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The Study of Applying Category Management on Adaptive Customer-centered Online CatalogsLiu, Chiang-Luan 26 June 2001 (has links)
The Internet with growing electronic commerce is regarded as
a new selling channel for retailers. Online catalog organization has
become an important issue for e-tailing business development.
While most online retailing web sites provide assistance for
searchers who know exactly what they are seeking, little has been
done to aid browsers who take a more open-minded and
exploratory approach to navigation. Good design of online catalogs
is essential for browsers to shop over the web.
In this paper, we propose a two-phase approach to the design
of online catalogs. In the first phase, the idea of category
management that analyzes customers¡¦ purchasing behaviors is
employed to construct a customer-centered online catalog.
Cluster-based market segmentation helps determine the web
hierarchy with clusters of products in higher levels indicating more
interesting to customers. The second phase is to dynamically adjust
the hierarchy when customers¡¦ preference indicated by browsing
patterns is changed.'Relative access' that reflects the popularity of
web pages is used as a basis to make online catalog adaptation.
Finally, we apply this approach to real-world data collected at
Galleze.com by Blue Martini Software. It shows that our approach
can result in meaningful online catalog organization for customers
to navigate. Our study therefore provides a good direction for
researchers in designing online catalogs. Furthermore, e-tailing
practitioners can apply our approach easily and gain benefits from
such a design.
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Local and disjointness structures of smooth Banach manifoldsWang, Ya-Shu 26 December 2009 (has links)
Peetre characterized local operators defined on the smooth section space over an open subset of an Euclidean space as ``linear differential operators'. We look for an extension to such maps of smooth vector sections of smooth Banach bundles. Since local
operators are special disjointness preserving operators, it leads to the study of the disjointness structure of smooth Banach manifolds.
In this thesis, we take an abstract approach to define the``smooth functions', via the so-called S-category.
Especially, it covers the standard classes C^{n} and local Lipschitz functions, where 0≤n≤¡Û. We will study
the structure of disjointness preserving linear maps between S-smooth functions defined on separable Banach manifolds. In particular, we will give an extension of Peetre's theorem to characterize disjointness preserving linear mappings between C^n
or local Lipschitz functions defined on locally compact metric spaces.
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Neuropsychology of Semantic Memory: Theories, Models, and TestsLaurila, Linda January 2007 (has links)
<p>Semantic memory is part of the long-term memory system, and there are several theories concerning this type of memory. Some of these will be described in this essay. There are also several types of neuropsychological semantic memory deficits. For example, test results have shown that patients tend to have more difficulties naming living than nonliving things, and one probable explanation is that living things are more dependent on sensory than on functional features. Description of concrete concepts is a new test of semantic memory, in which cueing is used, both to capture the maximum performance of patients, and to give insight into the access versus storage problem. The theoretical ideas and empirical results relating to this new test will be described in detail. Furthermore, other tests of semantic memory that have been commonly used will also be briefly described. In conclusion semantic memory is a complex cognitive system that needs to be studied further.</p>
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Some problems in algebraic topology : on Lusternik-Schnirelmann categories and cocategoriesGilbert, William J. January 1967 (has links)
In his thesis we are concerned with certain numerical invariants of homotopy type akin to the Lusternik-Schnirelmann category and cocategory. In a series of papers I. Bernstein, T. Ganea, and P.J. Hilton developed the concepts of the category and weak category of a topological space. They also considered the related concepts of conilpotency and cup product length of a space and the weak category of a map. Later T. Ganea gave another definition of category and weak category (which we shall write as G-cat and G-wcat) in terms of vibrations and cofibrations and hence this dualizes easily in the sense of Eckmann-Hilton. We find the relationships between these invariants and then find various examples of spaces which show that the invariants are all different except cat and G-cat. The results are contained in the following theorem. The map $e:B -> OmegaSigma B$ is the natural embedding. All the invariants are normalized so as to take the value 0 on contractible spaces. THEOREM Let B have the homotopy type of a simply connected CW-complex, then $cat B = G-cat B geq G-wcat B geq wcat B geq wcat e geq conil B geq cup-long B$ and furthermore all the inequalities can occur. All the examples are spaces of the form $B = S^qcup_alpha e^n$ where $alphain pi_{n-1} (S^q)$. When B is of this form, we obtain conditions for the category and the weak categories of B to be less than or equal to one of the terms of Hopf invariants of $alpha$. We use these conditions to prove the examples. We then prove the dual theorem concerning the relationships between the invariants cocategory, weak cocategory, nilpotency and Whitehead product length. THEOREM Let A be countable CW-complex, then $cocat A geq wcocat A geq nil A geq W-long A$ and furthermore all the inequalities can occur. The proof is not dual to the first theorem, though the examples we use to show that the inequalities can exist are all spaces with two non-zero homotopy groups. The most interesting of these examples is the space A with 2 non-zero homotopy groups, $mathbb Z$ in dimension 2 and ${mathbb Z}_4$ in dimension 7 with k-invariant $u^4 in H^8(mathbb Z, 2; {mathbb Z}_4)$. This space is not an H-space, but has weak cocategory 1. The condition $wcocat A leq 1$ is equivalent to the fact that d is homotopic to 0 in the fibration $D -d-> A -e-> OmegaSigma A$. In order to show that wcocat A = 1 we have to calculate to cohomology ring of $OmegaSigma K(mathbb Z,2)$. The method we use to do this is the same as that used to calculate the cohomology ring of $OmegaSigma S^{n+1}$ using James' reduced product construction. Finally we show that for the above space A the fibration $Omega A -g-> A^S -f-> A$ has a retraction $ ho$ such that $ hocirc g$ is homotopic to 1 even though A is not an H-space.
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Functional Query Languages with Categorical TypesWisnesky, Ryan 25 February 2014 (has links)
We study three category-theoretic types in the context of functional query languages (typed lambda-calculi extended with additional operations for bulk data processing). The types we study are: / Engineering and Applied Sciences
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A Modular Theory of Radical Pro DropLiu, Chi-Ming Louis 04 June 2015 (has links)
Mandarin Chinese is said to be a radical pro-drop language, in the sense that verbal arguments in this language can be dropped rather freely. However, in this dissertation, I show that the omission of arguments in Mandarin Chinese is in fact constrained by various conditions. First, I demonstrate that the availability of a discourse topic is insufficient to license empty categories in Mandarin Chinese by showing that subject and object positions cannot be left empty at random. Some empty subject positions are neither true instances of nominal ellipsis nor variables bound by discourse topics; instead, they are a side effect of verb or vP movement followed by TP-ellipsis. Next, I address the issue of when objects can be "dropped" in Mandarin Chinese. I argue that structural parallelism built on verbal identity between sentences plays an important role in licensing `objectless' sentences. I propose that the mechanism responsible for the creation of such sentences is V-stranding VP-ellipsis rather than argument ellipsis. In the last part of this dissertation, I show that, although we cannot rely on the strength of discourse alone to account for empty categories, the concept of topic-hood is nevertheless implicated in the appearance of certain empty argument positions in sentences used in monologues. I claim that subject pro in Mandarin Chinese must have as its antecedent an element located in an A'-position, which can be overt or covert. In addition, I suggest that the differences between Italian, Japanese, and Mandarin Chinese with respect to the use of subject pro can be boiled down to the featural properties of the covert topic TOP preceding subject pro: this covert topic has inherently valued phi-features in Italian and Japanese, while its counterpart in Mandarin Chinese does not. / Linguistics
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Generative naming in Korean-English bilingual speakersKim, Sueun 20 December 2010 (has links)
This present study investigated generative naming in Korean-English bilingual adult speakers. Specific aims were: 1) to compare the total number of named items generated in Korean-English bilingual adults in the categories of Food, Clothes, and Animals, 2) to investigate the relationship between language proficiency and the total number of items named in each category and across categories for each language, and 3) to examine the relationship between language proficiency and the total number of overlapped items (doublets) in each category and across categories. Twenty five Korean-English bilingual adults named as many different items as they could in 60 seconds in the categories of Food, Clothes, and Animals in Korean and English. Results indicated that the participants produced significantly more items in Korean than English in all categories. Participants named fewer items in the category of Clothes than in the categories of Food and Animals, suggesting that generating items for the Clothes category was more difficult than for the other categories. No significant correlations were found between participants’ language proficiency and the total number of items generated and the number of doublets. There is a need to develop more reliable measures of language proficiency for bilingual speakers. / text
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The application of machine learning methods in software verification and validationPhuc, Nguyen Vinh, 1955- 04 January 2011 (has links)
Machine learning methods have been employed in data mining to discover useful, valid, and beneficial patterns for various applications of which, the domain encompasses areas in business, medicine, agriculture, census, and software engineering. Focusing on software engineering, this report presents an investigation of machine learning techniques that have been utilized to predict programming faults during the verification and validation of software. Artifacts such as traces in program executions, information about test case coverage and data pertaining to execution failures are of special interest to address the following concerns: Completeness for test suite coverage; Automation of test oracles to reduce human intervention in Software testing; Detection of faults causing program failures; Defect prediction in software. A survey of literature pertaining to the verification and validation of software also revealed a novel concept designed to improve black-box testing using Category-Partition for test specifications and test suites. The report includes two experiments using data extracted from source code available from the website (15) to demonstrate the application of a decision tree (C4.5) and the multilayer perceptron for fault prediction, and an example that shows a potential candidate for the Category-Partition scheme. The results from several research projects shows that the application of machine learning in software testing has achieved various degrees of success in effectively assisting software developers to improve their test strategy in verification and validation of software systems. / text
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The Hierarchical Condition Category Model - an Improved Comorbidity Adjustment Tool for Predicting Mortality in Medicare Populations?Mosley, David Glen. January 2013 (has links)
BACKGROUND: Morbidity, defined as disease history, is an important and well-known confounder in epidemiologic studies. Numerous methods have been developed over the last 30 years to measure morbidity via valid and reliable processes. OBJECTIVE: The goal of the current study was to evaluate, via comparative predictive validity assessment, the Centers for Medicaid and Medicare Studies Hierarchical Condition Category (CMS-HCC) comorbidity model for its ability to improve the prediction of 12-month all-cause mortality among a Medicare population compared to previously published comorbidity index models. There were three specific aims: (1) challenge the current state of risk adjustment among aged populations via an evaluation of the comparative predictive validity of one novel and four existing models to predict all-cause mortality within 12 months among a heterogeneous population of Medicare beneficiaries; (2) Investigate the comparative predictive validity of the five models to predict all-cause mortality within 12 months among two homogenous populations diagnosed with ischemic heart disease and selected cancers, including prostate cancer, lung cancer, colorectal cancer, breast cancer, pancreas cancer, and endometrial cancer; and (3) measure each comorbidity model's ability to control for a known example of confounding by indication. METHODS: A retrospective cohort design was used for all specific aims. Study 1 included 257,641 Medicare beneficiaries enrolled in three Medicare Advantage prescription drug health plans in Alabama, Florida, or Ohio in 2010 and 2011. Study 2 limited analysis to 14,260 and 66,440 beneficiaries with administrative evidence of selected cancers or ischemic heart disease in 2010, respectively. Study 3 limited analysis to the beneficiaries with ischemic heart disease. For each participant, comorbidity risk scores for the following five models were generated using administrative data from 2010: an age/sex model, the Romano adaption of the Charlson Comorbidity Index (CCI) model, the Putnam adaptation of the Chronic Disease Score Model (CDS), the CMS version of the Hierarchical Condition Category (CMS-HCC) model, and the Agency for Healthcare Research and Quality (AHRQ) adaptation of the Elixhauser model. The prospective predictive validity of the models to predict all-cause mortality during 2011 was compared via the c statistic test. Participants with ischemic heart disease were randomly allocated retrospectively to either 1) a group that had "received" a hypothetical "Drug A" in 2010 or 2) a group that had "received" a hypothetical "Drug B" in 2010. In order to evaluate the impact of confounding by indication, a weighting factor was applied to the randomization process in order to force the 33,220 participants randomized to "Drug A" to have a 2.736 times higher likelihood of having at least one acute inpatient hospitalization in 2010. Each comorbidity model's ability to control for the contrived confounding by indication was evaluated via relative risk of death. RESULTS: The CMS-HCC model had statistically significant higher c-statistic values than all four existing comorbidity indices among the heterogeneous Medicare Advantage population (N=257,641) and the homogeneous populations with breast cancer (N=4,160) and prostate cancer (N=6,594). The CMS-HCC model displayed similar performance for lung cancer (N=1,384), colorectal cancer (N=1,738), endometrial cancer (N=232), and ischemic heart disease (N=66,640) and statistically significant lower performance for pancreas cancer (N=152). The log-transformed CMS-HCC model was the only model to generate a non-significant association between exposure to "Drug A" and subsequent mortality. CONCLUSION: In general, the CMS-HCC model is the preferred comorbidity measure due to its predictive performance. However, other comorbidity models may be optimal for diseases with low prevalence and/or high mortality. Researchers should carefully and thoughtfully select a comorbidity model to assess the existence and direction of confounding. The CMS-HCC model should be log-transformed when used as a dependent variable since the score is a ratio level measurement that displays a normal distribution when log transformed. The resulting score is less likely to violate the assumptions (i.e. violations of normality) of common statistical models due to extreme values. The national availability of CMS-HCC scores for all Medicare beneficiaries provides researchers with access to a new tool to measure co-morbidity among older Americans using an empirically weighted, single score. In terms of policy, it is recommended that CMS produce CMS-HCC scores for all Medicare beneficiaries on a rolling 12 month basis for each month during the year. The availability of monthly scores would increase the ease of use of the score, as well as help facilitate more rapid adoption of the tool.
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Relations in Models of Calculi and Logics with NamesYemane, Kidane January 2006 (has links)
In this thesis we investigate two operational models of name-passing calculi: one based on coalgebra, and one based on enriched automata. We develop a semantic framework for modelling the open bisimulation in π-calculus, hyperbisimulation in Fusion calculus, and the first semantic interpretation of FOλ(nabla) logic. We consider a category theoretic model where both “variables” and “names”, usually viewed as separate notions, are particular cases of the more general notion of atoms. The key aspect of this model is to consider functors over the category of irreflexive and symmetric finite relations. The models previously proposed for the separate notions of “variables” and “names” embed faithfully in the new one, and initial algebra/final coalgebra constructions can be transferred from the formers to the latter. Moreover, the new model admits a definition of distinction-aware simultaneous substitutions. As a substantial application example, we give the first semantic interpretation of Miller-Tiu's FOλ(nabla) logic. FOλ(nabla) logic is designed for reasoning about operational semantics of languages with binding. On the operational level, a contribution of the thesis is to extend an automata-based model for a variety of name-passing calculi with their associated notion of equivalence. HD-automata, a syntax-independent operational model, has been successfully applied for modelling e.g. early and late bisimulation in π-calculus and hyperbisimulation in Fusion calculus. However, current HD-automata are not adequate for modelling open bisimulation because they can not handle distinction-preserving substitutions. We solve this technical problem by integrating the notion of distinction into the definition of named sets, the basic building blocks of HD-automata. Finally, we discuss the relationship between HD-automata with distinctions, and D-LTS.
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