Logistic Regressions

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Logistic regression applied to natural hazards: rare event logistic regression with replications

Logistic regression applied to natural hazards: rare event logistic regression with replications

Potential anthropogenic and biophysical explanatory vari- ables of landslide occurrence have been selected based on lit- erature and data availability. The following explanatory vari- ables were included in the analyses: slope, distance to water- course, distance to path, curvature and different trajectories of land cover change. The first three variables are quantita- tive, while the two last ones are qualitative variables com- posed of respectively three and five classes (Table 1). All our data are spaced in maps in a grid-cell mapping unit, as it is very common nowadays with GIS utilisation (Guzzetti et al., 1999). The GIS grid-data has been transformed into a matrix format: an attribute table in which the lines corre- spond with the 20 m resolution pixels of the catchment and the columns with the 11 potential explanatory variables. A similar attribute table was made for the landslide invento- ries. In order to avoid auto-correlation, we represented every landslide by one grid-cell (pixel) located in the centre of the shear plane. For the logistic regressions, one matrix was es- tablished including the matrix of GIS grid-data and spatial in- formation on the observed landslide occurrence in the catch- ment. For all grid-cells, the value of a dichotomous depen- dent variable landslide indicates the presence (landslide = 1) or absence (landslide = 0) of a landslide. The matrices were imported in R software for the probabilistic and statistical analyses.

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Cognitive impairment and dependence of patients with diabetes older than 65 years old in an urban area (DERIVA study)

Cognitive impairment and dependence of patients with diabetes older than 65 years old in an urban area (DERIVA study)

Results: Nearly one quarter of patients with diabetes (21.7 %) lived alone. Diabetic patients were more sedentary ( p = .033) than non-diabetic patients. Roughly one sixth (15.3 %) of the diabetics and 10.1 % of the non-diabetics were depressed ( p = .332). CI was present in 26.1 % of the diabetics and 14.5 % of non-diabetics ( p = .029). Diabetic patients had a MMSE score that was significantly worse than non-diabetics (24.88 ± 4.74 vs 26.05 ± 4.03; p <.05), but no differences were found in the Seven Minute Screen Test. Logistic regressions revealed that the presence of diabetes was independently associated with CI (adjusted for age, gender, years of education, sedentary lifestyle, body mass index, diastolic blood pressure, cholesterol, and depression (OR = 2.940, p = .013). Patients with diabetes showed greater dependence, as measured by the Barthel Index ( p = .03) and Lawton-Brody Index ( p <.01). Nevertheless, when dependence (dependence or not dependence for each questionnaire) used as a dependent variable in the logistic regression analyses, no significant association with diabetes was found, after adjusting for confounding variables.

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The effect of web based depression interventions on self reported help seeking: randomised controlled trial [ISRCTN77824516]

The effect of web based depression interventions on self reported help seeking: randomised controlled trial [ISRCTN77824516]

The first set of analyses addressed the question of whether the interventions were associated with reports of help seeking. It consisted of a series of separate logistic regres- sions assessing the impact of BluePages compared to the control condition, and BluePages compared to the MoodGYM site on help seeking for each of the specific treatments used (e.g., antidepressant medication). A sec- ond analysis assessed the effect of these the two interven- tions and the control condition on help seeking from different sources of help (professionals/family). A further set of four linear regressions examined whether those in the BluePages intervention compared to the two other interventions used different categories of treatments. BluePages was selected as the comparison condition in preference to the control condition because we hypothe- sized it would lead to greater help seeking for evidence- based treatments than the other two conditions. Supple- mentary analyses addressed the question of whether the reported seeking of help from a specific treatment or source was associated with a reduction in depressive symptoms. Separate linear regressions were used to exam- ine the reported use of each specific treatment and its association with depression (CES-D scores) at post inter- vention and at six months. A further four linear regres- sions examined whether the category types of treatment predicted depression. A second set of supplementary anal- yses investigated the relationship between the severity of depression and the reported uptake of specific treatments or sources, controlling for intervention type. A series of separate logistic regressions were used to assess the effect of the severity of depression (CES-D scores) at pre-inter- vention on the use of each treatment. Four linear regres- sions were used to examine the impact of depression on the number of every day, complementary, dietary and professional treatments used. No formal adjustment was undertaken for the number of comparisons that were tested. However, the majority of effects reported would remain significant even if correct using a extremely con- servative approach such as the Bonferroni method. Never- theless, the possibility of inflated Type I error arising from evaluating multiple treatments should be borne in mind. Results

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Exploring survival rates of companies in the UK video-games industry: An empirical study

Exploring survival rates of companies in the UK video-games industry: An empirical study

The study presented in this paper investigates companies operating in the UK video- game industry with regard to their levels of survivability. Using a unique dataset of companies founded between 2009 and 2014, and combining elements and theories from the fields of Organisational Ecology and Industrial Organisation, the authors develop a set of hierarchical logistic regressions to explore and examine the effects of a range of variables such as industry concentration, market size and density on companies' survival rates. The analysis addresses locational dimension of the video- game industry is considered by introducing an extra regionally-related variable into the models, associated with the number of video-game university programmes locally available. In addition, companies are investigated with regard to their organisational type in order to identify potential effects associated with their intrinsic organisational structures. Findings from the analysis confirm that UK video-game companies operate in an increasingly globalised market, limiting the effects related to any operation conducted at a local level. For instance, a higher supply of specialised graduates within spatial proximity does not contribute significantly to increase the chances of survivability of video-game companies, although different locations seemto provide better conditions and higher life expectancy, mainly due to positive network effects occurring at a local level. Results seemalso to suggest that investing in managerial resources increases businesses' survival rates, corroborating evidence about the significant role entrepreneurs have for companies operating within innovative and technologically intensive industries.

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Factors affecting habitat selection by Mrs Hume’s Pheasant Syrmaticus humiae (Hume, 1881) in Mizoram, northeast India

Factors affecting habitat selection by Mrs Hume’s Pheasant Syrmaticus humiae (Hume, 1881) in Mizoram, northeast India

Mrs Hume’s Pheasant Syrmaticus humiae (Hume, 1881) is a globally near-threatened pheasant spe- cies. It is sparsely distributed in eastern part of Mizoram, northeast India. The factors that influ- enced the habitat selection of S. humiae in the tropical montane forest are studied during January 2013 to March 2015. Based on preliminary survey a possible site of occurrence of the species was identified in the community reserved forest (CRF) adjacent to Lengteng Wildlife Sanctuary (LWS), near Myanmar border. Line transects were laid on two separate sites to determine the habitat use by the species. Physical variables were recorded on each transect sampling site. Only eight sight- ings are recorded at the Pine dominated area having good ground cover of tall grasses. The data analysis by principal component analysis (PCA) and stepwise logistic regressions analysis showed that litter cover and temperature plays a significant role (p<0.05) in the habitat selection by S.

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Organization of Hospital Nursing and Readmissions in Surgical Medicare Patients

Organization of Hospital Nursing and Readmissions in Surgical Medicare Patients

Hospital readmissions are prevalent and costly, particularly among older adults. They have been targeted as a field for improving the quality of care and reducing healthcare cost. Nursing is a critical factor in determining the quality of patient care. Despite increasing evidence linking nursing to various patient outcomes; there is an absence of research examining the nursing-readmission relationship. The purpose of this study is to identify the association between organization of hospital nursing and readmissions in surgical Medicare patients. Three organizational features of hospital nursing were studied, nurse work environment, nurse staffing, and nurse education. A secondary analysis was completed using a multi-state nurse survey, Medicare patient discharge data, and American Hospital Association annual survey, collected in 2006-2007. A sample of 220,914 Medicare patients and 23,090 nurses from 528 hospitals in four states (CA, FL, NJ, and PA) were analyzed. Survey responses from the study nurses were used to construct the hospital level measures of nurse work environment, patient-to-nurse ratio, and nurse education preparation. The outcome of interest was 30-day readmissions. Cross-tabulations examined readmissions by patient, hospital, and nursing characteristics. Multivariate logistic regressions estimated the effects of work environment, nurse

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13C-Urea breath test threshold calculation and evaluation for the detection of Helicobacter pylori infection in children

13C-Urea breath test threshold calculation and evaluation for the detection of Helicobacter pylori infection in children

Analyses and graphics were produced with S-Plus4.5 (MathSoft, Seattle) and SAS6.12 (SAS Institute, Cary). Ro- bust statistics included the median and the rescaled medi- an absolute deviation, which compare to mean and standard deviation. Natural logarithms of ∆δ values were used throughout. In histograms, the bin width was chosen by data-based kernel smoothing [19] and the bin height was scaled to a unit area under the curve [[20], p.168]. Logistic regressions of the histological detection of H. py- lori (positive or negative) on the ∆δ values were per- formed in randomly chosen 50% of the data. The resulting threshold ∆δ values were evaluated in the com- plementary 50% of the data on the basis of the observed H. pylori detection rate. Coefficients of determination (R 2 ) were obtained according to [21].

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How Does Incarcerating Young People Affect Their Adult Health Outcomes?

How Does Incarcerating Young People Affect Their Adult Health Outcomes?

compare covariates and adult health outcomes between individuals with a history of incarceration and those without any incarceration. Multivariate logistic regressions investigated the relationship between an individual’s cumulative duration of incarceration before Wave IV (age 24–34 years) and subsequent adult health outcomes (self-reported general health, functional limitations, depressive symptoms, and suicidal thoughts) in Wave IV, controlled for the covariates described above. We conducted analyses in Stata version 12.0 (Stata Corp, College Station, TX) using the “svy” suite of commands to account for the Add Health survey design elements of stratification, clustering, and weighting. We tested for interactions by gender and race/ ethnicity by creating interaction terms and by exploring analyses stratified by gender and race/ ethnicity. The study was approved by the UCLA institutional review board.

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Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses

The logistic regression approach does not extend easily to accommodate a time-varying exposure with a time-varying association with the outcome. A non-time- varying association between a time-varying exposure and an outcome can be estimated using logistic regres- sion by fitting separate models within a series of time periods, using current values of the time-varying expos- ure in each period, and pooling the estimates across pe- riods. This gives similar results to Cox regression using time-varying exposures [16]. This approach could be ex- tended to the setting of a time-varying exposure with a time-varying exposure-outcome association, by fitting logistic regressions within sub-intervals of each time period of interest for the time-varying association and obtaining a pooled estimate across sub-intervals within each time period, using current values of the time- varying exposure in each regression. However, this is cumbersome and requires sufficient numbers of cases and controls within sub-intervals. Therefore we con- sider the logistic regression approach to be impractical for time-varying exposures with a time-varying associ- ation with the outcome.

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Nosrati et al - 2017 - Ethnicity and place- the geography of diabetes inequalities under a strong welfare state published version.pdfView Download

Nosrati et al - 2017 - Ethnicity and place- the geography of diabetes inequalities under a strong welfare state published version.pdfView Download

Based on the empirical analyses provided in this article, the following may thus be said about inequalities in diabetes in Oslo, Norway. First, the findings reveal a distinct sociospatial pattern: diabetes tends to cluster in the historically disadvantaged eastern regions of the city with high proportions of inhabitants with non- Western ethnic origins. In addition, the logistic regression without random effects showed that, even when adjusting for a range of covariates (such as ethnicity, age or BMI), the residential location of individuals is a strong and highly significant predictor of diabetes. Second, it appears that the well-established association between ethnicity and diabetes is partly mediated by sociospatial context: the multilevel logistic regressions suggested that whilst ethnicity does exert a strong independent effect on diabetes outcome, its overall importance may nevertheless be said to depend on the broader sociospatial situation in which groups and individuals live their everyday lives. Put differently, the relationship between ethnicity and diabetes is at least partly confounded with environmental setting. Third, it was revealed that neighbourhood characteristics might play an important role in the making of diabetes inequalities. Insofar as living in a toxic environment and subjectively perceiving one’s food environment as inadequate increase the probability of suffering from diabetes, it is crucial to take the interaction between individual and group-level attributes into account when investigating health inequalities. Hence, the historically rooted and socially reinforced bisection between ‘East’ and ‘West’ is an agent of (re)production of diabetes inequalities in Oslo and must therefore be taken into consideration in future epidemiological research on health disparities under Norwegian capitalism.

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Suicide precipitants differ across the lifespan but are not significant in predicting medically severe attempts

Suicide precipitants differ across the lifespan but are not significant in predicting medically severe attempts

The data were analyzed using IBM SPSS Statistics 23 (IBM, Armonk, NY, USA). A series of six Chi-square test of independence was conducted to examine the association between age groups (Adolescence, Early Adulthood, and Middle Adulthood) with suicide precipitants (i.e., work, family, relationship, financial, and medical problems) and the medical severity of suicide attempts. Due to the number of analyses conducted, the alpha level was controlled, using Bonferroni adjustment (i.e., adjusted alpha = 0.05/6 analyses = 0.008). Subsequently, three direct logistic regressions were performed, one for each age group (Adolescence, Early Adulthood, and Middle Adulthood), to assess the effects of work, family, relationship, financial, and medical problems on the likelihood that participants attempted medically severe suicide attempts.

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Short Nighttime Sleep-Duration and Hyperactivity Trajectories in Early Childhood

Short Nighttime Sleep-Duration and Hyperactivity Trajectories in Early Childhood

tutes of Health Research (to Dr Touchette). Funding was also obtained from Quebec’s Department of Health and Social Services (Quebec City, Que- bec, Canada), the Canadian Institutes of Health Research (Ottawa, Ontario, Canada), the Social Sciences and Hu- manities Research Council of Canada (Ottawa, Ontario, Canada), the Quebec Fund for Research on Society and Cul- ture (Quebec City, Quebec, Canada), the Quebec Fund for Research on Na- ture and Technology (Quebec City, Que- bec, Canada), the Health Research Fund of Quebec (Quebec City, Quebec), Quebec’s Ministry of Research, Sci- ence and Technology (Quebec City, Quebec, Canada), Human Resources Development Canada (Ottawa, Ontario, Canada), Health Canada (Ottawa, On- tario, Canada), the National Science Foundation (Arlington, VA), the Univer- sity of Montreal (Montreal, Quebec, Canada), Laval University (Quebec City, TABLE 4 Contrasts Derived From Multinomial Regressions Between Joint Nighttime Sleep Duration and Hyperactivity Trajectories in Early Childhood

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A simple method for estimating relative risk using logistic regression

A simple method for estimating relative risk using logistic regression

However, these statistical methods (binomial and Cox regression) are not widely available in freeware (such as Epidat or Epi-Info). Therefore, the ability to estimate PRs and RRs in multivariate models could be limited in research groups with scant resources. In this article, a strategy for estimating RRs with ordinary logistic regres- sion is proposed. This new method could be useful for identifying risk factors and estimating the impact of health interventions in developing countries.

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The Role of Children's Education for the Mental Health of Aging Migrants in Europe

The Role of Children's Education for the Mental Health of Aging Migrants in Europe

Our modelling strategy included the following steps: first, we examined change in the immigration coefficient of the multilevel logistic regressions after including information on respondents’ characteristics that were found to have an effect on mental health, including (1) demographic factors (immigrant status, age, and sex); (2) physical health (chronic diseases and limitations in activities of daily living); (3) socioeconomic status (educational attainment of respondent and his/her partner as well as household income 4 ); (4) social participation (involvement in charity, education or training, sport or social club, religious organisation, political/community activities); and (5) family social capital/support (number of children, children’s education, and frequency of contact between children and parents). The analysis of change in the immigration coefficient indicates that the given independent variables explain some variation in the effect of immigration. Second, we conduct separate analysis with all the explanatory variables for nonimmigrants and immigrants, including citizenship, age at migration and geographical origin of immigrants as additional controls for the latter group. This analysis highlights whether the education of adult children has an independent effect on parental mental health. Finally, we repeat the analyzes using a derived measure of the difference between the educational attainment of child and parent in order to gain further understanding of this relationship.

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Community health centers and primary care access and quality for chronically-ill patients – a case-comparison study of urban Guangdong Province, China

Community health centers and primary care access and quality for chronically-ill patients – a case-comparison study of urban Guangdong Province, China

We fit multivariate logistic regression models to exam- ine patient and institutional factors associated with qual- ity of care for the chronic disease, controlling for patient demographic and health status characteristics (Table 3). Significant associations between types of primary care delivery and all the quality indicators were observed, with the exception of satisfaction to traveling time and receiving secondary prevention. The results indicated that respondents in Dongguan were more likely to per- form well on the quality indicators that measure accessi- bility, continuity, coordination, and comprehensiveness of services. Specifically, the probability of patients in Dongguan getting medical care in the evenings/week- ends/holidays increased by 6.087 times (p < 0.001) com- pared with patients in Guangzhou, and patients in Shenzhen had 3.314 times greater odds than those in Guangzhou. Patients from Dongguan and Shenzhen were more likely to report satisfaction to access out-of- office hours by phone or text message (OR: 2.711 and 1.821 respectively; 95 % CI: 1.655, 4.441 and 1.230, 2.932

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What determines banks’ customer choice? Evidence from transition countries

What determines banks’ customer choice? Evidence from transition countries

Note: This table shows the results of OLS and IV regressions of the (logistic transformation of) the proportion of lending to foreign subsidiaries (columns 1 and 2) and state-owned firms (columns 3 and 4) in total bank lending on bank characteristics (ownership structure and size), per capita GDP, and an index of banks’ perception of the quality of collateral laws. The sample consists of a cross-section of banks in 20 transition economy countries in 2004. All variables are described in Table 2. The omitted ownership group is formed by private domestic banks. In columns 2 and 4, the instruments for the perception of collateral law are the World Bank Doing Business indicator on “depth of credit information” for 2004 and the EBRD legal indicator on the enforcement of charged assets. In columns 2 and 4, we report a Hansen J-test statistic of over-identifying restrictions along with its p-value (using robust standard errors). Robust t-statistics are in parentheses. Asterisks indicate significance at 0.01 (***), 0.05 (**), and 0.10 (*) levels.

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Evaluation of different techniques for generating landslide susceptibility map

Evaluation of different techniques for generating landslide susceptibility map

Algorithms are chosen in accordance with the achievement of the desired goals and objectives of the research. In summary, methods are a bridge between devices and algorithms. For landslide susceptibility, the use of practical and accurate algorithms is indeed vital. These algorithms are usually named after their inventors (Miles et al., 1999; Gupta et al., 1997). Sometimes, devices and methods are also considered as algorithms (Melchiorre et al.,2008; Saito et al.,2009; Pavel et al.,2008; Borgogno et al.,2009; Frattini et al.,2010; Yeon et al.,2010; Pradhan et al.,2010). In the current study, to best of author knowledge, a method called Moderation is proposed for the first time in the study of landslide susceptibility. The current study also employs methods such as the logistic and spatial regressions, Geographically Weighted Regression (GWR), Geographically Altitudinal Weighted regression (GAWR) and Artificial Neural Network (ANN) methods with some data acquired from devices satellite images and aerial photographs.

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Trends in Abstaining From Substance Use in Adolescents: 1975–2014

Trends in Abstaining From Substance Use in Adolescents: 1975–2014

Table 2 presents descriptive statistics for sociodemographic and behavioral characteristics of the analysis sample by lifetime abstinence status and summarizes findings from a multivariate logistic regression model for lifetime abstinence from all substances. The multivariate aORs reported are mutually adjusted for all of the other predictors included in the model. Male students had significantly higher odds for reporting lifetime abstinence (aOR = 1.25; 95% CI = 1.10–1.42) than female students. Compared with non-Hispanic white students, African American students (aOR = 1.53; 95% CI = 1.27–1.85) and those in the other race category (aOR = 1.23; 95% CI = 1.02–1.47) were significantly more likely to report abstinence; there were no significant differences between white and Hispanic students (aOR = 0.98; 95% CI = 0.80–1.21). The aOR that a student from a single- or no-parent household would be abstinent was 67% less than that for a student from a 2-parent family (aOR = 0.67; 95% CI = 0.59–0.76). After controlling for all other variables, students in the West appeared to be 35% more likely to be abstinent than those in the South (aOR = 1.35; 95% CI = 1.04–1.76). In the fully adjusted model, we did not find a statistically significant relationship between the odds of abstaining from substance use and urbanicity of neighborhood, attendance at a college preparatory FIGURE 1

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Academic Dishonesty, Self Control, and General Criminality: A Prospective and Retrospective Study of Academic Dishonesty in a New Zealand University

Academic Dishonesty, Self Control, and General Criminality: A Prospective and Retrospective Study of Academic Dishonesty in a New Zealand University

7 Chen (2004), finding that a three-item index of behavioral self-control explained an additional 9.7% of the variance in past academic dishonesty once various demographic factors had been controlled for. They found stronger support, however, for differential association theory. Cochran, Aleksa, and Sanders (2008) found that whilst self-control was predictive of academic dishonesty, regardless of the level of self-control the perception of formal sanctions for cheating had a uniform deterrence effect on unethical behavior. The only example of a prospective analysis of self-control theory and academic dishonesty we could find was Smith (2004), who allowed university students the opportunity to misreport their mark on a self-marked test in a natural setting after earlier completing the Grasmick, Tittle, Bursik, and Arneklev (1993) self- control scale. Smith used a binary logistic regression with the Grasmick et al. scale as a predictor of cheating, finding that self-control was a statistically significant predictor of cheating – but that model fit was modest, with a Nagelkerke pseudo R-square of 0.18.

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Health related quality of life trajectories and predictors following coronary artery bypass surgery

Health related quality of life trajectories and predictors following coronary artery bypass surgery

The present study also improved upon previous studies by assessing the impact of operational and post-surgical var- iables. It has been argued that HRQoL in the months after CABGS may be affected by environmental factors such as processes and structures of care, complications of the sur- gery, or interim life change or health events [1,14]. The present study demonstrated that PCS group membership was adversely affected by surgical variables such as experi- encing a new cardiac arrhythmia and the recording of higher pulmonary blood pressure during surgery. MCS group membership was not significantly associated with any of these variables in the final logistic regression. Attendance at CR was significantly associated with MCS improver group when medical variables were analysed sep- arately, but was not significant in the presence of compet- ing variables. This finding is consistent with other studies that have found little or no difference between CR attend- ers and non-attenders in HRQoL measured by the SF-36 [7,32]. It has been suggested that CR is not sufficiently intensive to influence recovery of HRQoL [7]. CR was only found to benefit physical function in a recent randomised controlled trial of an 18-session program which compared CR with usual care [61].

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