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Using Three Different Categorical Data Analysis Techniques to Detect Differential Item FunctioningStephens-Bonty, Torie Amelia 16 May 2008 (has links)
Diversity in the population along with the diversity of testing usage has resulted in smaller identified groups of test takers. In addition, computer adaptive testing sometimes results in a relatively small number of items being used for a particular assessment. The need and use for statistical techniques that are able to effectively detect differential item functioning (DIF) when the population is small and or the assessment is short is necessary. Identification of empirically biased items is a crucial step in creating equitable and construct-valid assessments. Parshall and Miller (1995) compared the conventional asymptotic Mantel-Haenszel (MH) with the exact test (ET) for the detection of DIF with small sample sizes. Several studies have since compared the performance of MH to logistic regression (LR) under a variety of conditions. Both Swaminathan and Rogers (1990), and Hildalgo and López-Pina (2004) demonstrated that MH and LR were comparable in their detection of items with DIF. This study followed by comparing the performance of the MH, the ET, and LR performance when both the sample size is small and test length is short. The purpose of this Monte Carlo simulation study was to expand on the research done by Parshall and Miller (1995) by examining power and power with effect size measures for each of the three DIF detection procedures. The following variables were manipulated in this study: focal group sample size, percent of items with DIF, and magnitude of DIF. For each condition, a small reference group size of 200 was utilized as well as a short, 10-item test. The results demonstrated that in general, LR was slightly more powerful in detecting items with DIF. In most conditions, however, power was well below the acceptable rate of 80%. As the size of the focal group and the magnitude of DIF increased, the three procedures were more likely to reach acceptable power. Also, all three procedures demonstrated the highest power for the most discriminating item. Collectively, the results from this research provide information in the area of small sample size and DIF detection.
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"Clustering Categorical Response" Application to Lung Cancer Problems in Living ScalesGuo, Ling 22 April 2008 (has links)
The study aims to estimate the ability of different grouping techniques on categorical response. We try to find out how well do they work? Do they really find clusters when clusters exist? We use Cancer Problems in Living Scales from the ACS as our categorical data variables and lung cancer survivors as our studying group. Five methods of cluster analysis are examined for their accuracy in clustering on both real CPILS dataset and simulated data. The methods include hierarchical cluster analysis (Ward's method), model-based clustering of raw data, model-based clustering of the factors scores from a maximum likelihood factor analysis, model-based clustering of the predicted scores from independent factor analysis, and the method of latent class clustering. The results from each of the five methods are then compared to actual classifications. The performance of model-based clustering on raw data is poorer than that of the other methods and the latent class clustering method is most appropriate for the specific categorical data examined. These results are discussed and recommendations are made regarding future directions for cluster analysis research.
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カテゴリカル・データの非計量的主成分分析の応用村上, 隆, Murakami, Takashi 26 December 1997 (has links)
国立情報学研究所で電子化したコンテンツを使用している。
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KJ法および多重対応分析を用いた自由記述型応答の数量化鈴木, 郁子, SUZUKI, Ikuko, 和田, 真雄, WADA, Shinyu, 村上, 隆, MURAKAMI, Takashi 27 December 2005 (has links)
国立情報学研究所で電子化したコンテンツを使用している。
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Algorithmically Guided Information Visualization : Explorative Approaches for High Dimensional, Mixed and Categorical Data / Algoritmiskt vägledd informationsvisualisering för högdimensionell och kategorisk dataJohansson Fernstad, Sara January 2011 (has links)
Facilitated by the technological advances of the last decades, increasing amounts of complex data are being collected within fields such as biology, chemistry and social sciences. The major challenge today is not to gather data, but to extract useful information and gain insights from it. Information visualization provides methods for visual analysis of complex data but, as the amounts of gathered data increase, the challenges of visual analysis become more complex. This thesis presents work utilizing algorithmically extracted patterns as guidance during interactive data exploration processes, employing information visualization techniques. It provides efficient analysis by taking advantage of fast pattern identification techniques as well as making use of the domain expertise of the analyst. In particular, the presented research is concerned with the issues of analysing categorical data, where the values are names without any inherent order or distance; mixed data, including a combination of categorical and numerical data; and high dimensional data, including hundreds or even thousands of variables. The contributions of the thesis include a quantification method, assigning numerical values to categorical data, which utilizes an automated method to define category similarities based on underlying data structures, and integrates relationships within numerical variables into the quantification when dealing with mixed data sets. The quantification is incorporated in an interactive analysis pipeline where it provides suggestions for numerical representations, which may interactively be adjusted by the analyst. The interactive quantification enables exploration using commonly available visualization methods for numerical data. Within the context of categorical data analysis, this thesis also contributes the first user study evaluating the performance of what are currently the two main visualization approaches for categorical data analysis. Furthermore, this thesis contributes two dimensionality reduction approaches, which aim at preserving structure while reducing dimensionality, and provide flexible and user-controlled dimensionality reduction. Through algorithmic quality metric analysis, where each metric represents a structure of interest, potentially interesting variables are extracted from the high dimensional data. The automatically identified structures are visually displayed, using various visualization methods, and act as guidance in the selection of interesting variable subsets for further analysis. The visual representations furthermore provide overview of structures within the high dimensional data set and may, through this, aid in focusing subsequent analysis, as well as enabling interactive exploration of the full high dimensional data set and selected variable subsets. The thesis also contributes the application of algorithmically guided approaches for high dimensional data exploration in the rapidly growing field of microbiology, through the design and development of a quality-guided interactive system in collaboration with microbiologists.
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Categorical quantum dynamicsGogioso, Stefano January 2016 (has links)
Since their original introduction, strongly complementary observables have been a fundamental ingredient of the ZX calculus, one of the most successful fragments of Categorical Quantum Mechanics (CQM). In this thesis, we show that strong complementarity plays a vastly greater role in quantum theory. Firstly, we use strong complementarity to introduce dynamics and symmetries within the framework of CQM, which we also extend to infinite-dimensional separable Hilbert spaces: these were long-missing features, which open the way to a wealth of new applications. The coherent treatment presented in this work also provides a variety of novel insights into the dynamics and symmetries of quantum systems: examples include the extremely simple characterisation of symmetry-observable duality, the connection of strong complementarity with the Weyl Canonical Commutation Relations, the generalisations of Feynman's clock construction, the existence of time observables and the emergence of quantum clocks. Secondly, we show that strong complementarity is a key resource for quantum algorithms and protocols. We provide the first fully diagrammatic, theory-independent proof of correctness for the quantum algorithm solving the Hidden Subgroup Problem, and show that strong complementarity is the feature providing the quantum advantage. In quantum foundations, we use strong complementarity to derive the exact conditions relating non-locality to the structure of phase groups, within the context of Mermin-type non-locality arguments. Our non-locality results find further application to quantum cryptography, where we use them to define a quantum-classical secret sharing scheme with provable device-independent security guarantees. All in all, we argue that strong complementarity is a truly powerful and versatile building block for quantum theory and its applications, and one that should draw a lot more attention in the future.
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Completeness and the ZX-calculusBackens, Miriam K. January 2015 (has links)
Graphical languages offer intuitive and rigorous formalisms for quantum physics. They can be used to simplify expressions, derive equalities, and do computations. Yet in order to replace conventional formalisms, rigour alone is not sufficient: the new formalisms also need to have equivalent deductive power. This requirement is captured by the property of completeness, which means that any equality that can be derived using some standard formalism can also be derived graphically. In this thesis, I consider the ZX-calculus, a graphical language for pure state qubit quantum mechanics. I show that it is complete for pure state stabilizer quantum mechanics, so any problem within this fragment of quantum theory can be fully analysed using graphical methods. This includes questions of central importance in areas such as error-correcting codes or measurement-based quantum computation. Furthermore, I show that the ZX-calculus is complete for the single-qubit Clifford+T group, which is approximately universal: any single-qubit unitary can be approximated to arbitrary accuracy using only Clifford gates and the T-gate. In experimental realisations of quantum computers, operations have to be approximated using some such finite gate set. Therefore this result implies that a wide range of realistic scenarios in quantum computation can be analysed graphically without loss of deductive power. Lastly, I extend the use of rigorous graphical languages outside quantum theory to Spekkens' toy theory, a local hidden variable model that nevertheless exhibits some features commonly associated with quantum mechanics. The toy theory for the simplest possible underlying system closely resembles stabilizer quantum mechanics, which is non-local; it thus offers insights into the similarities and differences between classical and quantum theories. I develop a graphical calculus similar to the ZX-calculus that fully describes Spekkens' toy theory, and show that it is complete. Hence, stabilizer quantum mechanics and Spekkens' toy theory can be fully analysed and compared using graphical formalisms. Intuitive graphical languages can replace conventional formalisms for the analysis of many questions in quantum computation and foundations without loss of mathematical rigour or deductive power.
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Incorporating Interactions and Gene Annotation Data in Genomic PredictionMartini, Johannes Wolfgang Robert 03 November 2017 (has links)
No description available.
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Influence de la surdité neurosensorielle sur la perception de la hauteur tonale / Influence of neurosensory hearing loss on perception of pitchColin, David 12 December 2016 (has links)
Dans le cas de perte auditive neurosensorielle, la biomécanique cochléaire se trouve modifiée et les phénomènes actifs liés aux cellules ciliées sont altérés. Si les conséquences sur la baisse de sensibilité, les capacités de sélectivité fréquentielle ou la compréhension de la parole dans le bruit sont bien connus, la perception de la hauteur tonale peut également être modifiée suite à une perte neurosensorielle. Cette thèse se propose d’étudier la perception de la hauteur à travers quatre approches chez des sujets présentant une surdité neurosensorielle. La première étude s’intéresse à la diplacousie et a montré que ce phénomène était bien plus fréquent que ce que l’on pouvait imaginer. Les résultats ont montré que la perception était en règle générale plus aiguë sur l’oreille la plus lésée. La seconde étude propose une mesure catégorielle de la tonie. Les résultats ont montré que pour une même fréquence, les malentendants percevaient un son comme plus aigu que les normo-entendants. La troisième étude traite de la correspondance d’octave et de l’écoute de la musique. Les résultats montrent que la perte auditive est corrélée avec la perception de l’octave. La quatrième étude s’intéresse à la perception catégorielle des fricatives non-voisées. Les résultats montrent que la frontière catégorielle est décalée vers les fréquences graves ce qui semble être le reflet d’une perception plus aigue de ces phonèmes. Ces résultats d’expériences de psychoacoustique vont dans le sens des études menées sur des animaux montrant une modification de la carte tonotopique cochléaire et des fréquences caractéristiques des neurones lors d’une atteinte neurosensorielle. Ces observations pourraient conduire à une meilleure prise en charge des malentendants et à l’élaboration de nouveaux algorithmes sur les futures aides auditives / In the case of sensorineural hearing loss, the cochlear mechanism is modified and the active phenomena linked to the hair cells are altered. If the effects on decreased sensitivity, frequency selectivity, or speech in noise intelligibility are well known, the perception of pitch can also be altered following a neurosensory hearing loss. This thesis proposes to study the perception of pitch with four approaches in subjects with neurosensory hearing loss. The first study focuses on diplacusis and has shown that this phenomenon is much more frequent than one could imagine. The results showed that perception was generally higher on the worse ear. The second study proposes a categorical measure of pitch. The results showed that for the same frequency, the hearing-impaired perceived a sound higher than the normal hearing listeners. The third study is about octave matching and listening to music. The results show that hearing loss correlates with the octave matching frequency. The fourth study focuses on the categorical perception of voiceless fricatives. The results show that the categorical boundary is shifted towards the low frequencies, which seems to reflect a higher perception of these phonemes. These results of psychoacoustic experiments are consistent with the studies carried out on animals showing a modification of the cochlear tonotopic map and the characteristic frequencies of the neurons in case of a neurosensory hearing loss. These observations could lead to better care for the hearing impaired and to the development of new algorithms on future hearing aids
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Kant e o problema da liberdade na fundamentação da metafísica dos costumes / The problem of freedom in Kant's Groundwork of the Metaphysics of MoralsSantos, Rogério do Amaral [UNIFESP] 30 November 2014 (has links) (PDF)
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Previous issue date: 2014-11-25 / A partir da consciência do dever, a liberdade humana deve ser entendida, segundo
Kant, como condição e fundamento da lei moral. De que modo conciliar, entretanto, a
liberdade das ações com a obediência a uma lei? A fim de responder a essa questão, trata-se
de distinguir os conceitos kantianos de "liberdade transcendental", "liberdade prática" e
"autonomia". Em linhas gerais, a liberdade transcendental depende da solução da Crítica da
razão pura à terceira antinomia, operada pela distinção fenômeno/coisa em si, que torna as
afirmações sobre a necessidade da natureza e sobre a liberdade da vontade proposições não
contraditórias. Por sua vez, a liberdade prática, ainda de acordo com a primeira Crítica,
designa aquilo que comumente se entende por livre-arbítrio, pressuposto da responsabilidade
moral dos agentes. Quanto ao conceito kantiano de autonomia, ele é tematizado
explicitamente, pela primeira vez, na Fundamentação da metafísica dos costumes, e
apresenta-se como a terceira dentre as fórmulas principais do imperativo categórico, aquela
que ―unifica em si as outras duas‖, isto é, as fórmulas da lei universal e da humanidade.
Repensar, a partir de Kant, uma ética do dever, diferentemente de uma ética da virtude, e o
problema da liberdade humana exige o estudo desses dois textos, escolhidos como etapas
obrigatórias para quaisquer tentativas de reelaboração dessas questões tradicionais em termos
contemporâneos. / According to Kant, human freedom is the ground of moral law. In what sense, however,
freedom of action agrees with obedience to law? To answer this question it is necessary to
distinguish Kant's concepts of "transcendental freedom", "practical freedom" and "autonomy".
In the Critique of Pure Reason, transcendental freedom depends on the solution of the third
antinomy. The thesis on the freedom of the will and the antithesis on the necessity of nature
can be considered as non-contradictory statements by means of the distinction between
phenomenon and noumenon. Still according to the first Critique, practical freedom refers to
what is commonly meant by free choice, and concerns to the moral responsibility of agents.
Finally, as to the Kantian concept of autonomy, it is subject of the Groundwork of the
Metaphysics of Morals. It consists of the third among the three main formulas of the
categorical imperative, and "unites in itself the other two", the formula of universal law and
the formula of humanity. Any attempt to understand, in contemporary terms, the problem of
human freedom as well as an ethics of duty require the analysis of these Kantian concepts.
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