Cluster Analysis Of Factor Scores Research Articles

Typology of Brazilian dairy farms based on vulnerability characteristics

Vulnerability has been a recurring theme in animal production research around the world, as it can lead to a series of outcomes, such as abandonment of the activity. Nevertheless, in Brazil, the fifth-largest milk producer in the world, studies assessing dairy farmers' vulnerabilities are scarce. Better understanding of dairy farm vulnerability may contribute to reducing the consequences of vulnerability. In view of these limitations, we sought to analyze the typology of dairy farms based on vulnerability characteristics. We applied on-site questionnaires to 128 dairy farmers located in Paraná State, Brazil. Structural, productive, and socioeconomic data were collected and subjected to factor analysis. Two vulnerability indicators were identified: F1, productive and economic indicator; and F2, feed self-sufficiency indicator. Hierarchical cluster analysis of factor scores revealed three groups of dairy farms: Group 1, highly vulnerable; Group 2, less vulnerable; and Group 3, non-vulnerable. Dairy farms with higher vulnerability represented most of the sample, followed by less vulnerable and non-vulnerable dairy farms. Our findings indicated that the productive and economic characteristics of farms contributed the most to explaining differences in vulnerability, followed by feed self-sufficiency characteristics. Social characteristics of farmers were not important in differentiating the analyzed sample. There was an interdependent relationship between vulnerability indicators, namely productive and economic characteristics and feed self-sufficiency.

Utility of the Neuropathic Pain Symptom Inventory in people with spinal cord injury.

Cohort/psychometric study OBJECTIVES: The primary objective was to determine the psychometric properties and the utility of the Neuropathic Pain Symptom Inventory (NPSI) in subgrouping people with moderate to severe neuropathic pain after spinal cord injury (SCI). University-based laboratory in Miami, FL USA. Seventy-two people with chronic SCI and neuropathic pain were included in this study. The NPSI, Numeric Rating Scale (NRS), Multidimensional Pain Inventory pain severity and perceived support subscales (MPI-PS and MPI-S, respectively), and the Coping Strategies Questionnaire were administered. The NPSI was administered twice, with a 2-4-week period between measurement sessions. The NPSI total score demonstrated good internal consistency with a Cronbach's alpha of 0.70. The test-retest reliability (intraclass correlations) ranged from 0.65 to 0.73 for the NPSI subscores and 0.79 for the total NPSI score. Further, construct validity was supported by moderate and significant positive correlations with the pain intensity NRS and pain severity subscale of the MPI (MPI-PS) (r > 0.40). Cluster analysis of factor scores derived from NPSI subscales, NRS, and MPI-PS scores revealed three distinct subgroups: (1) low-moderate, (2) moderate, and (3) high pain symptom severity with mean NPSI sum scores of 7.1, 17.5, and 33.8, respectively. The NPSI demonstrated good psychometric properties in people with neuropathic pain after SCI. Moreover, it has utility for establishing pain symptom phenotypes.

The prioritization and verification of IT emerging technologies using an analytic hierarchy process and cluster analysis

Abstract This study proposes a quantitative technology forecasting method for prioritizing investments using analytic hierarchy process (AHP) analysis and a verification process to evaluate the prioritization using factor analysis and cluster analysis of the factor scores. To verify the prioritization process of emerging technologies, this study completed two surveys of experts. Cluster analysis of the factor scores based on the second survey is used to verify the results of prioritization using AHP analysis based on the first survey. The results suggest high hit ratios between the prioritization using AHP analysis and the cluster analysis of factor scores. This confirms that the AHP method is significantly reliable as a method for selecting promising electronic device technologies. As the emerging technology market is more changeable than ever before, the study's prioritization and verification process provides a relevantly robust solution.

Motive Based Segmentation of the Cultural Tourism Market: A Study of Turkish Domestic Tourists

This article examines cultural tourists' motivations for travel and provided support for the idea that cultural tourists are not solely motivated by the potential for deep cultural experiences. Face-to-face interviews were conducted with 270 domestic tourists in 52 provinces in Turkey whose primary travel purpose was cultural. Factor analysis indicated eight motivation factors, which were termed: “Adventure, Creativeness and Challenge,” “Knowledge and Experience,” “Achievement and Autonomy,” “Rest and Relaxation,” “Sports and Socialization,” “Escape,” “Family Togetherness,” and “Fun and Travel Bragging.” Cluster analysis of factor scores indicated that cultural tourists could be classified into five distinct groups, each with different travel motivations. The accuracy of the cluster classification was tested using discriminant analysis. Delineated clusters were labelled: “Relaxation Seekers,” “Sports Seekers,” “Family Oriented,” “Escapists,” and “Achievement and Autonomy Seekers.” Each tourist type possessed different demographic and trip behavior characteristics. Interestingly, none of the groups was primarily motivated by the factors that are most closely linked to ideas of culture. Although the results cannot be generalized beyond the study population, this study confirmed the applicability of the methodology for segmenting the Turkish domestic cultural tourism market in terms of travel motivations. The implications of marketing to various tourist types are discussed.

Identification of probable groundwater paths in the Amargosa Desert vicinity

In this study, the hydrogeochemical program PHREEQC was used to determine the chemical speciation and mineral saturation indices (SIs) of groundwater in the vicinity of the proposed high-level nuclear waste repository at Yucca Mountain, Nevada (USA). In turn, these data were used to interpret the origin and recharge mode of groundwater, to elucidate the mechanisms of flow and transport, and to determine potential sources of groundwater contamination. PHREEQC was run to determine aqueous dissolved species and minerals that would be in equilibrium with the study area’s groundwater. Selected major ions, associated SI, F− and Ca/Na ion exchange were then examined using the multivariate statistical methods of principal component factor analysis and k-means cluster analysis. Analysis of dissolved ion concentrations, SIs, and Ca/Na ion exchange allows simultaneous consideration of arithmetic (raw concentrations) and logarithmic (SI, ion exchange) variables that describe the hydrochemical system and, therefore, can provide further insight into the system’s behavior. The analysis indicates that the dominant processes and reactions responsible for the hydrochemical evolution in the system are (1) evaporative concentration prior to infiltration, (2) carbonate equilibrium, (3) silicate weathering reactions, (4) limited mixing with saline water, (5) dissolution/precipitation of calcite, dolomite and fluorite, and (6) ion exchange. Principal component factor analysis and k-means cluster analysis of factor scores allow the reduction of dimensions describing the system and the identification of hydrogeochemical facies and the processes that defined and govern their evolution. Statistical analysis results indicate that the northern, west face and southern Yucca Mountain groundwater is fresh water with low concentrations of Ca2+, Mg2+, Cl−, Ca2+/(Na+)2, and CaF2. The Fortymile Wash groundwater is dilute. The carbonate signature is shown in the Ash Meadows and Death Valley waters with high fluorite SI. Finally, the Crater Flat, Stripped Hills, and Skeleton Hills are dominated by Ca/Na ion exchange, Mg and Ca. The hydrochemical and statistical analyses showed three main groundwater signatures or hydrochemical processes indicating groundwater evolution, potential flowpaths, and recharge areas. The flowpaths are the trace of the Amargosa River, the trace of Fortymile Wash, and its convergence with the Amargosa River. This appears to represent not just a groundwater flow path, but traces of surface runoff infiltration as well.

Syndromic Association of Behavioral and Psychological Symptoms of Dementia in Alzheimer Disease and Patient Classification

To identify patient groups with Alzheimer disease (AD) according to the presence of psychological and behavioral syndromes and to determine the clinical differences among these groups. Cross-sectional and observational study of 491 patients with probable AD whom were administered the Neuropsychiatric Inventory (NPI) at the baseline visit and reevaluated after 12 months. Principal component analysis (PCA) of baseline NPI data revealed three factors, including a psychosis factor (delusions, hallucinations, and aberrant motor behavior), a depressive factor (depression, anxiety, irritability, agitation, and apathy) and a hypomanic factor (euphoria and disinhibition). Cluster analysis of factor scores indicated the presence of three patient groups: one group was characterized by low scores in factors, a second group including patients with high scores in the depressive factor, and a third group that included patients with high scores in the three factors. The PCA of the NPI scores carried out after 1 year showed the persistence of the three factors. The cluster analysis of their factor scores also showed the presence of the same three patient groups but with a few differences in certain symptoms. A higher frequency of personal psychiatric history but no family history was observed in the cluster with depressive symptoms. Three neuropsychiatric syndromes have been identified, which have made it possible to classify patients with AD in three distinct large groups. A temporal stability is evidenced among the group with low symptoms. Patients with high scores in depressive factor or in three factors showed greater temporal instability. Certain differences among the groups suggest that different physiopathogenic mechanisms may be involved in neuropsychiatric syndromes.

3차원 인체형상자료를 이용한 겨드랑둘레선의 형태특성 및 유형

The purpose of this study was to examine the characteristics of armscye circumference which will be used to develop total contents for the apparel industry. The subjects of this study were 16- to 49-year-old women whose 3D body shape data were analyzed. 72 length and length-ratio measurements were taken to each subject' armscye circumference. The used analysis methods are descriptive statistics, principal component analysis, and cluster analysis. The results are follows; 1. Considering the Length of armscye circumference, the result of principal component analysis were extracted 3 factors and those factors comprised 95% of total variance. As the result of the cluster analysis of factor scores, subjects were classified into 4 cluster by their size characteristic. 2. Considering the length-ratio of armscye circumference, the result of principal component analysis were extracted 5 factors and those factors comprised 96.45% of total variance. As the result of the cluster analysis of factor scores, subjects were classified into 5 cluster by their shape characteristic. So that, this research could be useful to manufacture garment which reflected 3D body figure and improved fitting.

Understanding differences in trainee teachers' values and practice in relation to assessment

This study uses cluster analysis to examine groupings of trainee teachers against dimensions underpinning their values and practice in relation to assessment. Our sample comprised 220 trainees, studying for a Postgraduate Certificate in Education, an initial teacher training and education course, at the University of Cambridge, UK. The survey instrument derives from D. Pedder and M. James, and aimed to discover how trainee teachers value and implement different classroom assessment practices in their teaching. Cluster analysis of factor scores from varimax rotated principal components analysis revealed four clusters of trainees in relation to their practice responses, and two clusters in relation to values responses. Similarities and differences between clusters are discussed, as are similarities and differences with corresponding solutions for qualified teachers. Membership of clusters was found to be associated with membership of particular subject disciplines. The implications for initial teacher education and training are discussed.

Symptom patterns in late luteal-phase dysphoric disorder

The symptom patterns of 180 women with prospectively confirmed late luteal-phase dysphoric disorder (LLPDD) were examined using a careful application of factor and cluster analytic techniques. Factor analysis of premenstrual change scores on 33 common premenstrual syndrome symptoms yielded four orthogonal factors that were consistent across two sets of menstrual cycle data. These were a negative affect dimension with concomitant behavioral changes, physical symptoms, agitation, and positive arousal. Cluster analysis of factor scores grouped patients into one of five symptom patterns, the most common of which is a general distress cluster, characterized by symptoms across all dimensions. The LLPDD symptom groups identified are remarkably consistent with those of earlier studies using both normative and clinic samples, and consideration of symptom pattern differences in future research may greatly increase our understanding of this disorder.

Behavior Classification System for Children With Developmental, Psychiatric, and Chronic Medical Problems

Derived a new behavior classification system based on Missouri Children's Behavior Checklist (MCBC) ratings. Using an accumulated MCBC data base on 854 children, 4-14 years of age, with developmental disabilities (n = 471), psychiatric problems (n = 155), chronic illnesses (n = 184), and nonreferred controls (n = 44), raw scale scores were transformed into T scores and then factor analyzed. Three factors emerged: Internalizing, Externalizing, and Sociable. Hierarchical cluster analysis of factor scores yielded six behavior profile clusters that replicated. Classification rules, based on T scores, were derived for each of the six clusters and for unclassified profiles to yield seven behavior patterns. There were four behavior problem patterns: Internal, External, Mixed Internal and External profiles, and Undifferentiated Disturbance. There were three behavior problem free patterns: Low Social Skills, Problem-free, and Sociable profiles. The distribution of these seven behavior patterns differed significantly across children with developmental, psychiatric, and medical problems and nonreferred controls. Furthermore, the new system provides more refined behavior pattern delineation than previously developed systems.

Construct validity of the MacAndrew Scale: secondary psychopathic and dysthymic-neurotic character orientations among adolescent male misdemeanor offenders.

The empirical validity of the MacAndrew Scale was investigated in 200 adolescent males convicted of misdemeanor offenses who were classified according to their pattern of alcohol intoxication. Classification results were comparable to those from studies of adult men--true positive = 80%, false negative = 20%, true negative = 81% and false positive = 19%. An empirical cluster analysis of factor scores from the California Psychological Inventory yielded 14 personality types. About 56% of these cases resembled two character orientations (Emotional Extraversion or Emotional Introversion) that were hypothesized by MacAndrew to mediate addiction-proneness among males. However, 38.7% of these subjects were not alcohol misusers. The hypothesis that Emotional Introverts tend to be classified as false negatives was not supported--true positive = 79% and false negative = 21%. Although MacAndrew's formulation of two character orientations has heuristic value, the present study found alcohol misuse among adolescents with other personality characteristics. Studies of nonoffender adolescent males were recommended to clarify the MacAndrew Scale's sensitivity to the character orientation Emotional Introvert. Consistent with earlier research, the present study found no evidence of high levels of emotional tension in the form of anxiety or depression among adolescent alcohol misusers.

Post-Pleistocene Depositional Change at Rodgers Shelter, Missouri

Investigations of the deposits in Rodgers Shelter (23BE 125), on the western periphery of the Ozark Highlands, delineated major depositional patterns at the site and determined the chronological relationship of these patterns to human activities. Twenty-five sediment samples representing a stratigraphic sequence through the 11,000 year old accumulation were subjected to 2 types of analysis: 1) particle size determinations made by a combination of the hydrometer method and wet sieving, and 2) determination of mineral and rock composition of gravel and coarse sand by visual examinationPrincipal components factor analysis applied to particle size and composition data yielded 3 factors representing changing upland and hillslope erosional patterns, shifting location of the nearby Pomme de Terre River channel, and variations in vertical accretion by the Pomme de Terre River.Weighted average cluster analysis of factor scores on the 3 depositional variables delimited 7 major groups of samples, each representing distinctly different depositional conditions. Viewed stratigraphically, 10 depositional units were defined. The depositional environment of each was determined by mean factor scores. These stratigraphic units provide a more refined picture of site stratigraphy than is available from field observations alone.Viewed chronologically, the cluster analysis provides a model of the post-Pleistocene depositional history of the site: progressing from a period of intense upland erosion and aggradation by the Pomme de Terre, to a period of severe local hillslope erosion and valley degradation, and finally to a period of combined alluvial and colluvial deposition on the T-lb terrace. When the depositional history and cultural history of the site are compared, every major hypothesized change in human adaptive strategy coincides with a major change in depositional patterns, providing a convincing example of the close interrelationship between human behavior and surrounding environmental conditions