Scale and Translation Invariant Collaborative Filtering Systems   总被引：1，自引：0，他引：1  

Daniel Lemire 《Information Retrieval》2005,8(1):129-150

Collaborative filtering systems are prediction algorithms over sparse data sets of user preferences. We modify a wide range of state-of-the-art collaborative filtering systems to make them scale and translation invariant and generally improve their accuracy without increasing their computational cost. Using the EachMovie and the Jester data sets, we show that learning-free constant time scale and translation invariant schemes outperforms other learning-free constant time schemes by at least 3% and perform as well as expensive memory-based schemes (within 4%). Over the Jester data set, we show that a scale and translation invariant Eigentaste algorithm outperforms Eigentaste 2.0 by 20%. These results suggest that scale and translation invariance is a desirable property.  相似文献   

An Investigation of Textbook Vetting and Evaluation Process in Tanzania     

Daniel C. Rotich  Emily J. Kogos  Zamda R. Geuza 《Publishing Research Quarterly》2018,34(1):96-109

Textbook vetting and evaluation process intends to ensure that the materials provided are relevant, of the required quality, suitable ad would enhance learning efficiency and effectiveness. The paper investigates the role of publishers and Tanzania Institute of Education (TIE) in the textbooks vetting and evaluation process; examines factors used to vet, evaluate and approve primary and secondary school textbooks in Tanzania and proposes Strategies that would enhance the textbook vetting, evaluation and process. The study used a mixed method research design. Respondents were selected educational publishers; MoEVT, Baraza la Kiswahili Tanzania, TIE, and Publishers Association of Tanzania. Questionnaire and semi- structured interview were used to collect data which were analysed qualitatively and quantitatively. Major findings of the study were; textbooks vetting and evaluation process is not professionally conducted although standard criteria have been established; there is not well established roles among key players involved in the vetting and evaluation process leading to conflict of interest between TIE and the publishers. The study recommends establishing an independent professional evaluation board and a well-defined timetable and effective communication among various players; enacting a book policy and adopting a limited multiple-textbook publishing system.  相似文献   

Editorial     

Daniel M. Pennell 《Slavic & East European Information Resources》2018,19(1-2):1-2

  相似文献   

Applying LDA Topic Modeling in Communication Research: Toward a Valid and Reliable Methodology     

Daniel Maier  A. Waldherr  P. Miltner  G. Wiedemann  A. Niekler  A. Keinert 《Communication methods and measures》2018,12(2-3):93-118

ABSTRACT

Latent Dirichlet allocation (LDA) topic models are increasingly being used in communication research. Yet, questions regarding reliability and validity of the approach have received little attention thus far. In applying LDA to textual data, researchers need to tackle at least four major challenges that affect these criteria: (a) appropriate pre-processing of the text collection; (b) adequate selection of model parameters, including the number of topics to be generated; (c) evaluation of the model’s reliability; and (d) the process of validly interpreting the resulting topics. We review the research literature dealing with these questions and propose a methodology that approaches these challenges. Our overall goal is to make LDA topic modeling more accessible to communication researchers and to ensure compliance with disciplinary standards. Consequently, we develop a brief hands-on user guide for applying LDA topic modeling. We demonstrate the value of our approach with empirical data from an ongoing research project.  相似文献   

<Emphasis Type="Bold">Heidegger’s Wrong Turn</Emphasis>     

Daniel Bonevac 《Academic Questions》2017,30(3):302-320

  相似文献   

Masked by Trust: Bias in Library Discovery     

Ellen K. Wilson 《Public Services Quarterly》2020,16(1):32-33

  相似文献   

Academe’s House Divided     

Daniel B. Klein 《Academic Questions》2011,24(3):365-370

  相似文献   

Decoding general relativity     

Daniel Kennefick 《Metascience》2011,20(1):91-93

  相似文献   

Degree Completers at Baccalaureate Arts and Sciences Institutions and the Contemporary U.S. Macroeconomy     

Rachel Wilson  Brian Yontz 《Innovative Higher Education》2015,40(1):51-61

  相似文献   

One step antibody-mediated isolation and patterning of multiple cell types in microfluidic devices     

Danny Bavli  Elishai Ezra  Daniel Kitsberg  Margarita Vosk-Artzi  Shashi K. Murthy  Yaakov Nahmias 《Biomicrofluidics》2016,10(2)

Cell-cell interactions play a key role in regeneration, differentiation, and basic tissue function taking place under physiological shear forces. However, current solutions to mimic such interactions by micro-patterning cells within microfluidic devices have low resolution, high fabrication complexity, and are limited to one or two cell types. Here, we present a microfluidic platform capable of laminar patterning of any biotin-labeled peptide using streptavidin-based surface chemistry. The design permits the generation of arbitrary cell patterns from heterogeneous mixtures in microfluidic devices. We demonstrate the robust co-patterning of α-CD24, α-ASGPR-1, and α-Tie2 antibodies for rapid isolation and co-patterning of mixtures of hepatocytes and endothelial cells. In addition to one-step isolation and patterning, our design permits step-wise patterning of multiple cell types and empty spaces to create complex cellular geometries in vitro. In conclusion, we developed a microfluidic device that permits the generation of perfusable tissue-like patterns in microfluidic devices by directly injecting complex cell mixtures such as differentiated stem cells or tissue digests with minimal sample preparation.  相似文献