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The Impact of Disruptions on Routinization of Goal-Directed Grocery Shopping BehaviorOng, Adeline, Pek Kay, adeline.ong@rmit.edu.au January 2007 (has links)
This thesis bridges a gap in extant research by examining key factors that play a role in behavioral grocery shopping routines following minor and major disruptions. The present research involves two interrelated investigations incorporating mixed methodologies (Cresswell, 2003). Study 1 involves semi-structured in-depth interviews seeking to establish how goal-directed grocery shopping routines are developed over time. Utilizing a laddering approach of questioning (Gutman, 1997), respondents are probed on their routines (Brotherton, 2001) and goals, including end goals as described in the List of Values (Kahle & Kennedy, 1988). Three participants were interviewed on three occasions over an eight week period, until theoretical saturation was achieved. A significant contribution of Study 1 lies in the development of a conceptual framework for understanding factors associated with grocery shopping routines. This model reflects a working definition characterizing routines as goal-driven and value-guided heuristic strategies. It is proposed that routines are repetitive patterns of personal and private behavioral activities dependent upon situational and temporal contexts, and utilized for instrumental reasons. Risk-taking attitudes and personal values also shape goal-directed behaviors. Using structural equation modeling (SEM) procedures (Jöreskog & Sörbom, 1993), Study 2, an online experiment, aims to test and build upon the conceptual model emanating from Study 1. This study also investigates the impact of minor and major disruptions on routinized grocery shopping behavior. 612 participants were allocated across three experimental groups: situational contexts, anticipated temporal conditions, and repetitive value. Cohorts were assessed at baseline levels and received unique minor and major disruptions appropriate to their circumstance. Study 2 contributes through the large-scale SEM testing of a model of grocery shopping routinization. Overall, sound structural model fit demonstrates that the present model of grocery shopping routinization is explained by six distinct components including routinized behavior, goal-centeredness, situational contexts, anticipated temporal conditions, repetitive value, and risk-taking attitudes; and three dimensions of personal values: maturity, self-direction/achievement, and enjoyment. In terms of disruptions, findings indicate that routine strength is dependent on degree of situational, temporal, and instrumental interruptions. Disruptions can both facilitate and impede routines. Results demonstrate that regardless of goal stability, routines change when model components are disrupted. Findings suggest theoretical, research, and practical implications. This thesis expands decision making theory (Betsch, Fiedler, & Brinkmann, 1998) by demonstrating that, despite unwavering goals, new contexts arising from disruptions influence new behavioral deliberations. In relation to research implications, this thesis develops then subsequently tests a model of grocery shopping routinization. Despite routines becoming subconscious over time (Aarts & Dijksterhuis, 2000a), this study asserts that routines are intentional and involve goal-directed strategies for dealing with the environment. From an applied perspective, practitioners should be aware that routine-disrupted consumers remain goal-driven. Consumers are unlikely to forego focal goals (e.g., shop for weekly household meals) if these goals are non-negotiable. Present results suggest that consumers esteem maturity-related personal values, such as fostering and maintaining warm relationships with others and sense of belonging, when grocery sho pping.
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Using Structural Equation Modeling to study the relationship between the sea anemone Phymanthus strandesi and ecological factors in the seagrass bed of Hsiao-Liuchiu IslandChang, Chen-hao 30 August 2010 (has links)
Seagrass bed is a highly productivity ecosystem, it also provides habitats for animals and plays an important role in stabilizing the substrate. The sea anemone Phymanthus strandesi is very abundant in the seagrass bed of Thalassia hemprichii on Hsiao-Liuchiu Island. Structural Equation Modeling (SEM) was used to investigate the relationship between P. strandesi and some environmental factors, which affect the distribution of this species at Tuozaiping tidal flat (N 22¢X20"55' E 120¢X21"49'), Hsiao-Liuchiu Island. Light and temperature were also manipulated in the laboratory to test their effect on the hiding response of P. strandesi. The results of SEM show that the abundance of T. hemprichii showed very weak positive relation with P.strandesi. On the other hand, soil depth on the seagrass bed might be the main factor that affects the distribution of P. strandesi. In high a temperature situation (i.e. over 38¢XC), all the sea anemones in the experimental container hided into the sand.
However, only some sea anemones hid when exposed to strong light (i.e. 5030 lum/ft²) after one and half hours.
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noneWang, Ning-Ying 21 January 2002 (has links)
Abstract
The communication and information technology, particularly the Internet, has dramatically changed the way we have done business before. Therefore. Some different work arrangements have emerged in the technology-based business, such as telecommuting, mobile office, hoteling, satellite office, etc. The number of telecommuters in the US today is up to 25 million. In Taiwan, China Productivity Center (CPC), Taiwan Xerox, Taiwan IBM, and Taiwan HP have implemented the mobile office system for several years. Arthur Andersen and Sun also built their flexible office last year.
As the literatures indicated that telecommuting did increase organizational flexibility, job efficiency, employee satisfaction, productivity, customer satisfaction, while reduce commuting time and transportation costs, office spaces. However, the teleworkers felt more isolated as a result of working in a remote environment. Their interpersonal relationship and communication with supervisor or co-worker all got worse. Besides, managers also worried about telecommuting will reduce their authority and control power.
The main purpose of this study is to understand how Internet affect the individual worker¡¦s work style, especially what are the key factors being considered in telecommuting. Finally, the proposed telecommuting model would be empirically examined in the selected information technology-based organizations.
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A Monte Carlo Investigation of Three Different Estimation Methods in Multilevel Structural Equation Modeling Under Conditions of Data Nonnormality and Varied Sample SizesByrd, Jimmy 14 January 2010 (has links)
The purpose of the study was to examine multilevel regression models in the context of multilevel structural equation modeling (SEM) in terms of accuracy of parameter estimates, standard errors, and fit indices in normal and
nonnormal data under various sample sizes and differing estimators (maximum likelihood, generalized least squares, and weighted least squares). The finding revealed that the
regression coefficients were estimated with little to no bias among the study design conditions investigated. However, the number of clusters (group level) appeared to
have the greatest impact on bias among the parameter estimate standard errors at both level-1 and level-2. In small sample sizes (i.e., 300 and 500) the standard errors
were negatively biased. When the number of clusters was 30 and cluster size was held at 10, the level-1 standard errors were biased downward by approximately 20% for the
maximum likelihood and generalized least squares estimators, while the weighted least squares estimator produced level-1 standard errors that were negatively biased by 25%. Regarding the level-2 standard errors, the
level-2 standard errors were biased downward by
approximately 24% in nonnormal data, especially when the correlation among variables was fixed at .5 and kurtosis
was held constant at 7. In this same setting (30 clusters with cluster size fixed at 10), when kurtosis was fixed at 4 and the correlation among variables was held at .7, both the maximum likelihood and generalized least squares estimators resulted in standard errors that were biased downward by approximately 11%. Regarding fit statistics, negative bias was noted among each of the fit indices investigated when the number of clusters ranged from 30 to 50 and cluster size was fixed at 10. The least amount of bias was associated with the maximum likelihood estimator in each of the data normality
conditions examined. As sample size increased, bias decreased to near zero when the sample size was equal to or greater than 1,500 with similar results reported across
estimation methods. Recommendations for the substantive researcher are presented and areas of future research are presented.
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Bias and precision of parameter estimates in structural equation modeling and multiple regressionPerera, Robert A. January 2009 (has links)
Thesis (M.A.)--University of Notre Dame, 2009. / Thesis directed by Scott E. Maxwell for the Department of Psychology. "December 2009." Includes bibliographical references (leaves 70-72).
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Structural equation modeling compared with ordinary least squares in simulations and life insurers’ dataXiao, Xuan, active 2013 04 December 2013 (has links)
Structural equation model (SEM) is a general approach to analyze multivariate data. It is a relatively comprehensive model and combines useful characteristics from many statistical approaches, thus enjoys a variety of advantages when dealing complex relationships. This report gives a brief introduction to SEM, focusing especially the comparison of SEM and OLS regression. A simple tutorial of how to apply SEM is also included with the introduction and comparison. SEM can be roughly seen as OLS regression added with features such as simultaneous estimation, latent factors and autocorrelation. Therefore, SEM enjoys a variety of advantages over OLS regression. However, it is not always the case that SEM will be the optimal choice. The biggest concern is the complexity of SEM, for simpler model will be preferable for researchers when the fitness is similar. Two simulation cases, one requires special features of SEM and one satisfies assumptions of OLS regression, are applied to illustrate the choice between SEM and OLS regression. A study using data from US life insurers in the year 1994 serves as a further illustration. The conclusion is when special features of SEM is required, SEM fits better and will be the better choice, while when OLS regression assumptions are satisfied, SEM and OLS regression will fit equally well, considering the complexity of SEM, OLS regression will be the better choice. / text
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The nature of socioeconomic status among young adults, and its effect on health : a multi-group SEM analysis by gender and race/ethnicityYarnell, Lisa Marie 19 September 2011 (has links)
This dissertation focuses on results of multi-group SEM models estimated using data from the National Longitudinal Study of Adolescent Health (Add Health) in order to determine appropriate measurement and structural models for the relationship between socioeconomic status (SES) and health among six young adult U.S. social groups. Examining the links between SES and health during young adulthood is important because while there is a strong, documented link between lower SES and poorer health (Adler & Snibbe, 2003), young adults can exercise a considerable amount of agency with regard to their own SES and health. Young adults make critical decisions about pursuing post-secondary education, entering the workforce, and practicing healthy behaviors--activities which differ in their immediate and long-term economic and health payoff (Mirowsky & Ross, 2003; Elder, 1985; 1994). Yet, the nature of SES and its links with health for members of various gender and racial/ethnic groups is not entirely clear. Literature suggests that occupation, education, and income are neither defined nor linked among women in the same ways that they are for men
(APA, 2007). Self-assessment of health is also thought to differ by gender and ethnicity (Krause & Jay, 1994). Moreover, limited research has addressed the unique mediating pathways by which aspects of SES affect health for specific social groups (Matthews, Gallo, & Taylor, 2010). In this work, I estimate measurement models for several aspects of SES
among African American, Latina, and White men and women, then link aspects of SES with each other and with health using structural equation modeling. I also examine the unique mediating pathways by which aspects of SES are linked with health for these groups. / text
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The Integrative Neuropsychological Theory of Executive-Related Abilities and Component Transactions (INTERACT): a novel validation study.Frazer, Jeff 25 June 2012 (has links)
The Integrative Neuropsychological Theory of Executive-Related Abilities and Component Transactions (INTERACT; Garcia-Barrera, 2011) is a novel perspective on executive function(s), and the functional interactions among those neural systems thought to underlie them. INTERACT was examined in this validation study using structural equation modeling. A novel battery of computerized tasks was implemented in a sample of 218 healthy, adult, university students. Each of the derived indicator variables represented a specific aspect of performance, and corresponded with one of the five distinct executive components of INTERACT. After eliminating tasks that demonstrated poor psychometric properties, overall model fit was excellent, χ2 = 36.38, df = 44, p = .786; CFI = 1.00; RMSEA = .000. Further, INTERACT was superior to six alternative measurement models, which were theoretically-based. Although the structural model of INTERACT was too complex to be tested here, a novel analysis of the data was introduced to test the interactions among INTERACT’s components. This analysis demonstrated the significant utility of INTERACT’s fundamental theoretical predictions. Given the outcome of this initial validation study, the predictive power of INTERACT should continue to be exploited in future studies of executive function(s), and should be extended to explore executive systems in unique populations. / Graduate
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Genetic applications using structural equation modelingMi, Xiaojuan. January 2009 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed June 26, 2009). PDF text: vii, 120 p. : ill. ; 855 Kb. UMI publication number: AAT 3350451. Includes bibliographical references. Also available in microfilm and microfiche formats.
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Emotion Dysregulation and Psychopathology: A Structural Exploration of Emotional Factors and Positive and Negative Affect.Melka, Stephen Edward 01 August 2011 (has links)
Recent epidemiological data from the National Comorbidity Survey (NCS) estimate significant lifetime prevalence rates for anxiety and mood disorders, suggesting nearly one in three people would meet diagnostic criteria for an anxiety and/or mood disorder at some point during their lifetime (NCS, 2007). Comorbidity research has also revealed that people often suffer from these disorders concurrently (Rodriguez et al., 2004). Many have argued that anxiety and mood disorders frequently co-occur because they share similar etiological factors (Barlow, 1991; Clark & Watson, 1991; Watson, 2005). Additional empirical research has suggested that depressive and anxiety disorders share similar genetic diatheses and merely present differently because of variation in environmental stressors (Hettema, Neale, & Kendler, 2001; Rutter Moffit, & Caspi, 2006). As a result, an investigation of shared emotion regulation and affective processes across anxiety and mood disorders may reveal parallel etiological factors and areas for intervention. Research examining emotion and affective dysregulation indicates that mood and anxiety pathology may be characterized by similar emotional control and understanding deficits (Amstadter, 2008; Bradley, 2000; Sandin et al., 1996). Models of emotion dysregulation suggest that individuals suffering from anxiety pathology report decreased understanding of emotions, higher reactivity and sensitivity to emotions, and poor emotional management and mood repair skills (Mennin et al., 2005). Similarly, studies have observed parallel difficulties in those with depression (Liverant, Brown, Barlow, & Roemer, 2008; Rude and McCarthy, 2003). Additionally, research has indicated that efforts to reappraise or suppress emotions may affect the intensity and valence of emotional experiences (Gross & John, 2004). The current study builds off this research by incorporating elements of previous models of emotion dysregulation and anxiety and mood pathology in an effort to develop a comprehensive model of affective process that may underlie both anxious and depressive symptomatology. A total of 526 undergraduate students participated in the present investigation by completing a series of self-report instruments measuring affect and psychopathology. Response patterns were analyzed using AMOS 4.0 in order to examine the structural relationships between negative affectivity, positive affectivity, emotion reappraisal, emotion suppression, negative emotional reactivity, and poor understanding of emotions. Initial tests of a single model of emotion dysregulation suggested that the development of two separate models best represented subject responses. As a result, distinct models for suppression and reappraisal were tested concurrently. Tests of model invariance revealed similar structural qualities across gender, ethnicity, and levels of general distress for both models. Following modification, final fit indices suggested good fit for the reappraisal model (CFI = .99, TLI = .99, RMSEA = .057); however, the suppression model did not appear similarly representative of subject response behavior (CFI = .89, TLI = .85, RMSEA = .073). Findings of the current study suggest that the use of emotional reappraisal may be associated with increased positive affective and decreased negative affective states. Further, attempts to reappraise emotional experiences may influence the relationships poor understanding of emotions and fear of strong affect demonstrated with negative and positive affect. Data support previously articulated psychotherapy treatment strategies (Beck, 1979; Barlow & Cerny, 1988; Linehan, 1993; Hayes, 2004), but also indicate that current cognitive behavioral therapies may benefit from heightened attention to emotions and the incorporation of affective regulation skill building strategies. Future research directions, study strengths and limitations, and additional implications of present results are included.
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