Arijit Chaudhuri

Bio: Arijit Chaudhuri is an academic researcher from Indian Statistical Institute. The author has contributed to research in topics: Population & Estimator. The author has an hindex of 21, co-authored 107 publications receiving 2288 citations.

Randomized Response : Theory and Techniques

Abstract: Offering a concise account of the most appropriate and efficient procedures for analyzing data from queries dealing with sensitive and confidential issues- including the first book-length treatment of infinite and finite population set-ups - this volume begins with the simplest problems, complete with their properties and solutions, and proceeds to incrementally more difficult topics. Randomized Response is mandatory reading for statisticians and biostatisticians, market researchers, operations researchers, pollsters, sociologists, political scientists, economists and advanced undergraduate and graduate students in these areas.

Survey sampling : theory and methods

Abstract: Foreword Preface to the Second Edition Preface to the First Edition ESTIMATION IN FINITE POPULATIONS: A UNIFIED THEORY Introduction Elementary Definitions Design-Based Inference Sampling Schemes Controlled Sampling STRATEGIES DEPENDING ON AUXILIARY VARIABLES Representative Strategies Examples of Representative Strategies Estimation of the Mean Square Error Estimation of Mp(t ) for Specific Strategies Calibration CHOOSING GOOD SAMPLING STRATEGIES Fixed Population Approach Superpopulation Approach Estimating Equation Approach Minimax Approach PREDICTORS Model-Dependent Estimation Prior Distribution-Based Approach ASYMPTOTIC ASPECTS IN SURVEY SAMPLING Increasing Populations Consistency, Asymptotic Unbiasedness Brewer's Asymptotic Approach Moment-Type Estimators Asymptotic Normality and Confidence Intervals APPLICATIONS OF ASYMPTOTICS A Model-Assisted Approach Asymptotic Minimaxity DESIGN- AND MODEL-BASED VARIANCE ESTIMATION Ratio Estimator Regression Estimator HT Estimator GREG Predictor Systematic Sampling MULTISTAGE, MULTIPHASE, AND REPETITIVE SAMPLING Variance Estimators Due to Raj and Rao in Multistage Sampling: More Recent Developments Double Sampling with Equal and Varying Probabilities: Design-Unbiased and Regression Estimators Sampling on Successive Occasions with Varying Probabilities RESAMPLING AND VARIANCE ESTIMATION IN COMPLEX SURVEYS Linearization Jackknife Interpenetrating Network of Subsampling and Replicated Sampling Balanced Repeated Replication Bootstrap SAMPLING FROM INADEQUATE FRAMES Domain Estimation Poststratification Estimation from Multiple Frames Small Area Estimation Conditional Inference ANALYTIC STUDIES OF SURVEY DATA Design Effects on Categorical Data Analysis Regression Analysis from Complex Survey Data RANDOMIZED RESPONSE SRSWR for Qualitative and Quantitative Data A General Approach INCOMPLETE DATA Nonsampling Errors Nonresponse Callbacks Weight Adjustments Use of Superpopulation Models Adaptive Sampling and Network Sampling Imputation EPILOGUE Appendix References List of Abbreviations, Special Notations, and Symbols Author Index Subject Index

A Prospective Community-Based Study of Stroke in Kolkata, India

Abstract: Background and Purpose— Information on essential stroke parameters are lacking in India. This population-based study on stroke disorder was undertaken in the city of Kolkata, India, to determine the subtypes, prevalence, incidence, and case fatality rates of stroke. Methods— This was a longitudinal descriptive study comprising 2-stage door-to-door survey of a stratified randomly selected sample of the city population, conducted twice per year for 2 successive years from March 2003 to February 2005. Results— Out of the screened population of 52 377 (27 626 men, 24 751 women), the age standardized prevalence rate of stroke to world standard population is 545.10 (95% CI, 479.86 to 617.05) per 100 000 persons. The age standardized average annual incidence rate to world standard population of first-ever-in-a-lifetime stroke is 145.30 (95% CI, 120.39 to 174.74) per 100 000 persons per year. Thirty-day case fatality rate is 41.08% (95% CI, 30.66 to 53.80). Women have higher incidence and case fatality rates. Des...

Randomized Response and Indirect Questioning Techniques in Surveys

Abstract: Why We Need One More Monograph on Randomized Response Warner's Randomized Response Technique Introduction Warner Model Simple Random Sampling with Replacement Chaudhuri and Pal's Estimators Chaudhuri, Bose, and Dihidar's Estimators Inverse SRSWR Randomized Response Technique in General Sampling Design Introduction Warner's Model Unrelated Question Model Kuk's RRT Christofides's RRT Forced Response Scheme Mangat and Singh's RRT Mangat's Scheme Mangat, Singh, and Singh's Scheme Singh and Joarder's Scheme Dalenius and Vitale's Scheme Takahasi and Sakasegawa's Scheme Modified by Pal Liu, Chow, and Mosley's RRT Maximum Likelihood Approach Introduction Illustrations Optional Randomized Response Technique Introduction Illustrations Comments Protection of Privacy Introduction Illustrations Quantitative Characteristics Introduction Review of Literature Other Indirect Questioning Techniques Introduction Item Count Technique Nominative Technique The Three-Cards Method Miscellaneous Techniques, Applications, and Conclusions Introduction Review Epilogue Illustrative Simulated Empirical Findings Warner's RR versus Unrelated Question Model-Based RR in Unequal Probability Sampling as against Equal Probability Sampling Simulated Illustration of a Numerical Study of "Protection of Privacy" in RR Surveys Concluding Remarks References Index

An epidemiologic study of mild cognitive impairment in Kolkata, India

Abstract: Objectives: To estimate the prevalence of two types of mild cognitive impairment (MCI)—amnestic and multiple domain types—among nondemented and nondepressed elderly subjects aged 50 and older. Methods: The study was carried out in Kolkata, the eastern metropolis of India. A cross-sectional community screening was carried out, and 960 subjects were selected by systematic random sampling for the assessment of cognitive function with the help of a validated cognitive questionnaire battery administered through house-to-house survey. A case-control study was also undertaken to identify potential risk factors through univariate analysis. Results: Ultimately, full evaluation of cognitive function was possible in 745 of 960 subjects. An overall prevalence of MCI detected based on neuropsychological testing was 14.89% (95% CI: 12.19 to 17.95). Prevalence of the amnestic type was 6.04% (95% CI: 4.40 to 8.1) and that of the multiple domain type was 8.85% (95% CI: 6.81 to 11.32). Adjusted for age, education. and gender, the amnestic type was more common among men and the multiple domain type among women with advancement of age. Rates differed considerably with educational attainment. Hypertension and diabetes mellitus were the major risk factors for both types of MCI. Conclusion: In this first community-based study of mild cognitive impairment (MCI) from India, prevalence of the amnestic type is comparable with and that of the multiple domain type is less than the prevalence in developed countries. Variations in age, education, and gender specific prevalence of MCI of both types were encountered. The putative risk factors identified merit further study.

Determinants of social desirability bias in sensitive surveys: a literature review

Abstract: Survey questions asking about taboo topics such as sexual activities, illegal behaviour such as social fraud, or unsocial attitudes such as racism, often generate inaccurate survey estimates which are distorted by social desirability bias. Due to self-presentation concerns, survey respondents underreport socially undesirable activities and overreport socially desirable ones. This article reviews theoretical explanations of socially motivated misreporting in sensitive surveys and provides an overview of the empirical evidence on the effectiveness of specific survey methods designed to encourage the respondents to answer more honestly. Besides psychological aspects, like a stable need for social approval and the preference for not getting involved into embarrassing social interactions, aspects of the survey design, the interviewer’s characteristics and the survey situation determine the occurrence and the degree of social desirability bias. The review shows that survey designers could generate more valid data by selecting appropriate data collection strategies that reduce respondents’ discomfort when answering to a sensitive question.

The prevalence of Parkinson's disease: A systematic review and meta‐analysis

Abstract: Parkinson's Disease (PD) is a common neurodegenerative disorder. We sought to synthesize studies on the prevalence of PD to obtain an overall view of how the prevalence of this disease varies by age, by sex, and by geographic location. We searched MEDLINE and EMBASE for epidemiological studies of PD from 1985 to 2010. Data were analyzed by age group, geographic location, and sex. Geographic location was stratified by the following groups: 1) Asia, 2) Africa, 3) South America, and 4) Europe/North America/Australia. Meta-regression was used to determine whether a significant difference was present between groups. Forty-seven studies were included in the analysis. Meta-analysis of the worldwide data showed a rising prevalence of PD with age (all per 100,000): 41 in 40 to 49 years; 107 in 50 to 59 years; 173 in 55 to 64 years; 428 in 60 to 69 years; 425 in 65 to 74 years; 1087 in 70 to 79 years; and 1903 in older than age 80. A significant difference was seen in prevalence by geographic location only for individuals 70 to 79 years old, with a prevalence of 1,601 in individuals from North America, Europe, and Australia, compared with 646 in individuals from Asia (P < 0.05). A significant difference in prevalence by sex was found only for individuals 50 to 59 years old, with a prevalence of 41 in females and 134 in males (P < 0.05). PD prevalence increases steadily with age. Some differences in prevalence by geographic location and sex can be detected. © 2014 International Parkinson and Movement Disorder Society

Rate of progression of mild cognitive impairment to dementia – meta-analysis of 41 robust inception cohort studies

Abstract: Objective: To quantify the risk of developing dementia in those with mild cognitive impairment (MCI). Method: Meta-analysis of inception cohort studies. Results: Forty-one robust cohort studies were identified. To avoid heterogeneity clinical studies, population studies and clinical trials were analysed separately. Using Mayo defined MCI at baseline and adjusting for sample size, the cumulative proportion who progressed to dementia, to Alzheimer’s disease (AD) and to vascular dementia (VaD) was 39.2%, 33.6% and 6.2%, respectively in specialist settings and 21.9%, 28.9% and 5.2%, respectively in population studies. The adjusted annual conversion rate (ACR) from Mayo defined MCI to dementia, AD and VaD was 9.6%, 8.1% and 1.9%, respectively in specialist clinical settings and 4.9%, 6.8% and 1.6% in community studies. Figures from non-Mayo defined MCI and clinical trials are also reported. Conclusion: The ACR is approximately 5–10% and most people with MCI will not progress to dementia even after 10 years of follow-up.

Mild cognitive impairment: ten years later.

Abstract: In the past 10 years, there has been a virtual explosion in the literature concerning the construct of mild cognitive impairment. The interest in this topic demonstrates the increasing emphasis on the identification of the earliest features of cognitive disorders such as Alzheimer disease and other dementias. Mild cognitive impairment represents the earliest clinical features of these conditions and, hence, has become a focus of clinical, epidemiologic, neuroimaging, biomarker, neuropathological, disease mechanism, and clinical trials research. This review summarizes the progress that has been made while also recognizing the challenges that remain.

Mild cognitive impairment: A concept in evolution

Abstract: The construct of mild cognitive impairment (MCI) has evolved over the past 10 years since the publication of the new MCI definition at the Key Symposium in 2003, but the core criteria have remained unchanged. The construct has been extensively used worldwide, both in clinical and in research settings, to define the grey area between intact cognitive functioning and clinical dementia. A rich set of data regarding occurrence, risk factors and progression of MCI has been generated. Discrepancies between studies can be mostly explained by differences in the operationalization of the criteria, differences in the setting where the criteria have been applied, selection of subjects and length of follow-up in longitudinal studies. Major controversial issues that remain to be further explored are algorithmic versus clinical classification, reliability of clinical judgment, temporal changes in cognitive performances and predictivity of putative biomarkers. Some suggestions to further develop the MCI construct include the tailoring of the clinical criteria to specific populations and to specific contexts. The addition of biomarkers to the clinical phenotypes is promising but requires deeper investigation. Translation of findings from the specialty clinic to the population setting, although challenging, will enhance uniformity of outcomes. More longitudinal population-based studies on cognitive ageing and MCI need to be performed to clarify all these issues.