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Full-Text Articles in Physical Sciences and Mathematics

Many-Objective Evolutionary Algorithms: Objective Reduction, Decomposition And Multi-Modality., Monalisa Pal Dr. Jan 2022

Many-Objective Evolutionary Algorithms: Objective Reduction, Decomposition And Multi-Modality., Monalisa Pal Dr.

Doctoral Theses

Evolutionary Algorithms (EAs) for Many-Objective Optimization (MaOO) problems are challenging in nature due to the requirement of large population size, difficulty in maintaining the selection pressure towards global optima and inability of accurate visualization of high-dimensional Pareto-optimal Set (in decision space) and Pareto-Front (in objective space). The quality of the estimated set of Pareto-optimal solutions, resulting from the EAs for MaOO problems, is assessed in terms of proximity to the true surface (convergence) and uniformity and coverage of the estimated set over the true surface (diversity). With more number of objectives, the challenges become more profound. Thus, better strategies have …


Mathematical Formulations For Complex Resource Scheduling Problems., T. R. Lalita Dr. Jan 2022

Mathematical Formulations For Complex Resource Scheduling Problems., T. R. Lalita Dr.

Doctoral Theses

This thesis deals with development of effective models for large scale real-world resource scheduling problems. Efficient utilization of resources is crucial for any organization or industry as resources are often scarce. Scheduling them in an optimal way can not only take care of the scarcity but has potential economic benefits. Optimal utilization of resources reduces costs and thereby provides a competitive edge in the business world. Resources can be of different types such as human (personnel-skilled and unskilled), financial(budgets), materials, infrastructures(airports and seaports with designed facilities, windmills, warehouses’ area, hotel rooms etc) and equipment (microprocessors, cranes, machinery, aircraft simulators for …


A Brief Treatise On Bayesian Inverse Regression., Debashis Chatterjee Dr. Dec 2021

A Brief Treatise On Bayesian Inverse Regression., Debashis Chatterjee Dr.

Doctoral Theses

Inverse problems, where in a broad sense the task is to learn from the noisy response about some unknown function, usually represented as the argument of some known functional form, has received wide attention in the general scientific disciplines. However, apart from the class of traditional inverse problems, there exists another class of inverse problems, which qualify as more authentic class of inverse problems, but unfortunately did not receive as much attention.In a nutshell, the other class of inverse problems can be described as the problem of predicting the covariates corresponding to given responses and the rest of the data. …


Some Nonparametric Hybrid Predictive Models : Asymptotic Properties And Applications., Tanujit Chakraborty Dr. Nov 2021

Some Nonparametric Hybrid Predictive Models : Asymptotic Properties And Applications., Tanujit Chakraborty Dr.

Doctoral Theses

Prediction problems like classification, regression, and time series forecasting have always attracted both the statisticians and computer scientists worldwide to take up the challenges of data science and implementation of complicated models using modern computing facilities. But most traditional statistical and machine learning models assume the available data to be well-behaved in terms of the presence of a full set of essential features, equal size of classes, and stationary data structures in all data instances, etc. Practical data sets from the domain of business analytics, process and quality control, software reliability, and macroeconomics, to name a few, suffer from various …


On Tests Of Independence Among Multiplerandom Vectors Of Arbitrary Dimensions., Angshuman Roy Dr. Apr 2021

On Tests Of Independence Among Multiplerandom Vectors Of Arbitrary Dimensions., Angshuman Roy Dr.

Doctoral Theses

Measures of dependence among several random vectors and associated tests of independence play a major role in different statistical applications. Blind source separation or independent component analysis (see, e.g., Hyv¨arinen et al., 2001; Shen et al., 2009), feature selection and feature extraction (see, e.g., Li et al., 2012), detection of serial correlation in time series (see, e.g., Ghoudi et al., 2001) and finding the causal relationships among the variables (see, e.g., Chakraborty and Zhang, 2019) are some examples of their wide-spread applications. Tests of independence has vast applications in other areas of sciences as well. For instance, to characterize the …


Essays In Social Choice Theory., Dipjyoti Majumdar Dr. Feb 2021

Essays In Social Choice Theory., Dipjyoti Majumdar Dr.

Doctoral Theses

The purpose of this thesis is to explore some issues in social choice theory and decision theory. Social choice theory provides the theoretical foundations for the field of public choice and welfare economics. It tries to bring together normative aspects like perspective value judgements and positive aspects, like strategic con- siderations. The second feature which is our focus, is closely related to the problem of providing appropriate incentives to agents, an issue of prime importance in eco- nomics.Consider for example, a set of agents who must elect one among a set of can- didates. These candidates may be physical agents …


Mechanism Design For Land Acquisition., Soumendu Sarkar Dr. Sep 2016

Mechanism Design For Land Acquisition., Soumendu Sarkar Dr.

Doctoral Theses

Conversion of land use from agriculture to industry is a typical feature of economic development in many densely populated countries. Large scale construction often requires industry or the government to acquire vast areas of land that are inhabited and often cultivated, by hundreds and even thousands of people. For some landowners, possession signifies power and status in society, while for others, it is the only means for earning a livelihood.Adamopoulos and Restuccia (2014) use data from World Census of Agriculture to show that average farm size in the poorest 20% of countries is 1.6 hectares, while that in the richest …


Inference On Time-To-Event Distribution From Retrospective Data With Imperfect Recall., Sedigheh Salehabadi Dr. Mar 2016

Inference On Time-To-Event Distribution From Retrospective Data With Imperfect Recall., Sedigheh Salehabadi Dr.

Doctoral Theses

Time-to-event data arises from measurements of time till the occurrence of an event of interest. Such data are common in the fields of biology, epidemiology, pub- lic health, medical research, economics and industry. The event of interest can be the death of a human being (Klein and Moeschberger, 2003), failure of a machine (Zhiguo et al., 2007), onset of menarche in adolescent and young adult females (Bergsten-Brucefors, 1976; Chumlea et al., 2003; Mirzaei, Sengupta and Das, 2015), onset (or relapse) of a disease (Klein and Moeschberger, 2003), dental develop- ment (Demirjian, Goldstien and Tanner, 1973; Eveleth and Tanner, 1990), breast …


Some Distribution-Free Two-Sample Tests Applicable To High Dimension, Low Sample Size Data., Munmun Biswas Dr. Feb 2016

Some Distribution-Free Two-Sample Tests Applicable To High Dimension, Low Sample Size Data., Munmun Biswas Dr.

Doctoral Theses

The advancement of data acquisition technologies and computing resources have greatly facilitated the analysis of massive data sets in various fields of sciences. Researchers from different disciplines rigorously investigate these data sets to extract useful information for new scientific discoveries. Many of these data sets contain large number of features but small number of observations. For instance, in the fields of chemometrics (see e.g., Schoonover et al. (2003)), medical image analysis (see e.g., Yushkevich et al. (2001)) and microarray gene expression data analysis (see e.g., Eisen and Brown (1999), Alter et al. (2000)), we often deal with data of dimensions …


Nonparametric Methods For Data In Infinite Dimensional Space., Anirvan Chakraborty Dr. Dec 2015

Nonparametric Methods For Data In Infinite Dimensional Space., Anirvan Chakraborty Dr.

Doctoral Theses

For univariate as well as finite dimensional multivariate data, there is an extensive literature on nonparametric statistical methods. One of the reasons for the popularity of nonparametric methods is that it is often difficult to justify the assumptions (e.g., Gaussian distribution of the data) made in the models used in parametric methods. Nonparametric procedures use more flexible models, which involve less assumptions. So, they are more robust against possible departures from the model assumptions, and are applicable to a wide variety of data. Nonparametric methods outperform their parametric competitors in many situations, where the assumptions required for the parametric methods …


Essays In Political Economy And Voting., Mihir Bhattacharya Dr. Oct 2015

Essays In Political Economy And Voting., Mihir Bhattacharya Dr.

Doctoral Theses

This thesis comprises three chapters on issues in political economy and voting. The first chapter considers a multilevel multidimensional aggregation problem in voting. The second chapter considers a model of party formation where citizens propose links to other candidates. The final chapter considers a model of electoral competition between regional and national parties.We provide a brief description of each chapter below. 1.1 Multilevel Multidimensional Consistent AggregatorsIn this chapter we study gerrymander-proof or consistent aggregation rules in different contexts. There are several papers that have studied the structure of consistent voting rules satisfying various versions of consistency. Virtually all these papers …


On The Analysis Of Some Recursive Equations In Probability., Arunangshu Biswas Dr. Sep 2015

On The Analysis Of Some Recursive Equations In Probability., Arunangshu Biswas Dr.

Doctoral Theses

This thesis deals with recursive systems used in theoretical and applied probability. Recursive systems are stochastic processes {Xn}n≥1 where the Xn depends on the earlier Xn−1 and also on some increment process which is uncorrelated with the process Xn. The simplest example of a recursive system is the Random Walk, whose properties have been extensively studied. Mathematically a recursive system takes the form Xn = f(Xn−1, n), is the increment/ innovation procedure and f(·, ·) is a function on the product space of xn and n. We first consider a recursive system called Self-Normalized sums (SNS) corresponding to a sequence …


On Supervised And Unsupervised Methodologies For Mining Of Text Data., Tanmay Basu Dr. Jul 2015

On Supervised And Unsupervised Methodologies For Mining Of Text Data., Tanmay Basu Dr.

Doctoral Theses

The supervised and unsupervised methodologies of text mining using the plain text data of English language have been discussed. Some new supervised and unsupervised methodologies have been developed for effective mining of the text data after successfully overcoming some limitations of the existing techniques.The problems of unsupervised techniques of text mining, i.e., document clustering methods are addressed. A new similarity measure between documents has been designed to improve the accuracy of measuring the content similarity between documents. Further, a hierarchical document clustering technique is designed using this similarity measure. The main significance of the clustering algorithm is that the number …


Complete And Partial Ordering Approaches In The Context Of Poverty Ordering And On The Impacts Of Growth And Inequality On Poverty., Sandip Sarkar Dr. Jul 2015

Complete And Partial Ordering Approaches In The Context Of Poverty Ordering And On The Impacts Of Growth And Inequality On Poverty., Sandip Sarkar Dr.

Doctoral Theses

No abstract provided.


Essays On Incentive Compatibility On Restricted Domains., Anup Pramanik Dr. Jun 2015

Essays On Incentive Compatibility On Restricted Domains., Anup Pramanik Dr.

Doctoral Theses

This thesis comprises three chapters that investigate the structure of dominant strategy incentive compatible (strategy-proof) social choice functions on restricted domains. The first chapter deals with standard mechanism design problem in quasi-linear environments with multidimensional non-convex type spaces. It identifies a class of type spaces called ordinal type spaces and shows that the simple and familiar 2-cycle monotonicity condition is necessary and sufficient for implementation. This result covers the single-peaked domain. The second chapter deals with the standard social choice problem (no monetary transfers) but one where agents have indifference in their preference orderings generated via an exogenous partition of …


Some Studies On Selected Stream Ciphers Analysis Fault Attack & Related Results., Subhadeep Banik Dr. May 2015

Some Studies On Selected Stream Ciphers Analysis Fault Attack & Related Results., Subhadeep Banik Dr.

Doctoral Theses

Stream Ciphers are important Symmetric Cryptological primitives, built for the purpose of providing secure message encryption. As no formal security proofs exist, our confidence in these algorithms is largely based on the fact that intense cryptanalysis has been carried out over several years without revealing any weakness. This thesis makes some independent contributions to the cryptanalysis of a selection of stream ciphers.In this thesis, we take a closer look at two stream ciphers viz. RC4+ designed by Maitra et al. at Indocrypt 2008 and GGHN designed by Gong et al. at CISC 2005. Both these ciphers were designed as viable …


Modelling Stock Returns In 'Volatility-In-Mean' Framework Under Up And Down Market Movements, Srikanta Kundu Dr. Jul 2014

Modelling Stock Returns In 'Volatility-In-Mean' Framework Under Up And Down Market Movements, Srikanta Kundu Dr.

Doctoral Theses

The first chapter of this thesis begins with a brief review of the existing literature on empirical studies on stock returns, especially those in the context of the relationship between risk and return, at both univariate and multivariate levels. In the next section, studies on the relationship between stock return and monetary policy are reviewed. The motivation of this work is discussed in Section 1.4. Finally, the format of the thesis is given in Section 1.5.A Brief Review of the Literature on Risk-Return Relationship-Both Univariate and Multivariate Cases. In this section, we first present a brief review of this literature …


Sampling 'Survey Populations': Some Problems And Their Solutions., Kajal Dihidar Dr. Feb 2011

Sampling 'Survey Populations': Some Problems And Their Solutions., Kajal Dihidar Dr.

Doctoral Theses

In this thesis we study some problems in survey sampling and propose their solutions. The thesis is divided into seven chapters, the first being an introductory one. Chapters 2-4 relate to surveys with direct responses, while Chapters 5-7 deal with randomized responses. We begin by introducing the motivations behind the principal problems studied in this thesis.The first problem arose while developing a survey where the objective was to estimate the tot al number of workers in different industries in the rural unorganized sector in a district of the state of West Bengal, India. For this, the technique of adaptive sampling …


Order-Restricted Covariate Effects And Hazard Regression Models., Arnab Bhattacharjee Dr. Feb 2009

Order-Restricted Covariate Effects And Hazard Regression Models., Arnab Bhattacharjee Dr.

Doctoral Theses

The proportional hazards (PH) model, but more speciÖcally its special case the Cox regression model (Cox, 1972), plays an important role in the theory and practice of lifetime and duration data analysis. This is because the PH model (and the Cox regression model) provides a convenient way to evaluate the ináuence of one or several covariates on the probability of conclusion of lifetime or duration spells. However, the PH speciÖcation substantially restricts interdependence between the explanatory variables and the lifetime in determining the hazard. In particular, the Cox regression model model restricts the coe¢ cients of the regressors in the …


Predictability In The Indian Stock Market: A Study From An Econometric Perspective., Debabrata Mukhopadhyay Dr. Dec 2008

Predictability In The Indian Stock Market: A Study From An Econometric Perspective., Debabrata Mukhopadhyay Dr.

Doctoral Theses

No abstract provided.


Multiattribute Acceptance Sampling Plans., Anup Majumdar Dr. Sep 2006

Multiattribute Acceptance Sampling Plans., Anup Majumdar Dr.

Doctoral Theses

Irrespective of the type of product, evaluation of conformity to specified requirements of its quality characteristics is an integral part of quality assurance. Although they form a set of necessary verification activities almost at all stages of production, these activities, known as inspection do not add value to the product on their own and are to be kept at their minimum. The sampling inspection where a portion of a collection of product units is inspected on a set of characteristics with a view to making decision about acceptance or otherwise becomes relevant in this context.The number of elements of the …


Some Nonparametric And Semiparametric Methods For Discriminant Analysis., Anil Kumar Ghosh Dr. Apr 2005

Some Nonparametric And Semiparametric Methods For Discriminant Analysis., Anil Kumar Ghosh Dr.

Doctoral Theses

Discriminant analysis (see e.g., Devijver and Kittler, 1982; Duda, Hart and Stork, 2000; Hastle, Tibahirani and Friedman, 2001) deals with the separation of different groups of obaervationa and allocation of a new oboervation to one of the previously delined grouga. In a J-class discriminant analysis problem, we usually hae a training sample of the form {(xk, ck) : k = 1,2,...,N}, where xk = (Ik1,Ik2,...J) is a d-dimensional measarement vector, and ca € {1,2,...,J} is its class label. On the basis of thia training sample, one aims to form a decision rule d(x) : Rd + (1,2,...,J} for clasifying the …


Some Contributions To Semidefine Linear Complementary Problem., D. Sampangi Raman Dr. Feb 2005

Some Contributions To Semidefine Linear Complementary Problem., D. Sampangi Raman Dr.

Doctoral Theses

This thesis is composed of chapters 1 to 5. In Chapter 1, we formally define SDLCP and give some examples of SDLCP and show that SDLCP is a special case of variational inequality problem. Also we show that LCP is indeed a special case of SDLCP. Later section of this chapter deals with definitions and notations.In Chapter 2, we are concerned with the results which have been obtained in an effort to generalize the P-matrix condition of LCP to SDLCP. It is known that a matrix M is a P-matrix if and only if M does not re verse the …


Essays On Dynamic Disequilibrium Models., Arpita Dhar Dr. Jan 2005

Essays On Dynamic Disequilibrium Models., Arpita Dhar Dr.

Doctoral Theses

The present dissertation is devoted to the analysis of some problems of economic growth in the framework of what has been called Disequilibrium model.Studies on economic growth have been mostly confined, with few exceptions, to the analysis of equilibrium models. But in reality there are cases where the concept of equilibrium may not be relevant and hence a disequilibrium approach is needed. The present thesis is concerned with analysing some theoretical and empirical aspects of the problem of economic growth in a disequilibrium framework. At the theoretical level, the objective has been to re-examine the conclusions of some existing equilibrium …


Contributions To Emerging Techniques In Survey Sampling., Sanghamitra Pal Dr. Jun 2004

Contributions To Emerging Techniques In Survey Sampling., Sanghamitra Pal Dr.

Doctoral Theses

This dissertation contains seven Chapters. The contents in the respective Chapters may be briefly recounted as follows.A topic of classical interest in survey sampling is how to ensure the existence of a uniformly non-negative (UNN) unbiased estimator for the mean square error (MSE) of a homogeneous linear estimator (HLE) for a finite survey population total. Hájek (1958), Vijayan (1975), Rao and Vijayan (1977) and Rao (1979) developed a number of results which boil down to the folowing as narrated in the monograph by Chaudhuri and Stenger (1992).If there exist non-zero constants w, and the unknown values y, of the variable …


Some Issues On Time Varying Risk Premium In Arch-M Model., Samarjit Das Dr. Jun 2003

Some Issues On Time Varying Risk Premium In Arch-M Model., Samarjit Das Dr.

Doctoral Theses

Since the 1970's it has been observed in many economies that financial and macroeconomic variables like equity prices, treasury bill rates and exchange rates have become more and more volatile in nature. This may be due tumor flexible monetary policies pursued in these countries as well as due to their increasing exposure towards various international developments. Accordingly, economic agents are facing increasingly more and more risky environment. Re- searchers as well as professional economists in the area of capital and business finance have, therefore, been increasingly attracted in recent years towards studying the effect of risk and uncertainty on asset …


Slippage And Change Point Problem With Directional Data., Arnab Kumar Laha Dr. May 2002

Slippage And Change Point Problem With Directional Data., Arnab Kumar Laha Dr.

Doctoral Theses

In this thesis we develop statistical methods for dealing with two problems namely (1) THE SLIPPAGE PROBLEM and (2) THE CHANGE POINT PROB- LEM in the set-up of directional data. In this chapter, we provide an intro- duction to these problems and discuss the importance of the present work. The slippage problem is basically a problem to detect whether any unspecified observation in a given random sample comes from a distribution different from that for all the other remaining observations. This can also be viewed as a problem of outlier detection or that of spuriosity. This problem assumes great importance …


Essays In Indian Corporate Finance., K. V. S. Vinay Dr. Apr 2002

Essays In Indian Corporate Finance., K. V. S. Vinay Dr.

Doctoral Theses

This thesis comprises of three essays in corporate finance focusing on the Indian economy. The first essay contains a theoretical model while the second and the third essays are empirical exercises. In the subsequent paragraphs of this section, we examine the broader issues to which the contents of the thesis contribute.The past few years have seen rising interest in studies of financial insti- tutions and corporate financial policies in countries other than the United States. One of the reasons for such a shift in attention is the diversity in the size and structure of financial arrangements all over the world. …


On Some Optimal Tests In Finite Mixtures: Constructions And Applications., Chandranath Pal Dr. Nov 2001

On Some Optimal Tests In Finite Mixtures: Constructions And Applications., Chandranath Pal Dr.

Doctoral Theses

Mixtures of distributions are now-a-days playing very important roles in both theoretical and applied statistics. There is an abundance of real-life situations where mixture distributions are being extensively used for modelling data and drawing inference. Several books and monographs on mixtures have so far been published, e.g., Everitt and Hand (1981), Titterington et al. (1985), McLachlan and Basford (1988), McLachlan (1997) etc., which cover a wide area on different aspects of mixture distributions and their applications. The book by Titterington et al. (1985, pp. 16-21), in particular, contains a comprehensive list of references on direct applications of finite mixtures in …


Stochastic Comparision And Dependence Among Order Statistics,Spacing And Concomitants Of Order Statistics., Baha-Eldin Khaledi Dr. Mar 2001

Stochastic Comparision And Dependence Among Order Statistics,Spacing And Concomitants Of Order Statistics., Baha-Eldin Khaledi Dr.

Doctoral Theses

The simplest and the most common way of comparing two random variables is through their means and variances. It may happen that in some cases the median of X is larger than the median of Y, while the mean of X is smaller than the mean of Y. However, this confusion will not arise if the random variables are stochastically ordered. Similarly, the same may happen if one would like to compare the variability of X with that of Y based only on numerical measures of variability. Besides, these characteristics of distributions might not exist in some cases. In most …