International Journal of Multivariate Data Analysis (4 papers in press)
USE OF AUXILIARY VARIABLES IN SEARCHING EFFICIENT ESTIMATOR OF POPULATION MEAN
by Subhash Yadav, Dinesh Sharma, S.S. Mishra, Alok Shukla
Abstract: The paper deals with the improvement in Yadav et al. (2016) estimator of the population mean using known coefficient of kurtosis and median of the auxiliary variable. The large sample properties of the estimator, bias and mean squared error (MSE), have been calculated up to the first order of approximation. The optimum values of the characterizing scalars which minimize the MSE of the proposed estimator have been obtained. A comparative study has been conducted with the existing estimators of population mean using auxiliary variable under simple random sampling scheme. To justify the improvement of proposed estimator over Yadav et al. (2016) and other estimators of the population mean, an empirical study is also presented by calculating the mean squared errors of the different estimator of the population mean under simple random sampling.
Keywords: Ratio-cum-product estimator; coefficient of kurtosis; median; bias; MSE; Efficiency.
Cluster-Based Multinomial Logistic Regression Analysis of Saltwater Anglers Concerns of Marine Environmental Threats
by Yeong Nain Chi
Abstract: This study utilized cross-sectional data extracted from the 2013 National Saltwater Angler Survey to examine saltwater anglers concerns to the threats of marine environment, to identify groups exhibiting common patterns of responses, and to examine the association between socio-demographic characteristics and the groups identified. Concerns of marine environmental threats from these participants were examined through factor analysis which identified three reliable factors. Cluster analysis was employed to identify three prominent groups. Statistical tests were employed to investigate the association between socio-demographic characteristics, including age, gender, income level, educational level, region of the respondent, and the saltwater angler groups identified. Results of this study may provide insight regarding the concerns of marine environmental threats from saltwater anglers as an indicator of potential participation and behavior of saltwater recreational fishing activities.
Keywords: Saltwater Recreational Fishing; Anglers; Marine Environmental Threats; Factor Analysis; Cluster Analysis; Multinomial Logistic Regression Analysis.
Innovation output estimation method for a national innovation system: Application to the BRICS countries
by Luciele Cristina Pelicioni, Joana Ramos Ribeiro, Rodrigo Arnaldo Scarpel, Tessaleno Devezas, Mischel Carmen Neyra Belderrain, Francisco Cristovão Lourenço De Melo
Abstract: The evaluation of the ability of a country to promote innovation is a valuable step to assist countries in designing suitable economic policies. A usual approach to perform such evaluation and for ranking countries according to their innovation rate is the usage of innovation indices. However, those indices are not appropriate for evaluating whether a set of countries are producing innovation below of what is expected from them. Thus, the aim of this study was to create a model using structural equation model (SEM) to allow evaluating the innovation capacity of any country and to calculate the expected outputs as a function of the estimated inputs. The model showed that the countries belonging to the BRICS group, except for South Africa, presented outputs close to or above the expected for these countries, achieving a performance similar to the group of countries with negative scores of input and output factors.
Keywords: BRICS; Causal relationships; Confirmatory Factor Analysis; Global Innovation Index; Innovation Capacity Performance; Innovation Output; Innovation Index; Multiple Regression; National Innovation System; Structural Equation Modelling.
by Maria Helena Pestana, Margarida Rolland Sobral
Abstract: A limit number of studies have applied bibliometric visualisation to explore the network structure of Alzheimers Disease (AD). This paper uses CiteSpace, Carrot and VOSviewer to analyse and visualise the intellectual structure of AD, characterizing, quantitatively and qualitatively, the global scientific outputs, and identifying their trends. The 9,757 articles obtained from the science citation index expanded database (SCI-E), from Web-of-Science, were analysed. The publication data is analysed computationally to identify publication patterns, a rate of growth of publications, types of authorship collaboration, the most productive authors, countries, institutions, journals, keywords, the citation and keyword patterns, the hotspots and the areas of research on the AD. The paper presents a detailed analytical mapping of AD research and charts the progress of discipline with various useful parameters. The authors expect to contribute to the theory, supplying researchers with new tools and enabling practitioners to improve their knowledge about the AD evolution and trends.
Keywords: Bibliometric analysis; Scientific outputs; Alzheimer; Keywords analysis; Collaboration network; Research trend.