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Working Papers | 2013

Some Auto-power Divergence Measures for Stationary Time Series of Categorical Data

Atanu Biswas, Maria del Carmen Pardo, and Apratim Guha

For stationary time series of nominal categorical data or ordinal categorical data (with arbitrary ordered numberings of the categories), autocorrelation does not make much sense. Biswas and Guha (2009) used mutual information as a measure of association and introduced the concept of auto-mutual information in this context. In this present paper we generalise to auto-power divergence measures for this purpose and study some special cases. Theoretical properties and simulation results are given along with an illustrative real data example.

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Working Papers | 2013

On Estimation of Number of Species and Biodiversity

Atanu Biswas and Apratim Guha

Suppose S is the unknown number of species in a community, and the sample consists of m distinct species, fj species are represented j times in the sample, j = 1; 2; ... ; k. Let f0 be the number of missing species in the sample. Several existing approaches are available for estimating f0 (and hence S), and also the measure of biological diversity given by Shannons index of diversity, denoted by H. The standard approach, although derived from elegant distribution theory, uses some sort of approximation, and essentially ignores all the species in the sample with counts two or more. The present paper proposes an alternative estimate of f0, and hence of H, using all the observed counts f1; f2; ; fk. The performance of the proposed estimates are studied and compared with the existing competitors through simulations. Some real data sets are used for illustration.

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Working Papers | 2013

Identifying defective valves in a blowout preventer valve network

Diptesh Ghosh

Blowouts are nancially damaging for drilling companies and are ecological hazards. Hence
blowout prevention equipment is critical infrastructure for drilling companies. Blowout preventer
valves are important components of blowout prevention equipments and need to be checked
regularly. However, since these valves are often physically inaccessible, they are checked in
batches called test sets. In this paper we present an exact method to check the functional status
of all blowout preventer valves using a minimum number of test sets. We also present a heuristic
method to identify malfunctioning valves if they exist. We illustrate both methods using a real
world example.

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Working Papers | 2013

Strategies To Improve Urban Water Delivery In West Bengal, India: An Analysis Of Water Institutions And Benchmarking Of Water Delivery Organizations

Tirthankar Nag and Amit Garg

The study examines the status of urban water delivery in India through a case study of the state of West Bengal in India. The state has been selected as a unit of study to bring out the regional variances that are not captured at a more aggregate or country level study. The study focuses on various types of urban local bodies in the state, the organizational and institutional structure for water delivery and issues around them. The study also benchmarks various urban local bodies for their water service delivery through data envelopment analysis. The study finds that in the current state of fragmented institutions and shared responsibilities between various water organizations, there needs to be a focused policy guideline for integrated development of the water sector in the state. The study also identifies certain categories of urban local bodies, for which there are further scope for efficiency improvement.

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Working Papers | 2013

SB-robustness of Performance Measures of Control Chart

A. K. Laha and Pravida Raja

Control charts play a very important role in the control of manufacturing processes. In this paper we consider the commonly used performance measures for control charts and study their SB-robustness. It is shown that the False Alarm Probability, Average Sample Number (ASN) when the process is in-control, No-Signal Probability and ASN when the process is out-of-control are all SB-robust at the family of all normal distributions with bounded mean and standard deviation. It is also shown that these performance measures are not SB-robust at the larger family of normal distributions with unbounded mean and standard deviation.

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Working Papers | 2013

Development of a Causal Framework linking High Perofrmance HRM Practices, Positive Psychological Capital, Creative Behaviours

Vishal Gupta

Synthesizing the ideas of high-performance Human Resource Management (HRM), positive psychological capital, and componential theory of creativity, the present study develops a multi-level causal framework linking high-performance work practices (HPWP), positive psychological capital, employee creative performance behaviors and creative performance. The paper argues that to provide a convincing explanation of the association between HRM practices and creativity, we need to improve our theoretical understanding in three key areas. These are the nature of HRM, and especially the rationale for the specific lists of HR practices; the linkage between HRM practices and employee creativity; and the 'black-box' linking HRM practices and employee creativity. A model is presented to explore these linkages. The existing literatures on HRM, Creativity and PsyCap are reviewed and directions for future research are provided.

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Working Papers | 2013

A Memory-Aided Broadcast Mechanism for Enabling a Rural Community Radio on an Ad-hoc peer-to-peer Mobile Network

Kavitha Ranganathan and Sonia Arora

This paper investigates deploying a village level community-radio application on top of a MANET comprising completely of basic mobile phones. We envision a system, where any user in the network is equally empowered to generate and distribute audio content to the entire network, using his or her mobile phone. The paper focuses on the study of suitable broadcast algorithms for the network. In this context, we propose a novel broadcast scheme where nodes bank on their memory to decide whether to forward packets of an audio stream-capitalizing on their past behavior to stabilize on fixed routes for the entire stream. In our scheme called Environs Aware Broadcast Mechanism (EABA), a node gauges the local mobility around itself, and uses that to decide which broadcast mechanism to use. When mobility is high, it uses SBA (Scalable Broadcast Algorithm), a popular neighbor -knowledge broadcast algorithm with high overheads, but when mobility is low, it switches to MaBA (Memory-aided Broadcast Algorithm). Extensive simulations on a village-level MANET, confirm that EABA is successful in substantially reducing jitter, latency and packet loss: all critical metrics for an audio application. At the same time, EABA does not incur other overheads and maintains the same levels of reachability and efficiency as SBA

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Working Papers | 2013

Corporate Governance: Financial Regulators and Courts Need To Be On the Same Page

Anurag K. Agarwal

Real corporate governance requires tough financial regulators which effectively work to safeguard investors' interests in securities and endeavour to create a proper environment for the securities market to develop. The financial regulators-Securities and Exchange Board of India, SEBI in India, and Securities and Exchange Commission, SEC in the US-have been created by the legislature. They are independent expert bodies and are vested with remarkable powers, but they have to work within the framework of law, which is interpreted by the courts. This paper examines the role of courts vis-à-vis expert bodies in general and financial regulators in particular, and highlights the importance of the two being on the same page for effective corporate governance.

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Working Papers | 2013

Advertisement Placement in TV Programs: Different Roles of ELM and Mood Protection Mechanism

Mayank Jyotsna Soni

This study explores how involvement of the audience with cognitive/affective program influence their processing of advertisements aired in between the program because of varying involvement within program. An experimental design was conducted. Cognitive ad recall was found to be higher when involvement with program (both cognitive and affective) is low than when involvement with program is high. Affective ad recall was found to be lower when involvement with program (cognitive and affective) is low than when the involvement with program is high. This study will be useful for managers in choosing television slots to broadcast their advertisements. ELM, Mood Protection Mechanism and Resource Matching Hypothesis are used to explain information processing mechanisms. The results also indicated a need of extending existing information processing theories.

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Working Papers | 2013

Sectoral Choice of Credit in Rural India

Debdatta Pal and A. K. Laha

This article examines, what makes rural household a preferred choice for formal lenders? It develops sample selected ordered probit model to address this question. While, the selection equation models the determinants of access to credit, an ordered probit model is used to determine the factors affecting the choice of credit sources in a hierarchical order. Using household data from six Indian states this study finds corroborative evidence that relatively resource rich households even while staying at distant location enjoy greater access to formal creditors. It also identifies a new factor i.e., interlinked credit as a significant variable influencing the access to formal credit.

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