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1.
Robert W. P. Luk 《Information Retrieval》2008,11(6):539-561
This paper discusses various issues about the rank equivalence of Lafferty and Zhai between the log-odds ratio and the query
likelihood of probabilistic retrieval models. It highlights that Robertson’s concerns about this equivalence may arise when
multiple probability distributions are assumed to be uniformly distributed, after assuming that the marginal probability logically
follows from Kolmogorov’s probability axioms. It also clarifies that there are two types of rank equivalence relations between
probabilistic models, namely strict and weak rank equivalence. This paper focuses on the strict rank equivalence which requires
the event spaces of the participating probabilistic models to be identical. It is possible that two probabilistic models are
strict rank equivalent when they use different probability estimation methods. This paper shows that the query likelihood,
p(q|d, r), is strict rank equivalent to p(q|d) of the language model of Ponte and Croft by applying assumptions 1 and 2 of Lafferty and Zhai. In addition, some statistical
component language model may be strict rank equivalent to the log-odds ratio, and that some statistical component model using
the log-odds ratio may be strict rank equivalent to the query likelihood. Finally, we suggest adding a random variable for
the user information need to the probabilistic retrieval models for clarification when these models deal with multiple requests. 相似文献
2.
In this introductory article, we discuss the nature of Program Evaluation, describing the concepts that underlie our formal
and informal evaluative efforts. Program Evaluation, like any deliberate inquiry process, is about learning. The process explicates
program purposes, activities, and outcomes and generates knowledge about their merit and worth. This knowledge can inform
planning and lead to program improvement. We present and discuss various definitions of Program Evaluation, focussing on its
purposes and uses. We also provide an overview of the inquiry process, grounding the search for merit and worth in the American
Evaluation Association's Guiding Principles for Evaluators. Because program evaluations are typically conducted to inform
decision makers, we discuss aspects of professional practise that contribute to the use of an evaluation.
This chapter draws heavily on previous work by Sharon Rallis and Gretchen Rossman; see the following references. Rallis, S.F.
and Rossman, G.B., “Mixed Methods in Evaluation Contexts: A Pragmatic framework”, in A. Tashakkori and C. Teddlie (eds.),Handbook of Mixed Methods in the Social and Behavioral Sciences (Thousand Oaks: Sage, 2002). Rallis, S.F. and Rossman, G.B., “Communicating Quality and Qualities: The Role of the Evaluator
as Critical Friend”, in A.P. Benson, D.M. Hinn and C. Lloyd (eds.),Visions of Quality: How Evaluators Define, Understand, and Represent Program Quality (Oxford: JAI Press, 2001), pp. 107–120. Rallis, S.F. and Rossman, G.B. “Dialogue for Learning: Evaluator as Critical Friend”,
in R. Hopson and M.Q. Patton (eds.),How and Why Language Matters in Evaluation, New Directions for Evaluation, 86 (San Francisco: Jossey-Bass, 2000). Rossman, G.B. and Rallis, S.F.,Learning in the Field: An Introduction to Qualitive Research, 2nd edition (Thousand Oaks: Sage, 2003). Rossman, G.B. and Rallis, S.F., “Evaluation as Learning: Critical Inquiry and Use
as Action”, in V.J. Caracelli and H. Preskill (eds.),The Expanding Scope of Evaluation Use, New Directions in Evaluation 88 (San Francisco: Jossey Bass, 2000). 相似文献
3.
Much work on automated information filtering has been done in the TREC and TDT domains, but differences in corpora, the nature of TREC topics vs. TDT events, the constraints imposed on training and testing, and the choices of performance measures confound any meaningful comparison between these domains. We attempt to bridge the gap between them by evaluating the performance of the k-nearest-neighbor (kNN) classification system on the corpus and categories from one domain using the constraints of the other. To maximize comparability and understand the effect of the evaluation metrics specific to each domain, we optimize the performance of kNN separately for the F
1, T9P (preferred metric for TREC-9) and C
trk (official metric for TDT-3) metrics. Through a thorough comparison of our within-domain and cross-domain results, our results demonstrate that the corpus used for TREC-9 is more challenging for an information filtering system than the TDT-3 corpus and strongly suggest that the TDT-3 event tracking task itself is more difficult than the TREC batch filtering task. We also show that optimizing performance in TREC-9 and TDT-3 tends to result in systems with different performance characteristics, confounding any meaningful comparison between the two domains, and that T9P and C
trk both have properties that make them undesirable as general information filtering metrics. 相似文献
4.
Seon-Kyoung An Llewyn Elise Paine Jamie Nichole McNiel Amy Rask Jourdan Taylor Holder Duane Varan 《Mass Communication and Society》2014,17(2):195-216
The study at hand employed a pre- versus posttest experimental design to test the effects of television drama Switched at Birth on viewers’ attitudes toward deafness. This program tells the story of two teenage girls (one of whom is deaf) and their struggles to relate to their peers and families after discovering they were switched as newborns. Two hundred eleven female adults completed pre- and postexposure measures utilizing Cooper, Rose, and Mason's (2004) Attitudes to Deafness measure, the items of which were categorized according to thematic dimensions. After exposure to one of three episodes, viewers’ attitudes toward deafness significantly improved overall, although significant differences in attitude changes varied by episodes and dimensions. The three thematic dimensions that were most strongly represented in the program (social interaction, deafness as a handicap, and language issues) appeared to show the strongest attitude change. Positive attitude changes were observed on social interaction and deafness as handicap dimensions, which was consistent with program content depicting positive deaf-hearing friendships and capable deaf characters. However, attitudes on the language issues dimension showed a negative shift, possibly due to the way that deaf characters communicated with hearing characters onscreen. 相似文献
5.
《Government Information Quarterly》2014,31(4):534-544
This paper investigates how text analysis and classification techniques can be used to enhance e-government, typically law enforcement agencies' efficiency and effectiveness by analyzing text reports automatically and provide timely supporting information to decision makers. With an increasing number of anonymous crime reports being filed and digitized, it is generally difficult for crime analysts to process and analyze crime reports efficiently. Complicating the problem is that the information has not been filtered or guided in a detective-led interview resulting in much irrelevant information. We are developing a decision support system (DSS), combining natural language processing (NLP) techniques, similarity measures, and machine learning, i.e., a Naïve Bayes' classifier, to support crime analysis and classify which crime reports discuss the same and different crime. We report on an algorithm essential to the DSS and its evaluations. Two studies with small and big datasets were conducted to compare the system with a human expert's performance. The first study includes 10 sets of crime reports discussing 2 to 5 crimes. The highest algorithm accuracy was found by using binary logistic regression (89%) while Naive Bayes' classifier was only slightly lower (87%). The expert achieved still better performance (96%) when given sufficient time. The second study includes two datasets with 40 and 60 crime reports discussing 16 different types of crimes for each dataset. The results show that our system achieved the highest classification accuracy (94.82%), while the crime analyst's classification accuracy (93.74%) is slightly lower. 相似文献
6.
7.
We augment naive Bayes models with statistical n-gram language models to address short-comings of the standard naive Bayes text classifier. The result is a generalized naive Bayes classifier which allows for a local Markov dependence among observations; a model we refer to as the C hain A ugmented N aive Bayes (CAN) Bayes classifier. CAN models have two advantages over standard naive Bayes classifiers. First, they relax some of the independence assumptions of naive Bayes—allowing a local Markov chain dependence in the observed variables—while still permitting efficient inference and learning. Second, they permit straightforward application of sophisticated smoothing techniques from statistical language modeling, which allows one to obtain better parameter estimates than the standard Laplace smoothing used in naive Bayes classification. In this paper, we introduce CAN models and apply them to various text classification problems. To demonstrate the language independent and task independent nature of these classifiers, we present experimental results on several text classification problems—authorship attribution, text genre classification, and topic detection—in several languages—Greek, English, Japanese and Chinese. We then systematically study the key factors in the CAN model that can influence the classification performance, and analyze the strengths and weaknesses of the model. 相似文献
8.
Massih R. Amini Anastasios Tombros Nicolas Usunier Mounia Lalmas 《Information Retrieval》2007,10(3):233-255
Documents formatted in eXtensible Markup Language (XML) are available in collections of various document types. In this paper,
we present an approach for the summarisation of XML documents. The novelty of this approach lies in that it is based on features
not only from the content of documents, but also from their logical structure. We follow a machine learning, sentence extraction-based
summarisation technique. To find which features are more effective for producing summaries, this approach views sentence extraction
as an ordering task. We evaluated our summarisation model using the INEX and SUMMAC datasets. The results demonstrate that
the inclusion of features from the logical structure of documents increases the effectiveness of the summariser, and that
the learnable system is also effective and well-suited to the task of summarisation in the context of XML documents. Our approach
is generic, and is therefore applicable, apart from entire documents, to elements of varying granularity within the XML tree.
We view these results as a step towards the intelligent summarisation of XML documents.
相似文献
| Mounia LalmasEmail: |
9.
Donato Tamblé 《Archival Science》1987,1(1):83-100
Archival theory in Italy has a long tradition, going back as far as the second half of the nineteenth century, and with roots
in the 17th and 18th centuries. Central theme in the theory is themetodo storico, the principle of provenance, for the first time expressed in the late 19th century by Bonaini and Bongi. In the following
decades archivists like Casanova and Cencetti were among the leading authors. Elio Lodolini assigned himself the task to synthesize
ideas and notions, within a clear distinctions between records (registratura) and archives. One of the overall characteristics
of the rich Italian literature is the stressing of the cultural value of archives.
I have twice treated before the theme of archival theory in Italy from the fifties up to the nineties. The first time on the
occasion of the 25th anniversary of theScuola speciale per Archivisti e Bibliotecari dell'Università degli Studi “La Sapienza” di Roma in 1989, when there was an international round table on archival science in the State Archives of Rome. My essay,Italian archival science today, has been published in the proceedings of the meeting (cfr. Donato Tamblé,L'archivistica in Italia oggi, inStudi sull'archivistica, by Roma: Elio Lodolini, 1992). Some years later, in 1993, I published a book on contemporary Italian archival theory (Donato
Tamblé,La teoria archivistica italiana contemporanea (1950–1990). Profilo storico-critico (Roma, 1993) which was the sequel to the volume of Elio Lodolini on Italian archival history — (Lineamenti di storia dell'archivistica italiana (Roma, 1991). The purpose of my book was that of locating and identifying the scientific object of archival science as it
developed and was clarified in the thinking and in the lucubration of the contemporary Italian Archivists. 相似文献
10.
Donato Tamblé 《Archival Science》2001,1(1):83-100
Archival theory in Italy has a long tradition, going back as far as the second half of the nineteenth century, and with roots
in the 17th and 18th centuries. Central theme in the theory is themetodo storico, the principle of provenance, for the first time expressed in the late 19th century by Bonaini and Bongi. In the following
decades archivists like Casanova and Cencetti were among the leading authors. Elio Lodolini assigned himself the task to synthesize
ideas and notions, within a clear distinctions between records (registratura) and archives. One of the overall characteristics
of the rich Italian literature is the stressing of the cultural value of archives.
I have twice treated before the theme of archival theory in Italy from the fifties up to the nineties. The first time on the
occasion of the 25th anniversary of theScuola speciale per Archivisti e Bibliotecari dell'Università degli Studi “La Sapienza” di Roma in 1989, when there was an international round table on archival science in the State Archives of Rome. My essay,Italian archival science today, has been published in the proceedings of the meeting (cfr. Donato Tamblé,L'archivistica in Italia oggi, inStudi sull'archivistica, by Roma: Elio Lodolini, 1992). Some years later, in 1993, I published a book on contemporary Italian archival theory (Donato
Tamblé,La teoria archivistica italiana contemporanea (1950–1990). Profilo storico-critico (Roma, 1993) which was the sequel to the volume of Elio Lodolini on Italian archival history — (Lineamenti di storia dell'archivistica italiana (Roma, 1991). The purpose of my book was that of locating and identifying the scientific object of archival science as it
developed and was clarified in the thinking and in the lucubration of the contemporary Italian Archivists. 相似文献
11.
Shing-Chung Jonathan Yam 《传播与批判/文化研究》2016,13(3):305-323
Although previous research has revealed factors that affect Wikipedia editors' decisions regarding content retainment and deletion,1 there has been little research on the editors' discussion that is involved therein as a linguistic process. In this article, I study Wikipedia's Articles for Deletion (AfD) talk pages and conceptualize each discussion as a conflictual language game.2 I study, by using discourse analysis interpretively and critically, how participants (especially first movers) frame the discussion direction—either as an invitation to collaborate or with cascading arguments (leaving little room for casual chit-chat). Finally, I study entire AfD discussions and find two coexisting language games: the discussion game and the consultation/enforcement game. I find that the closing admins of AfD discussions function as policy experts rather than consensus facilitators. Hence, AfD discussions contain both sets of game rules, but ultimately the power of the decision is nonetheless vested in the admins. This brings background power dynamics into the grammar of language games in the struggle for the generation and sustenance of the dominant knowledge or narratives of our information society. 相似文献
12.
We investigate temporal factors in assessing the authoritativeness of web pages. We present three different metrics related
to time: age, event, and trend. These metrics measure recentness, special event occurrence, and trend in revisions, respectively.
An experimental dataset is created by crawling selected web pages for a period of several months. This data is used to compare
page rankings by human users with rankings computed by the standard PageRank algorithm (which does not include temporal factors)
and three algorithms that incorporate temporal factors, including the Time-Weighted PageRank (TWPR) algorithm introduced here. Analysis of the rankings shows that all three temporal-aware algorithms produce rankings more
like those of human users than does the PageRank algorithm. Of these, the TWPR algorithm produces rankings most similar to human users’, indicating that all three temporal factors are relevant in page
ranking. In addition, analysis of parameter values used to weight the three temporal factors reveals that age factor has the
most impact on page rankings, while trend and event factors have the second and the least impact. Proper weighting of the
three factors in TWPR algorithm provides the best ranking results. 相似文献
13.
《Communication monographs》2012,79(3):287-310
Collaborative partnerships developed via text-based computer-mediated communication (CMC) commonly shift interactions to alternative formats. Extant research indicates that shifting from one modality to another, or “modality switching,” can have profound positive and negative effects on relational outcomes. Drawing on social presence theory (Short, Williams, & Christie, 1976) and social information processing theory (SIPT; Walther, 1992, 1996), the present study examined the influence of meeting FtF after varying lengths of time interacting via CMC on relational communication. Consistent with predictions, remaining online yielded greater intimacy and social attraction than the other conditions in which FtF contact occurred. With respect to the CMC conditions, modality switching modestly enhanced relational outcomes in the “early” switching partnerships but more strongly dampened those of “late” switching ones. 相似文献
14.
On information retrieval metrics designed for evaluation with incomplete relevance assessments 总被引：1，自引：0，他引：1
Modern information retrieval (IR) test collections have grown in size, but the available manpower for relevance assessments
has more or less remained constant. Hence, how to reliably evaluate and compare IR systems using incomplete relevance data, where many documents exist that were never examined by the relevance assessors, is receiving a lot of attention.
This article compares the robustness of IR metrics to incomplete relevance assessments, using four different sets of graded-relevance
test collections with submitted runs—the TREC 2003 and 2004 robust track data and the NTCIR-6 Japanese and Chinese IR data
from the crosslingual task. Following previous work, we artificially reduce the original relevance data to simulate IR evaluation
environments with extremely incomplete relevance data. We then investigate the effect of this reduction on discriminative power, which we define as the proportion of system pairs with a statistically significant difference for a given probability of
Type I Error, and on Kendall’s rank correlation, which reflects the overall resemblance of two system rankings according to two different metrics or two different relevance
data sets. According to these experiments, Q′, nDCG′ and AP′ proposed by Sakai are superior to bpref proposed by Buckley and
Voorhees and to Rank-Biased Precision proposed by Moffat and Zobel. We also point out some weaknesses of bpref and Rank-Biased
Precision by examining their formal definitions.
相似文献
| Noriko KandoEmail: |
15.
Bibliometric data indexed through the Institute for Scientific Information were analyzed for 45 communication journals. Several measures were included to identify the most widely cited journals in the field, including (a) journal impact factor, (b) five-year journal impact, (c) article influence, and (d) journal relatedness. Results serve to expand on findings by Feeley (2008) with respect to overall and within-field influence of communication journals whose analysis covered 2002 through 2005 and 19 journals. Results indicate stability in journal impact ratings over time and several journals (e.g., Communication Research, Human Communication Research, Journal of Communication, Communication Monographs, and Communication Theory) are highly central in the communication journal citation network. 相似文献
16.
Sentence level novelty detection aims at spotting sentences with novel information from an ordered sentence list. In the task, sentences appearing later in the list with no new meanings are eliminated. For the task of novelty detection, the contributions of this paper are three-fold. First, conceptually, this paper reveals the computational nature of the task currently overlooked by the Novelty community—Novelty as a combination of partial overlap (PO) and complete overlap (CO) relations between sentences. We define partial overlap between two sentences as a sharing of common facts, while complete overlap is when one sentence covers all of the meanings of the other sentence. Second, technically, a novel approach, the selected pool method is provided which follows naturally from the PO-CO computational structure. We provide formal error analysis for selected pool and methods based on this PO-CO framework. We address the question how accurate must the PO judgments be to outperform the baseline pool method. Third, experimentally, results were presented for all the three novelty datasets currently available. Results show that the selected pool is significantly better or no worse than the current methods, an indication that the term overlap criterion for the PO judgments could be adequately accurate.
相似文献
| Shaoping MaEmail: |
17.
Danielle Catona Kathryn Greene Kate Magsamen-Conrad Amanda Carpenter 《Journal of Applied Communication Research》2016,44(2):136-155
HIV remains a significant health concern entering the fourth decade of the epidemic [Centers for Disease Control and Prevention. 2014. HIV basics. Retrieved from http://www.cdc.gov/hiv/basics/index.html], and people living with HIV continue to grapple with stigma. This study uses Leary and Schreindorfer's [1998. The stigmatization of HIV and AIDS: Rubbing salt in the wound. In V. J. Derlega &; A. P. Barbee (Eds.), HIV and social interaction (pp. 12–29). Thousand Oaks, CA: Sage] conceptualization of stigma to explore prior stigmatization on reasons for and against future disclosures. We interviewed HIV+ individuals (N?=?59) and used a combination of deductive and inductive coding to analyze participants’ responses. Deductive codes consisted of four stigma characteristics (pose a threat to others’ health and safety, deviate from group standards, create negative emotional reactions in others, and failure to contribute), experiences of feeling stigmatized due to HIV status (yes or no), and the degree to which HIV stigma was a concern (major, minor, or no concern). Inductive coding identified examples of perceived and experienced stigma and stigma concerns on future disclosure decision-making. Practical implications discuss individual, institutional, and societal stigma-reduction interventions and programs. 相似文献
18.
Strategic Communication during Marital Relationship Dissolution: Disengagement Resistance Strategies
Merry C. Buchanan H. Dan O'Hair Jennifer A. H. Becker 《Communication Research Reports》2013,30(3):139-147
This study investigated the communication strategies used by divorced individuals who did not wish their marriages to end (non-initiators). Participants were 270 divorced persons drawn from divorce recovery and support groups as well as network sampling. An adaptation of Buss's (1988) taxonomy of partner retention tactics served to capture the communication strategies of non-initiators during marital dissolution. A factor analysis revealed that four disengagement resistance strategies—commitment, alignment, negativity, and harm—are used by non-initiators during the process of marital dissolution. 相似文献
19.
Irving Louis Horowitz 《Publishing Research Quarterly》1995,11(1):40-45
Upon reviewing thePreliminary Draft of the Report of the Working Group on Intellectual Property Rights, given the titleIntellectual Property and the National Information Infrastructure, one immediately confronts the grand ambiguity that resides in the two words: “intellectual property.” That the task force
on the information infrastructure, enshrined with the acronym NII, had to locate precedent for its missioning Supreme Court
Justice Story's 1841 observations on copyright issues as an area involving the “metaphysics of the law” indicates what a long
reach the very notion of intellectual property entails in a democratic society.
He is the author ofCommunicating Ideas: The Politics of Publishing and has published widely in the journal literature, includingScholarly Publishing; Logos; Publishing Research Quarterly; Journal of the American Society of Information Science, among others. 相似文献
20.
《Journal of Radio & Audio Media》2013,20(2):150-166
This study found support for the Schwartz (1994) two-value political ideology model in relation to political talk radio (PTR) program choice. People who listened to liberal PTR hosts were found to be associated with “universalism.” People who listened to conservative PTR hosts were found to be associated with “security.” Additional values were also found to be associated with listening to liberal and conservative PTR hosts. In addition, discriminant analysis was used to develop a model which could predict PTR listening based on audience values. These findings add to the understanding of the uses and gratifications of listening to political talk radio. 相似文献