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Effects of Using Examples on Structural Model Comprehension: A Controlled ExperimentZayan, Dina January 2013 (has links)
We present a controlled experiment for the empirical evaluation of Example-Driven
Modeling (EDM), an approach that systematically uses examples for model comprehension and domain knowledge transfer. We conducted the experiment with 26 graduate and undergraduate students from electrical and computer engineering (ECE), computer science (CS), and software engineering (SE) programs at the University of Waterloo. The experiment involves a domain model, with a UML class diagram representing the domain abstractions and UML object diagrams representing examples of using these abstractions. The goal is to provide empirical evidence of the effects of suitable examples on model comprehension, compared to having model abstractions only, by having the participants perform model comprehension tasks. Our results show that EDM is superior to having model abstractions only, with an improvement of (+39%) for diagram completeness, (+30%) for study questions completeness, (+71%) for efficiency, and a reduction of (-80%) for the number of mistakes. We provide qualitative results showing that participants receiving model abstractions augmented with examples experienced lower perceived difficulty in performing the comprehension tasks, higher perceived confidence in their tasks' solutions, and asked fewer clarifying domain questions (a reduction of 90%). We also present participants' feedback
regarding the usefulness of the provided examples, the number of examples, the types
of examples, and the use of partial examples.
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Investigating a Common Structure of Personality Pathology and AttachmentMadison S Smith (10732413) 05 May 2021 (has links)
<p>Attachment and personality disorders (PDs) both describe patterns of interpersonal dysfunction. Indeed, there are many similarities and few differences between these constructs, suggesting that they may represent two iterations of a common dimension. However, the paucity of empirical tests on this topic has precluded integration of clinical efforts. Also limiting clinical efforts is the inability to target individuals and relationships most prone to dysfunction. The current study used a large sample (N=812) of unselected undergraduates (N=355) and adults currently in psychological treatment (N=457) to test whether a joint hierarchical factor structure of attachment and PDs is tenable and whether it varies reliably by gender, treatment status, or attachment figure. Results suggested that attachment and PDs can be quantified jointly in specific instances of emotional lability and detachment, but attachment was not isomorphic with antagonistic, impulsigenic, or psychosis-spectrum traits. This joint structure was relatively consistent across attachment figures and treatment status but varied somewhat across gender. Clinical applications of these findings on commonalities of interpersonal dysfunction are discussed. </p>
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Modeling and Analysis of Software Product Line Variability in ClaferBak, Kacper 24 October 2013 (has links)
Both feature and class modeling are used in Software Product Line (SPL) engineering to model variability. Feature models are used primarily to represent user-visible characteristics (i.e., features) of products; whereas class models are often used to model types of components and connectors in a product-line architecture.
Previous works have explored the approach of using a single language to express both configurations of features and components. Their goal was to simplify the definition and analysis of feature-to-component mappings and to allow modeling component options as features. A prominent example of this approach is cardinality-based feature modeling, which extends feature models with multiple instantiation and references to express component-like, replicated features. Another example is to support feature modeling in a class modeling language, such as UML or MOF, using their profiling mechanisms and a stylized use of composition. Both examples have notable drawbacks: cardinality-based feature modeling lacks a constraint language and a well-defined semantics; encoding feature models as class models and their evolution bring extra complexity.
This dissertation presents Clafer (class, feature, reference), a class modeling language with first-class support for feature modeling. Clafer can express rich structural models augmented with complex constraints, i.e., domain, variability, component models, and meta-models. Clafer supports: (i) class-based meta-models, (ii) object models (with uncertainty, if needed), (iii) feature models with attributes and multiple instantiation, (iv) configurations of feature models, (v) mixtures of meta- and feature models and model templates, and (vi) first-order logic constraints.
Clafer also makes it possible to arrange models into multiple specialization and extension layers via constraints and inheritance. On the other hand, in designing Clafer we wanted to create a language that builds upon as few concepts as possible, and is easy to learn. The language is supported by tools for SPL verification and optimization.
We propose to unify basic modeling constructs into a single concept, called clafer. In other words, Clafer is not a hybrid language. We identify several key mechanisms allowing a class modeling language to express feature models concisely. We provide Clafer with a formal semantics built in a novel, structurally explicit way. As Clafer subsumes cardinality-based feature modeling with attributes, references, and constraints, we are the first to precisely define semantics of such models.
We also explore the notion of partial instantiation that allows for modeling with uncertainty and variability. We show that Object-Oriented Modeling (OOM) languages with no direct support for partial instances can support them via class modeling, using subclassing and strengthening multiplicity constraints. We make the encoding of partial instances via subclassing precise and general. Clafer uses this encoding and pushes the idea even further: it provides a syntactic unification of types and (partial) instances via subclassing and redefinition.
We evaluate Clafer analytically and experimentally. The analytical evaluation shows that Clafer can concisely express feature and meta-models via a uniform syntax and unified semantics. The experimental evaluation shows that: 1) Clafer can express a variety of realistic rich structural models with complex constraints, such as variability models, meta-models, model templates, and domain models; and 2) that useful analyses can be performed within seconds.
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Essays on Inertia, Dynamics and Market CompetitionFleitas Perla, Sebastian, Fleitas Perla, Sebastian January 2017 (has links)
The central goal of my dissertation is to answer important questions about market design in health care when consumers have inertia, using modern industrial organization tools. The presence of consumer inertia in several markets has been well established in the literature, although we still know very little about how inertia affects the way markets work. In my dissertation, I shed light on these issues in the context of different institutional settings of health care sectors in different countries. Health care markets are extremely relevant because of their huge impacts on the quality of life and on mortality of individuals. In times when the expenditure on health care is increasingly high in modern economies, a better understanding of how these markets work is needed in order to decrease costs and improve their performance. The first chapter disentangles the effects of reductions in switching costs and in the length of contracts (lock-in) on consumer welfare, using quasi-experimental variation in the length of contracts in the Uruguayan health care system. In the second chapter, I study the effect of supply-side firm responses in terms of pricing and offering of new products, on consumer welfare in Medicare Part D in the U.S. Finally, the third chapter studies the effects of increased competition induced by reductions of consumer inertia, on quality and returns to skills for physicians, using uniquely detailed data from the Uruguayan health care sector. The use of tools from the field of industrial organization allows me to combine a solid theoretical background with clearly identified reduced-form and structural models, to analyze the welfare implications of equilibrium behavior in these markets, and to evaluate policy interventions and regulations aimed at improving welfare.
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SUPPLIER SELECTION METRICS AND METHODOLOGYKESKAR, HARSHAL S. 01 July 2004 (has links)
No description available.
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ESSAYS ON PRICE DISCRIMINATION AND DEMAND LEARNINGWallace, Benjamin E. 01 January 2019 (has links)
This dissertation consists of three essays examining how and why firms set prices in markets. In particular, this dissertation shows how firms may utilize nonlinear pricing to price discriminate, how firms may experiment with the prices they set to learn about the demand function in the market they serve in later periods and the effects of these pricing strategies on consumer welfare.
In Essay 1, I show how firms in the milk market use nonlinear price schedules -- quantity discounts -- to price discriminate and increase profits. I find that firms have a greater ability to price discriminate on their own ``private label'' products rather than regional branded that they sell alongside their own. Though some consumers benefit from a lower price as a result of the price discrimination, total consumer surplus is lower than if the store had to offer a fixed price per unit. Additionally, I compare my structural demand estimates, which using the Nielsen household panel data include consumer demographic information and actual household choices, to the standard approach in the literature on price discrimination that uses only market level data. By doing so I find that ignoring demographic information and actual consumer choices leads to biased parameter estimates. In the case of the milk market, the biased parameter estimates due to ignoring household demographic information and actual consumer choices lead to underestimating welfare harm to consumers on average.
After finding that price discrimination harms consumers overall in this market, I quantify which consumer demographic are better off and which are worse off. I find that households with children and low income households with children are the only households to benefit from the price discriminatory practices of firms in this market. Since these groups are particularly vulnerable, I suggest that policymakers take no action to correct this market, as any action will directly hurt these consumer groups.
In Essay 2, I study how firms learn about the demand in a new market by exploiting a significant change in Washington's state's liquor laws. In 2012, the state of Washington switched from a price-controlled state-store system of selling liquor to one in which private sellers could sell liquor with minimal restrictions on price and range of products. As a result, a heterogeneous group of firms entered the liquor market across the state with little knowledge of the regional demand for alcohol in the state of Washington across heterogeneous localities. Using the Nielsen retail scanner data I am able to observe the variation in pricing and offerings seasonally and over time to see if there is convergence in offerings and prices, and how quickly that convergence occurs across different localities depending on local demographics and competition. I also investigate the extent to which the variation is "experimentation'' by the firms, i.e., the firms purposely experimenting to learn more about demand and the extent that local demographics and competition can affect the experimentation and whether there are spill-overs from local competition (i.e. do firms learn from each other and does this effect how much they experiment and how quickly they learn).
My main findings are that over time, firms within this market have learned better how to price discriminate over the holiday season; firms experiment more with prices for the pint sized products than the larger sizes; and that menu of options that firms have offered has been expanding but at a slower rate, suggesting that they are approaching a long-run steady state for the optimal menu of options.
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Maritime Engineering Risk Assessment by Integrating Interpretive Structural Modeling and Bayesian Network, a Case Study of Offshore PipingWu, Wei-Shing 05 September 2011 (has links)
Taiwan, as an island country, should place future aspiration on the usages of ocean energy and marine resources, such as offshore wind power and deep ocean water. The sound development of marine services relies on a strong industry of maritime engineering. The perilous marine environment has posed the highest risk for all maritime civil engineering activities. It is therefore imperative to restrain the risk associated with current maritime work, other than just engineering technique itself. By doing so, the quality of maritime work can be assured, and as the improvement of overall engineering capability, Taiwan can compete worldwide in the maritime engineering industry.
Maritime works have developed their own standard construction procedures. To mitigate risk of maritime works depend mainly on the domain experts¡¦ experience and know-how. However, problems appear when less experienced experts are available, or qualitative experience exists in a narrative form. It is therefore important to structure clearly an engineering risk factor relation, and quantify and control these risk factors. The proposed study will first collect and review related literatures, and then interview an expert from the designate maritime service company to establish the risk factors associated with offshore piping. Eventually a complete Bayesian network (BN) was formulated based on the cause-effect diagram, using Interpretive Structural Modeling (ISM), and experts¡¦ experience was transformed into a set of prior and conditional probability to be embedded in the BN. The BN can clearly show that certain earlier operational factors affect final operational process deeply. Besides, the backward reasoning using the BN is possible to identify the factors causing a project failure.
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An Appraisal Of Curvilinear Forms In Architecture With An Emphasis On Structural Behaviour: A Case Study On Channel Tunnel Railway Terminal At WaterlooCingi, Tuba 01 January 2007 (has links) (PDF)
Architectural curvilinear form has been on the scene since the time of the first building shelters. Curve is the most common form in nature. This phenomenon inspired human beings while they are building structures. Curvilinear form has developed over centuries, via structural enhancements and aesthetic tenets. A symbolic meaning is tailored to curvilinear structures such as use of domes in religious buildings. However, the difficulties in the construction process of these forms have been a challenge for people throughout the history. Today, introduction of computer aided design and manufacturing technologies into building industry encourages the use of curvilinear forms in architecture. This study intends to explore the relationship between structure and architectural curvilinear form. The curvilinear form will be examined basically according to its structural potentials through its geometrical configuration. A computer model of the roof of Channel Tunnel Railway Terminal at Waterloo is generated and with some geometrical modifications for the configuration of the roof, new schemes of structures are obtained. An analytical comparison of structural behavior and efficiency is made via the computer model of the roof and these modified configurations.
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Three essays on adoption in social networksShi, Zhan 22 February 2013 (has links)
In the fast growing online social networks, one of the most commonly observed phenomena is the diffusion of information contents, behaviors or products through network members’ interactions. In this thesis, I study the diffusion phenomenon by examining the individual-level adoption decision, both theoretically and empirically. In the three essays, I study the effects of the strength of the interpersonal tie and the social network characteristics on a potential adopter’s decision-making, and investigate the measurement of network members’ influences. / text
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Vyriškų transformuojamų kelnių projektavimo ypatumai / The peculiarities of designing men transformable trousersŽukauskaitė, Živilė 02 July 2012 (has links)
Transformuojamų drabužių apžvalgoje nagrinėjami jų tikslai, kryptys ir drabužių detalių laikino tipo jungimo priemonės. Pateikiamas gaminio aprašymas ir jo techninis piešinys. Gaminiui parenkamas audinys ir tinkama furnitūra. Nurodomi reikalavimai gaminio priežiūrai. Apibūdinama pasirinkta vyriškų transformuojamų kelnių bazinės konstrukcijos projektavimo metodika, atliekamas konstrukcinis modeliavimas. Nubraižomi lekalai, atliekamas, gaminio lekalų dauginimas pagal dydžius. Sudaroma išklotinė ir paskaičiuojamos tarplekalinės sąnaudos. Apibūdinama atliekama gaminio kokybės kontrolė. / The review of transformable trousers analyzes their aims, trends and means of temporary type of connection for parts of clothing. The product description and technical drawing is also provided in this part. Fabric and appropriate fittings are selected for the product. It also gives the requirements for product’s maintenance. A description is given of the selected transformable men's trousers basic structural design methodology; a structural modeling is carried out. The thesis gives the drawings of molds, the propagation of product’s molds according to its sizes. It also provides the development and the evaluation of material remains’ costs. A description of the product quality control is performed.
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