33 resultados para Multiple correspondence analysis
Resumo:
Isotope signatures of mangrove leaves can vary depending on discrimination associated with plant response to environmental stressors defined by gradients of resources (such as water and nutrient limitation) and regulators (such as salinity and sulfide toxicity). We tested the variability of mangrove isotopic signatures (d13C and d15N) across a stress gradient in south Florida, using green leaves from four mangrove species collected at six sites. Mangroves across the landscape studied are stressed by resource and regulator gradients represented by limited phosphorus concentrations combined with high sulfide concentrations, respectively. Foliar d13C ratios exhibited a range from 24.6 to –32.7‰, and multiple regression analysis showed that 46% of the variability in mangrove d13C composition could be explained by the differences in dissolved inorganic nitrogen, soluble reactive phosphorus, and sulfide porewater concentrations. 15N discrimination in mangrove species ranged from –0.1 to 7.7‰, and porewater N, salinity, and leaf N:Pa ratios accounted for 41% of this variability in mangrove leaves. The increase in soil P availability reduced 15N discrimination due to higher N demand. Scrub mangroves (<1.5 m tall) are more water-use efficient, as indicated by higher d13C; and have greater nutrient use efficiency ratios of P than do tall mangroves (5 to 10 m tall) existing in sites with greater soil P concentrations. The high variability of mangrove d13C and d15N across these resource and regulator gradients could be a confounding factor obscuring the linkages between mangrove wetlands and estuarine food webs. These results support the hypothesis that landscape factors may control mangrove structure and function, so that nutrient biogeochemistry and mangrove-based food webs in adjacent estuaries should account for watershed-specific organic inputs.
Resumo:
Eating disorders can lead to a negative impact on students' academic growth, nutrition and can cause death (Claude-Pierre, 1997; Manley, Rickson, & Standeven, 2000; Romeo, 1996). Early intervention by referring students to professional counseling might help counter these negative consequences. The teacher is in the position to assist students by providing health information, identifying those with problems, and intervening for a variety of dysfunctions that may include the eating disorders called anorexia nervosa and bulimia nervosa (Myers-Clark & Christopher, 2000). However teachers are in a difficult position to know when to address student concerns and judge what action to take (Ransley, 1999). Teachers' engagement seems crucial (Smolak, Harris, Levine, & Shisslak, 2001) since eating disorders are being identified in younger children. The purpose of this study was to examine (a) the relationships of the theoretical constructs, attitude, subjective norm, and perceived behavioral control of the theory of planned behavior as predictors of behavioral intention (Ajzen & Fishbein, 1980) of middle school teachers to identify and refer suspected anorexia nervosa (AN) and/or bulimia nervosa (BN) students for professional help; and (b) the actual behavior of middle school teachers who reported having ever referred a student suspected of having AN and BN and those teachers who reported not having made such a referral. One hundred fourteen middle school teachers in Broward County, Florida volunteered to participate in the ex post facto research. Data were collected from a questionnaire. Multiple regression analysis revealed that the constructs of subjective norm (perception of what others think about one's performance of behavior combined with motivation to comply) and perceived behavioral control (perception regarding the extent of the difficulty of performing the behavior) were predictive of teachers' intent (likelihood of engaging in a behavior) to refer. However, the analysis revealed that attitude (overall positive or negative feeling with respect to performing the behavior) was not predictive of teachers' intent. Discriminant function analysis revealed that both intent and perceived behavioral control were predictive of group membership, either having referred a student suspected of having an eating disorder for counseling or not having made such a referral. Attitude and subjective norm were not predictive of group membership.
Resumo:
In the Everglades, the majority of fish detrital inputs occur during the dry scason, when waterlevel drawdown reduces aquatic habitat. While these mortality events are highly seasonal, the remineralization and recycling of fish detrital nutrients may represent an important stimulus to the ecosystem in the following wet season. The goal of this study was to quantify the rate of detrital fish decomposition during three periods of the year to determine seasonal variations in decomposition patterns in this ecosystem. A multiple regression analysis showed that hydroperiod and water depth both played a role in determining fish decomposition rates within this ecosystem. Decomposition rates ranged from a low of 13% day−1 in December 2000 to a high of 50% day−1 in April 2001, the height of the dry season. Phosphorus analysis showed that Gambusia holbrooki, the dominant small fish species in the Everglades, contains 7.169±1.46 mg P g−1 wet fish weight. Based on the observed decomposition rates and the average biomass added, the estimafed daily flux of phosphorus from the experimental detrital loading ranged from a low of 27.04 mg P day−1 to a high of 108.14 mg P day−1 during the decomposition period. We estimated that these inputs could represent an input of 43 μg P m−2 day−1 to the total temporal Everglades phosphorus budget. Although much of this phosphorus is likely incorporated into the macroinvertebrate pool, detrital inputs peak during the dry season when nutrients are most likely to be incorporated into the soil and occur when decomposition of vegetative material is moisture-limited. These inputs may therefore play an important role in stimulating vegetative production during the early wet season.
Resumo:
The purpose of this study is to investigate supervisory support as a moderator of the effects of role conflict and role ambiguity on emotional exhaustion and job satisfaction. This study also examines the moderating role of supervisory support on the relationship between emotional exhaustion and job satisfaction. Data were collected from a sample of frontline hotel employees in Northern Cyprus. The aforementioned relationships were tested based on hierarchical multiple regression analysis. The results demonstrate that supervisory support mitigates the impact of role conflict on emotional exhaustion and further reveal that supervisory support reduces the effect of emotional exhaustion on job satisfaction. There is no empirical support for the rest of the hypothesized relationships. Implications of the empirical results are discussed, and future research directions are offered.
Resumo:
One in five adults 65 years and older has diabetes. Coping with diabetes is a lifelong task, and much of the responsibility for managing the disease falls upon the individual. Reports of non-adherence to recommended treatments are high. Understanding the additive impact of diabetes on quality of life issues is important. The purpose of this study was to investigate the quality of life and diabetes self-management behaviors in ethnically diverse older adults with type 2 diabetes. The SF-12v2 was used to measure physical and mental health quality of life. Scores were compared to general, age sub-groups, and diabetes-specific norms. The Transtheoretical Model (TTM) was applied to assess perceived versus actual behavior for three diabetes self-management tasks: dietary management, medication management, and blood glucose self-monitoring. Dietary intake and hemoglobin A1c values were measured as outcome variables. Utilizing a cross-sectional research design, participants were recruited from Elderly Nutrition Program congregate meal sites (n = 148, mean age 75). ^ Results showed that mean scores of the SF-12v2 were significantly lower in the study sample than the general norms for physical health (p < .001), mental health (p < .01), age sub-group norms (p < .05), and diabetes-specific norms for physical health (p < .001). A multiple regression analysis found that adherence to an exercise plan was significantly associated with better physical health (p < .001). Transtheoretical Model multiple regression analyses explained 68% of the variance for % Kcal from fat, 41% for fiber, 70% for % Kcal from carbohydrate, and 7% for hemoglobin A 1c values. Significant associations were found between TTM stage of change and dietary fiber intake (p < .01). Other significant associations related to diet included gender (p < .01), ethnicity (p < .05), employment (p < .05), type of insurance (p < .05), adherence to an exercise plan (p < .05), number of doctor visits/year ( p < .01), and physical health (p < .05). Significant associations were found between hemoglobin A1c values and age ( p < .05), being non-Hispanic Black (p < .01), income (p < .01), and eye problems (p < .05). ^ The study highlights the importance of the beneficial effects of exercise on quality of life issues. Furthermore, application of the Transtheoretical Model in conjunction with an assessment of dietary intake may be valuable in helping individuals make lifestyle changes. ^
Resumo:
Increased treatment retention among substance abusing individuals has been associated with reduced drug use, fewer arrests, and decreased unemployment, as well as a reduction in health risk behaviors. This longitudinal study examined the predictors of client retention for alternative to prison substance abuse treatment programs through assessing the roles of motivational factors and the client-worker relationship. The sample was comprised of 141 male felony offenders who were legally mandated to community based long-term residential drug treatment programs. ^ The primary measures used in the study were the consecutive days a participant remained in treatment, Stages of Change Readiness Model and Treatment Eagerness Scale (SOCRATES), the Working Alliance Inventory (WAI), and The Readiness Ruler. Hierarchical multiple regression analysis was conducted for four hypotheses (a) participants who are more motivated to change at the time of entry will remain in treatment longer, (b) participants who have a strong therapeutic alliance will remain in treatment a greater number of consecutive days than participants who have weaker therapeutic alliance, (c) motivation to change, as measured at treatment entry, will be positively related to therapeutic alliance, (d) during the course of treatment variation in motivation to change will be predicted by the therapeutic alliance. ^ Results support the following conclusions: Among clients in alternative-to prison programs the number of days in treatment is positively related to their motivation to change. The therapeutic alliance is not a predictor of the number of days in treatment. Motivation to change, particularly recognition of a drug problem, is positively related to the therapeutic alliance. Changes in motivation to change in response to treatment are positively related to the therapeutic alliance among clients in an alternative to prison substance abuse treatment programs. These results carry forward prior research and have implications for social work practice, research, and social welfare policy. ^
Resumo:
The role of spirituality in leadership in business and other organizations has gained growing recognition. The purpose of this study was to explore the relationship between spirituality and nine selected transformational leadership practices. Community leaders (N = 138) in business, education, and other professions who were graduates of a 10-week leadership program, Leadership Fort Lauderdale, from 1994 to 2004 completed the Spirituality Assessment Scale (SAS), the Leadership Practices Inventory (LPI), and four transformational leadership items of the Multifactor Leadership Questionnaire (MLQ). ^ The predictor variables were participants' scores on the LPI and MLQ. The criterion variable was their score on the SAS. Stepwise multiple regression analysis was used to test the hypothesis: Is there a combination of nine selected transformational leadership practices that would account for a significant portion of the variance of each of two spirituality measures? The Definitive and Correlated dimensions and Total spirituality score of the SAS were used in the analysis. ^ Results showed that two of the LPI leadership practices were significantly related to spirituality. The variable Inspiring a Shared Vision accounted for 10% of the variance of the SAS Definitive dimension. The variable Encouraging the Heart accounted for 30% of the variance of the Correlated dimension. For the Total spirituality score, two models were revealed. In the first model, Encouraging the Heart accounted for 28% of the variance of the total spirituality score. In the second model, Encouraging the Heart and Inspiring a Shared Vision together accounted for 31% of the total spirituality score. None of the transformational leadership practices from the MLQ were significantly related to spirituality. ^ The data partially support the hypothesis: two of the nine leadership variables did in combination correlate with leaders' spirituality. The results also support at least a partial relationship between spirituality and certain transformational leadership practices among leaders in various spheres, such as education, business, and other professions. ^
Resumo:
The purpose of this study was to assess the relationship between working professionals' Career Decision-Making Self-Efficacy beliefs (CDMSE beliefs) and their reasons for participating in in-service master's level programs in Taiwan. ^ The data collection instruments used were Grotelueschen's (1985) Participation Reasons Scale (PRS), and Betz, Klein, and Taylor's (1996) Career Decision-Making Self-Efficacy-Short Form (CDMSE-SF), and a Demographic Data Form (DDF) developed specifically for this study. ^ Surveys were administered to 800 working professionals who participated in inservice master's level programs at 22 Taiwanese universities. The survey was conducted in May 2004. Data were analyzed by simple descriptive statistics, principal component factor analysis, and multiple regression. Four factors of participation reasons were found and five components of CDMSE beliefs were scored. ^ Five components of CDMSE beliefs are structured into the CDMSE-SF instrument: Self-Appraisal, Occupational Information, Goal-Selection, Planning, and Problem Solving. The reasons for participation found in this study were: Professional Improvement and Development, Professional Service, Personal Benefit and Job Security, and Professional Competence and Collegial Interaction. Pearson-product moment correlations revealed significant positive correlations between the five CDMSE subscales and the four factors of participation reasons. Multiple regression analysis revealed that participants' beliefs in their abilities to obtain information about occupations accounted for the preponderance of variance of scores on the Participation Reasons Scale (PRS). ^ This study concluded that professionals who believed that they were efficacious in obtaining information about occupations or professions tended to believe that the four reasons for participation represented by the factors of the PRS were important to them in making the decision to participate in continuing education. Additionally, it was noted that the reasons for participations for professionals who did not feel confident in their abilities to find such information could not be determined. ^ Recommendations are offered to assist those individuals responsible for developing recruiting programs in continuing education for professionals in Taiwan. These recommendations focus only on strategies intended to attract this target population of professionals who believe that they are efficacious in obtaining information about occupations. ^
Resumo:
In the mid 19th century, Horace Mann insisted that a broad provision of public schooling should take precedence over the liberal education of an elite group. In that regard, his generation constructed a state sponsored common schooling enterprise to educate the masses. More than 100 years later, the institution of public schooling fails to maintain an image fully representative of the ideals of equity and inclusion. Critical theory in educational thought associates the dominant practice of functional schooling with maintenance of the status quo, an unequal distribution of financial, political, and social resources. This study examined the empirical basis for the association of public schooling with the status quo using the most recent and comparable cross-country income inequality data. Multiple regression analysis evaluated the possible relationship between national income inequality change over the period 1985-2005 and variables representative of national measures of education supply in the prior decade. The estimated model of income inequality development attempted to quantify the relationship between education supply factors and subsequent income inequality developments by controlling for economic, demographic, and exogenous factors. The sample included all nations with comparable income inequality data over the measurement period, N = 56. Does public school supply affect national income distribution? The estimated model suggested that an increase in the average years of schooling among the population age 15 years or older, measured over the period 1975-1985, provided a mechanism that resulted in a more equal distribution of income over the period 1985-2005 among low and lower-middle income nations. The model also suggested that income inequality increased less or decreased more in smaller economies and when the percentage of the population age < 15 years grew more slowly over the period 1985-2000. In contrast, this study identified no significant relationship between school supply changes measured over prior periods and income inequality development over the period 1985-2005 among upper-middle and high income nations.
Resumo:
This study examined differences in cultural competency levels between undergraduate and graduate nursing students (age, ethnicity, gender, language at home, education level, program standing, program track, diversity encounters, and previous diversity training). Participants were 83% women, aged 20 to 62; 50% Hispanic/Latino; with a Bachelor of Science in Nursing (n = 82) and a Master of Science in Nursing (n = 62). Degrees included high school diplomas, associate/diplomas, bachelors' degrees in or out of nursing, and medical doctorate degrees from outside the United States. Students spoke English (n = 82) or Spanish ( n = 54). The study used a cross-sectional design guided by the three-dimensional cultural competency model. The Cultural Competency Assessment (CCA) tool is composed of two subscales: Cultural Awareness and Sensitivity (CAS) and Culturally Competent Behaviors (CCB). Multiple regressions, Pearson's correlations, and ANOVAs determined relationships and differences among undergraduate and graduate students. Findings showed significant differences between undergraduate and graduate nursing students in CAS, p <.016. Students of Hispanic/White/European ethnicity scored higher on the CAS, while White/non-Hispanic students scored lower on the CAS, p < .05. One-way ANOVAs revealed cultural competency differences by program standing (grade-point averages), and by program tracks, between Master of Science in Nursing Advanced Registered Nurse Practitioners and both Traditional Bachelor of Science in Nursing and Registered Nurse-Bachelor of Science in Nursing. Univariate analysis revealed that higher cultural competency was associated with having previous diversity training and participation in diversity training as continuing education. After controlling for all predictors, multiple regression analysis found program level, program standing, and diversity training explained a significant amount of variance in overall cultural competency (p = .027; R2 = .18). Continuing education is crucial in achieving students' cultural competency. Previous diversity training, graduate education, and higher grade-point average were correlated with higher cultural competency levels. However, increased diversity encounters were not associated with higher cultural competency levels.^
Resumo:
In this study, I divided samples from individuals within Afghanistan based upon geography (i.e., north versus south). I determined allelic frequencies and other statistical parameters for 15 STR loci (i.e., D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, Dl3S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA). I conducted pairwise comparisons with 19 neighboring Eurasian populations to assign Gstatistics and p-values. Categorizing the populations into five groups (i.e., Central Asia, East Asia, South Asia, the Middle East, and the Caucasus/Anatolia), I derived values for intra-population, inter-population, and total variance. Admixture analyses determined the highest allelic contributions to be from the Caucasus/ Anatolia, while negligible contributions were made by Central Asia and East Asia. A Correspondence Analysis revealed clustering of both northern and southern Afghanistan with Georgia, Turkey, northern Iran, and southern Iran of the Caucasus/ Anatolia and the Middle East. A Neighbor-Joining phylogenetic tree was constructed to generate bootstrap values over 1, 000 reiterations.
Resumo:
Using multiple regression analysis, lodging managers’ annual mean salaries in 143 Metropolitan Statistical Areas (MSA) within the U.S. were analyzed to identify what relationships existed with variables related to general MSA characteristics, along with the lodging industry’s size and performance. By examining the relationship between these variables, the authors predict the long-term possibility of predicting lodging industry managers’ salaries. These predictions may have an impact on financial performance of an individual lodging property or organization. Through this paper, this concept was applied and explored within U.S. MSAs. These findings may have value for a variety of stakeholders, including human resources practitioners, the hospitality education community, and individuals considering lodging management careers.
Resumo:
Multiple linear regression model plays a key role in statistical inference and it has extensive applications in business, environmental, physical and social sciences. Multicollinearity has been a considerable problem in multiple regression analysis. When the regressor variables are multicollinear, it becomes difficult to make precise statistical inferences about the regression coefficients. There are some statistical methods that can be used, which are discussed in this thesis are ridge regression, Liu, two parameter biased and LASSO estimators. Firstly, an analytical comparison on the basis of risk was made among ridge, Liu and LASSO estimators under orthonormal regression model. I found that LASSO dominates least squares, ridge and Liu estimators over a significant portion of the parameter space for large dimension. Secondly, a simulation study was conducted to compare performance of ridge, Liu and two parameter biased estimator by their mean squared error criterion. I found that two parameter biased estimator performs better than its corresponding ridge regression estimator. Overall, Liu estimator performs better than both ridge and two parameter biased estimator.
Resumo:
Increased treatment retention among substance abusing individuals has been associated with reduced drug use, fewer arrests, and decreased unemployment, as well as a reduction in health risk behaviors. This longitudinal study examined the predictors of client retention for alternative to prison substance abuse treatment programs through assessing the roles of motivational factors and the client-worker relationship. The sample was comprised of 141 male felony offenders who were legally mandated to community based long-term residential drug treatment programs. The primary measures used in the study were the consecutive days a participant remained in treatment, Stages of Change Readiness Model and Treatment Eagerness Scale (SOCRATES), the Working Alliance Inventory (WAI), and The Readiness Ruler. Hierarchical multiple regression analysis was conducted for four hypotheses (a) participants who are more motivated to change at the time of entry will remain in treatment longer, (b) participants who have a strong therapeutic alliance will remain in treatment a greater number of consecutive days than participants who have weaker therapeutic alliance, (c) motivation to change, as measured at treatment entry, will be positively related to therapeutic alliance, (d) during the course of treatment variation in motivation to change will be predicted by the therapeutic alliance. Results support the following conclusions: Among clients in alternative-to prison programs the number of days in treatment is positively related to their motivation to change. The therapeutic alliance is not a predictor of the number of days in treatment. Motivation to change, particularly recognition of a drug problem, is positively related to the therapeutic alliance. Changes in motivation to change in response to treatment are positively related to the therapeutic alliance among clients in an alternative to prison substance abuse treatment programs. These results carry forward prior research and have implications for social work practice, research, and social welfare policy.
Resumo:
The main research objective of this study was to find out whether perceived value significantly affects consumers’ purchase intention. Additionally, this study examined if there are any significant differences in perceived value for different fast-food restaurant brands and attempted to identify which fast-food restaurant is perceived to be the industry leader. A total number of six fast-food restaurants (McDonalds, Subway, Starbucks, Wendy’s, Burger King, and Taco Bell) were selected. Findings showed that among the five perceived service value dimensions, Starbucks is the leader in terms of quality, emotional response, and reputation. Multivariate analysis of variance (MANOVA) and multiple regression analysis were performed to test the study hypotheses. Results indicated that there were significant differences in perceived value for different fast-food restaurant brands. Besides, monetary and behavioral price significantly affects consumers’ purchase intention. Findings are expected to help hospitality marketers to strategically manage their brands.