdecadal chlorophyll-a variation along the Kimberley coast validates the spatial connection of this phenomenon. Findings from this study suggest that the role of additional nutrients from wildfires has to be considered when projecting impacts of global warming on marine phytoplankton production., This work was supported by the National Natural Science Foundation of China (42030402, 41876127) and the Western Australian Marine Sciences Institution. O.S. was supported by I + D + i projects RYC2019-027073-I and PIE HOLOCENO 20213AT014 funded by MCIN/AEI/10.13039/501100011033 and FEDER. Funding was provided to P.M. through an Australian Research Council LIEF Project (LE170100219). This work is contributing to the ICTA “Unit of Excellence” (MinECo, MDM2015-0552).

Julie N. Books: What is Film?Frankfurt: Peter Lang 2016 (American University Studies – Series V: Philosophy, Bd.224), 160 S., ISBN 9781433134081, EUR 59,95Jihoon Kim: Between Film, Video, and the Digital: Hybrid Moving Images in the Post-Media Age London: Bloomsbury Academic 2016 (International Texts in Critical Media Aesthetics, Bd.10), 381 S., ISBN 9781628922936, GBP 79,99

Michael R. Müller, Jürgen Raab, Hans-Georg Soeffner (Hg.): Grenzen der Bildinterpretation; Philipp Stoellger, Marco Gutjahr (Hg.): Visuelles Wissen: Ikonische Prägnanz und Deutungsmacht; Wolfgang Wildgen: Visuelle Semiotik: Die Entfaltung des Sichtbaren vom Höhlenbild bis zur modernen Stadt

According to art historian James Elkins, the very term of ›visual literacy‹ is to be assessed as an at least »slightly dubious expression« (ELKINS 2008: 8) if not, in its linking of the scriptural to the pictorial or the discoursive to the non-discoursive, as an outright »self-defeating paradox« (ELKINS 2008: 5). In much of the same sense, William Mitchell views this arguably problematic though historically quite successful term as »a strong and seemingly unavoidable metaphor« (MITCHELL 2008a: 11) in which, though not mutually exclusive, the term of ›reading‹ serving as the vehicle and the term of ›vision‹ as the tenor thus are establishing a kind of hierarchy by apparently privileging the former over the latter in a kind of catachresis (in which the metaphor fills the gap of the lack of a literal or ›proper‹ designation)—literacy explains visuality just as texts explain pictures. At the same time, however, this relation might as well be reversed (so that Mitchell in fact wonders if one should speak of ›visual literacy‹ or ›literary visualcy‹): even verbal literacy does in fact rely on vision as, most evidently, for example, »the skill of reading is already a visual skill« (MITCHELL 2008a: 11), just as even face-to-face communication is governed by the recognition of facial expression, gestures, posture etc. (or ›body lan-guage‹, to use another metaphor of that kind). Neither, then, is literacy ever thoroughly independent of vision (or, more generally, communication of per-ception) nor is vision itself ever ›purely optical‹ regarding its physiological predispositions—let alone a ›natural‹ capacity exempt from learning and training (cf. MITCHELL 2008b: 13, 15). The same metaphorical, paradoxical, or oxymoronic combination of this seeming contradictio in adjecto, I would like to argue, can be found in the concept of an écriture filmique, or ›filmic writing‹, which in the following I will discuss with special regard to recent changes in the wider scope of today’s media culture: just as film, according to intermediality scholar Joachim Paech, has ultimately become a mere metaphor for virtually »every kind of moving picture« (PAECH 2011: 8), writing correspondingly may as yet be noth-ing more than a metaphor for its own remediation in a postmedial era (cf. BOLTER/GRUSIN 2000; WEIBEL 2005), along with ›literacy‹ as a metaphor or syn-ecdoche for several kinds of ›new literacies‹ (cf. BUCKINGHAM 1993; LANK-SHEAR/KNOBEL 2006; LEU/KINZER/COIRO/CAMMACK 2004)—›computer‹,› digital‹, ›information‹, ›media literacy‹ etc. as certain particularly mediatized ›cultural techniques‹ considered elementary for current quotidian communicative competence—in short, to quote Colin Lankshear and Michele Knobel, the general and extensive »semiotic competence« necessary to cope with today’s multimodal »post-typographic texts and technologies« (LANKSHEAR/KNOBEL 2006: 3, 5). The comparative linking of both concepts characterized in this way, then, hopefully still will not result in an explanation metaphoram per meta-phoram, that is, rather tautologically, idem per idem, or even obscurum per obscurius and ignotum per ignotius, but rather aims to contrast two particular reflections on visual literacy by their respective depictions of the lack of it; one philosophical-textual as a general diagnosis of today’s media culture and one artistic-filmic as a specific case in point. In a very cursory way, then, I will discuss: firstly Vilém Flusser’s concept of the ›techno-image‹ as the latest and, implicitly, also the last ›symbolic form‹ of cultural history, and: secondly a film by Peter Greenaway centrally addressing the problem of the ›reading‹ of an image—The Draughtsman’s Contract (1982)—in order to: thirdly and conclusively address the concept of an écriture filmique as founded in Alexandre Astruc’s seminal essay The Birth of a New Avantgarde and its possible uses for the situation of today’s media culture.

Jörg Helbig, Arno Russegger, Rainer Winter (Hg.): Visuelle Medien; Jörg Helbig, Arno Russegger, Rainer Winter (Hg.): Visualität, Kultur und Gesellschaft; Alice Pechriggl, Anna Schober (Hg.): Hegemonie und die Kraft der Bilder

Hans-Edwin Friedrich, Hans J. Wulff (Hg.): Scripturacinematographica: Texttheorie der Schrift in audiovisuellen Medien; Florian Krautkrämer: Schrift im Film

We describe a construction for d-polytopes generalising the well known stacking operation. The construction is applied to produce 2-simplicial and 2-simple 4-polytopes with g_2=0 on any number of n >= 13 vertices. In particular, this implies that the ray l_1, described by Bayer (1987), is fully contained in the convex hull of all flag vectors of 4-polytopes. Especially interesting examples on 9, 10 and 11 vertices are presented., 20 pages, 18 figures; minor corrections and changes in notation, added reference

Nadja Elia-Borer, Constanze Schellow, Nina Schimmel, Bettina Wodianka (Hg.): Heterotopien. Perspektiven der intermedialen Ästhetik; Mario Doulis, Peter Ott (Hg.): Remediate. An den Rändern von Film, Netz und Archiv/At the Borders of Film, Internet and Archives

Michael Hanke, Steffi Winkler (Hg.): Vom Begriff zum Bild. Medienkultur nach Vilém Flusser; Friedrich Balke, Bernhard Siegert, Joseph Vogl (Hg.): Mediengeschichte nach Friedrich Kittler