Research Publications

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Author: search.filters.author.Chakrabartty, Satyendra NathHas files: No

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    Cosine similarity approaches to reliability of likert scale and items /
    (Hyperion University, 2018-02-02) Chakrabartty, Satyendra Nath
    Based on cosine similarities, the paper proposes two non-parametric methods of finding reliability of Likert items and Likert scale from single administration of the questionnaire, considering only the frequency or proportion for each cell of the Item-Response category matrix without involving any assumptions of continuous nature or linearity or normality for the observed variables or the underlying variable being measured. Each method enables to find reliability irrespective of distribution of the observed or underlying variables and avoiding test of uni-dimensionality or assumption of normality for Cronbach's alpha or bivariate normality for polychoric correlations. The proposed methods thus are considered as improvement over the existing ones. Reliability as per Bhattacharyya's measure appears to be preferred over the Angular Association method as the former expresses test reliability as a function of item reliabilities. In addition to offering the computational steps, empirical verification with real data is given to illustrate the concepts and usefulness of the proposed non-parametric reliability procedures.
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    Assessing direction of india’s exports: a dynamic framework /
    (ASEAN India Centre & ASEAN Studies Center, 2024-02-25) Chakrabartty, Satyendra Nath
    Decision on trade policies with emphasis on bilateral trade relationships needs knowledge about the direction of exports of the exporting country along with associated changes like degree of specialisation, etc. The direction of export for a product or sector can be taken as a set consisting of destination countries (DCs) and corresponding export potentiality. The set reflects the direction, composition and value of trade potentials and helps to decide export-boosting measures of several sectors, focusing on a country. The paper suggests the use of ratio and geometrically aggregated revealed comparative advantage (RCA) values for individual and combined sector growth (positive or negative), respectively. This approach overcomes the static properties of RCA and shift-share analysis typically used to reveal the patterns of trade direction. The pattern is investigated by geometric aggregation of ratios of RCA at the current period over the base period for each sector. The index follows log-normal distribution and shows fluctuations of RCA for a product/sector across time. Such curves of fluctuations for different countries may facilitate meaningful inter-country comparisons. Second, this paper suggests the use of bilateral RCA to determine the direction of India’s exports for a particular sector, enabling the determination of its potential markets.
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    Port sustainability index: methodological issues /
    (Medwin Publishers, 2024-02-06) Chakrabartty, Satyendra Nath
    Approaches to find impact of maritime transport on environmental performance of ports or port regions through models with different sets of assumptions suffer from limitations. The paper describes an integrated Port Sustainability Index (PSI) by combining relevant environmental aspects of port processes and operations by transforming each indicator to follow normal distribution and taking PSI as sum of such normally distributed indicator scores, avoiding skew and outliers. Thus, there is no bias for developed or under-developed ports. PSI is simple and satisfies desired properties including assessment of effectiveness of policy measures through responsiveness, statistical tests of equality of mean PSI across ports. Dimensions of PSI can be ranked by respective elasticity. The method also helps to find growth curve of PSI of a port over time. Proposed PSI may help port authorities to evaluate their performance from the sustainability angle along with performances in the relevant dimensions and may serve as a strategic tool for port environmental performance management.
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    Drug addiction and quality of life: methodological issues /
    (URF Publishers, 2023-06-09) Chakrabartty, Satyendra Nath
    Objective: Substance abuse research data containing categorical and continuous variables often violate assumptions of parametric statistical methods. Clustering of individuals, lack of repeated measurements, missing data, non-representative samples, etc. aggravates the problem. Quality of life (QoL) measures suffer from meaningful application of statistical methods. The paper describes statistical approaches which fit well with structure of drug addiction data and measures of QoL, facilitating better analysis and interpretations of results. Method: Converting ordinal item scores to normally distributed continuous scores in the range [1-100], irrespective of number of response-category in items. Such transformations fit well with structure of drug addiction data and measures of QoL and facilitate better analysis and interpretations of results. Results: Proposed method enables parametric statistical analysis leading to meaningful comparisons and inferences, finding equivalent scores, computation of responsiveness of the scale i.e., ability to assess changes across time and psychometric qualities like reliability, as per definition, Factorial validity reflecting the main factor for which the test was developed. Conclusions: Considering theoretical advantages, the proposed method generating normally distributed scores is recommended. Future studies with longitudinal data suggested finding sensitivity with emphasis on progression of disease and to different therapeutic interventions.
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    Association between multiple sclerosis and cardiovascular dysfunction /
    (Crimson Publishers, 2023-04-28) Chakrabartty, Satyendra Nath
    Background: Empirical studies indicate association of Multiple Sclerosis (MS) with increased risks of Cardiovascular Diseases (CVDs). However, controversial results emerged. Objectives: To measure the association between MS and CVD using pathological data and scales to assess s MS and CVD. Methods: The paper provides an assumption-free method to convert item scores to normally distributed scale scores, avoiding limitations of scales to assess MS or CVD satisfying desired properties. Binary and categorical pathological data may also be transformed to follow normal and data in ratio scale may be standardized followed by transformation and added with scale scores. Result: Association through contingency table need meaningful scale scores to obtain the cell frequencies. Proposed scores can classify the sample in relevant classes through equivalent scores and find cell frequencies. Associations by correlations are preferred over frequency based measures. However, correlations may not imply linearity. Conclusion: Normally distributed proposed scores ensure meaningful addition of item scores to get dimension/scale scores for individuals and contribute to improve scoring of instruments. Such scores facilitate better comparisons, measurement of association, statistical tests and identification of areas requiring changes in clinical practice, treatment protocols, community program management and estimating population parameters and testing of statistical hypothesis.
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    Constructing aggregated revealed comparative advantage index of a country /
    (ASEAN-India Centre & ASEAN Studies Center, 2023-02-12) Chakrabartty, Satyendra Nath
    The measures of revealed comparative advantage (RCA) with multiplicative specification and dependency on world trade of export items are incomparable across time and places. Intra-country comparisons by Balassa RCA and its variants are problematic, calling for a method of aggregating RCA of all sectors of a country reflecting the overall export potential of the country. Overall RCA of a country (RCA) is necessary to know the country’s RCA of all the export items as a function of trade flows relative to a point of reference, that is, a base period. The article proposes geometric aggregation of the ratio of RCA at the current period over the base period for each sector to get by a continuous, monotonically increasing function of time, satisfying time-reversal test, formation of chain indices and generates time-series data. Progress path of and similar path of jth sector may help policymakers to decide on appropriate action for the economy and individual sectors. Distribution of will approach lognormal. Knowledge of distributions of for different countries helps to have a better inter-country comparison. The similarity of two RCA curves may be evaluated by similarity measures. An empirical illustration of the proposed method is given.
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    Improved scoring of satisfaction with life scale: scoring of swls /
    (RevistaMultidisciplinar.com, 2023-01-01) Chakrabartty, Satyendra Nath
    The Satisfaction with Life Scale (SWLS), a 5-item instrument with 7 response-categories per item, measures cognitive judgments of satisfaction with one's life using summative scoring where higher score implies higher life satisfaction. Discrete scores of SWLS using Likert-type items fail to satisfy equidistant property and do not consider distributions of item scores or scale scores. The paper gives an assumption-free method to convert item scores of SWLS to continuous scores following normal distribution and scale score is taken as sum of such normally distributed item scores. The proposed scores avoiding tied-scores facilitate better admissibility of arithmetic aggregation, meaningful comparisons, ranking, classification of individuals, assessment of progress/deterioration across time and undertaking parametric statistical analysis. In addition, it helps to assess changes in successive time-periods for an individual or a group of individuals, drawing of progress-paths and test of significance of progress or deterioration. Normality of proposed scores facilitates finding equivalent scores of several measures of life satisfactions with different scale formats and different score-ranges. Empirical illustration is given with hypothetical data. The proposed method is recommended to enhance the utilization of the SWLS for better measurement of satisfaction with life along with meaningful comparisons and inferences.
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    Speed and Power Indices of tests and items /
    (revistamultidisciplinar.com, 2023-01-01) Chakrabartty, Satyendra Nath
    A simple index is proposed to measure speed or power components of a test. The index is independent of position of the items and provides necessary and sufficient condition for pure speed test and pure power test and enables testing of statistical hypothesis to infer that the test can be taken as a speed test or a power test. Similar index of an item is also proposed to reflect whether the item is a speed item or a power item. The proposed index C is a ratio such that C = 0 ⟺Pure power test and C = 1⟺Pure speed test facilitating computation of similar index of each item and statistical test of significance. Properties of the index discussed. Operational method outlined to modify a test to speed or power test. Items can be ranked with respect to such item-wise index. Identification of power items and speed items help to modify the test to a speed or power test by deleting items in stages, if speediness (or power) is not intended. Relationship between index for the test and item-wise indices derived.
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    Gender equality and goal 5 of sustainable development goals /
    (Medwin Publishers, 2023-01-01) Chakrabartty, Satyendra Nath
    With 14 indicators distributed over nine targets, SDG-5 aims at achieving gender equality and empowerment of all women and girls by 2030 for all countries agreed to work towards achieving them. NITI Aayog of Govt. of India selected six indicators towards improvement in SDG-5.Focusing attention to SDG-5 only, the paper proposes simple method of aggregating indicators of SDG-5 and discusses properties of the proposed methods. Each of the indicators was expressed in terms of proportions which were combined to reflect overall proportion for a State/UT at current period. The proposed method of combining indicators expressed as proportions is simple, appealing and helps to assess current status (achievement) of a State by computing combined proportion. Current status of the States can similarly be combined to get current status of a country and its distance from the 2030 targets. Similar procedure may be extended to find current status of the world by combining the country-wise current status. Measures of percentage improvement or deterioration at country/State levels at a period from the previous period were discussed. Important inferences on comparison of countries may be drawn on the basis of path of improvement registered by a State or country. Future studies suggested.
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    Assessing a country's sector-specific logistics performance: the case of india's marine-product sector /
    (Penerbit UMT, 2022-12-30) Chakrabartty, Satyendra Nath
    Country-wise Logistics Performance Index (LPI) is insufficient to guide changing policies for different sectors with varied logistics requirements and perspectives. Each perspective has various measures, and hence a battery of scales is mandated to measure the performance for an individual sector like marine, agriculture, and similar. For the marine-product sector of India, scores are transformed and combined to follow normal distributions enabling parametric analysis. A method of sector-specific logistics performance index (LPI-S) is proposed addressing multi-dimensional, multi-scale response categories satisfying the desired properties of an index. An empirical illustration is given to assess LPI-S for the marine-product sector in India, combining responses of 141 Indian marine exporters in a battery with nine dimensions. The proposed method generates continuous, monotonic data, and distributions of dimension/battery scores are normal. The LPI-S scores have better arithmetic aggregation admissibility, even if lengths of dimensions are different. In addition, it identifies critical dimensions, detects changes by longitudinal data, and dimension-wise elasticity reflecting the sensitivity of the dimension from snap-shot data. Irrespective of dimensions and types of data, the proposed methodology uses the sensitivity of a dimension on LPI-S to help policy makings separately for individual categories to improve logistics efficiency. The study identified eight crucial dimensions associated with marine product logistics. The sensitivity of these dimensions in the descending order of importance were - Information system, Regulatory process, Safety & Security issues, Timeliness and Completeness efficiency, Sustainability in logistics, Operating conditions, Logistics facility pricing, Quality of Logistic services, Transportation Networks and Logistics infrastructure. Such ordering of dimensions help in deciding policy priorities.