scholarly journals Correlated binomial models and correlation structures

2006 ◽  
Vol 39 (50) ◽  
pp. 15365-15378 ◽  
Author(s):  
Masato Hisakado ◽  
Kenji Kitsukawa ◽  
Shintaro Mori
Keyword(s):  
Correlation Structures ◽  
Correlated Binomial ◽  
Binomial Models

Mapping the Topics and Evolutions of Chinese Children’s Bestsellers

Libri ◽  
2020 ◽  
Vol 70 (4) ◽  
pp. 305-317
Author(s):  
Jiming Hu ◽  
Xiang Zheng ◽  
Peng Wen ◽  
Jie Xu
Keyword(s):  
Social Network ◽  
Quantitative Analysis ◽  
Network Analysis ◽  
Intellectual Structure ◽  
Structure Evolution ◽  
Children's Books ◽  
Children’S Books ◽  
Correlation Structures ◽  
The World ◽  
Data Source

AbstractChildren’s books involve a large number of topics. Research on them has been paid much attention to by both scholars and practitioners. However, the existing achievements do not focus on China, which is the fastest growing market for children’s books in the world. Studies using quantitative analysis are low in number, especially on the intellectual structure, evolution patterns, and development trends of topics of children’s bestsellers in China. Dangdang.com, the biggest Chinese online bookstore, was chosen as a data source to obtain children’s bestsellers, and topic words in them were extracted from brief introductions. With the aid of co-occurrence theory and tools of social network analysis and visualization, the distribution, correlation structures, and evolution patterns of topics were revealed and visualized. This study shows that topics of Chinese children’s bestsellers are broad and relatively concentrated, but their distribution is unbalanced. There are four distinguished topic communities (Living, Animal, World, and Child) in terms of centrality and maturity, and they all establish their individual systems and tend to be mature. The evolution of these communities tends to be stable with powerful continuity.

scholarly journals Intra-cluster correlations from the CLustered OUtcome Dataset bank to inform the design of longitudinal cluster trials

2021 ◽  
pp. 174077452110208
Author(s):  
Elizabeth Korevaar ◽  
Jessica Kasza ◽  
Monica Taljaard ◽  
Karla Hemming ◽  
Terry Haines ◽  
...  
Keyword(s):  
Sample Size ◽  
Discrete Time ◽  
Correlation Coefficients ◽  
Time Decay ◽  
Randomised Trials ◽  
Cluster Randomised Trials ◽  
Cluster Randomised ◽  
Sample Size Calculations ◽  
Correlation Structures ◽  
Cluster Correlation

Background: Sample size calculations for longitudinal cluster randomised trials, such as crossover and stepped-wedge trials, require estimates of the assumed correlation structure. This includes both within-period intra-cluster correlations, which importantly differ from conventional intra-cluster correlations by their dependence on period, and also cluster autocorrelation coefficients to model correlation decay. There are limited resources to inform these estimates. In this article, we provide a repository of correlation estimates from a bank of real-world clustered datasets. These are provided under several assumed correlation structures, namely exchangeable, block-exchangeable and discrete-time decay correlation structures. Methods: Longitudinal studies with clustered outcomes were collected to form the CLustered OUtcome Dataset bank. Forty-four available continuous outcomes from 29 datasets were obtained and analysed using each correlation structure. Patterns of within-period intra-cluster correlation coefficient and cluster autocorrelation coefficients were explored by study characteristics. Results: The median within-period intra-cluster correlation coefficient for the discrete-time decay model was 0.05 (interquartile range: 0.02–0.09) with a median cluster autocorrelation of 0.73 (interquartile range: 0.19–0.91). The within-period intra-cluster correlation coefficients were similar for the exchangeable, block-exchangeable and discrete-time decay correlation structures. Within-period intra-cluster correlation coefficients and cluster autocorrelations were found to vary with the number of participants per cluster-period, the period-length, type of cluster (primary care, secondary care, community or school) and country income status (high-income country or low- and middle-income country). The within-period intra-cluster correlation coefficients tended to decrease with increasing period-length and slightly decrease with increasing cluster-period sizes, while the cluster autocorrelations tended to move closer to 1 with increasing cluster-period size. Using the CLustered OUtcome Dataset bank, an RShiny app has been developed for determining plausible values of correlation coefficients for use in sample size calculations. Discussion: This study provides a repository of intra-cluster correlations and cluster autocorrelations for longitudinal cluster trials. This can help inform sample size calculations for future longitudinal cluster randomised trials.

scholarly journals Factors Contributing to the Relationship between Driving Mileage and Crash Frequency of Older Drivers

2019 ◽  
Vol 11 (23) ◽  
pp. 6643 ◽  
Author(s):  
Lee ◽  
Guldmann ◽  
Choi
Keyword(s):  
Negative Binomial ◽  
Age Groups ◽  
Urban Environments ◽  
Vehicle Miles Traveled ◽  
Crash Frequency ◽  
Rural Environments ◽  
Lower Likelihood ◽  
Conditional Autoregressive ◽  
The Relationship ◽  
Binomial Models

As a characteristic of senior drivers aged 65 +, the low-mileage bias has been reported in previous studies. While it is thought to be a well-known phenomenon caused by aging, the characteristics of urban environments create more opportunities for crashes. This calls for investigating the low-mileage bias and scrutinizing whether it has the same impact on other age groups, such as young and middle-aged drivers. We use a crash database from the Ohio Department of Public Safety from 2006 to 2011 and adopt a macro approach using Negative Binomial models and Conditional Autoregressive (CAR) models to deal with a spatial autocorrelation issue. Aside from the low-mileage bias issue, we examine the association between the number of crashes and the built environment and socio-economic and demographic factors. We confirm that the number of crashes is associated with vehicle miles traveled, which suggests that more accumulated driving miles result in a lower likelihood of being involved in a crash. This implies that drivers in the low mileage group are involved in crashes more often, regardless of the driver’s age. The results also confirm that more complex urban environments have a higher number of crashes than rural environments.

p Value Adjustments for Multiple Tests in Multivariate Binomial Models

1989 ◽  
Vol 84 (407) ◽  
pp. 780 ◽  
Author(s):  
Peter H. Westfall ◽  
S. Stanley Young
Keyword(s):  
P Value ◽  
Multiple Tests ◽  
Binomial Models

Zapatista and counter-Zapatista protests

2012 ◽  
Vol 49 (3) ◽  
pp. 459-472 ◽  
Author(s):  
María Inclán
Keyword(s):  
Negative Binomial ◽  
Empirical Test ◽  
Party Competition ◽  
Public Works ◽  
Social Programs ◽  
Reciprocal Effect ◽  
Systematic Analysis ◽  
Binomial Models ◽  
Different Levels ◽  
Protest Activity

This study represents the first systematic analysis of the interactions between pro-Zapatista and counter-Zapatista protestors in Chiapas, Mexico, and the first empirical test of movement–countermovement theories in a transitional democracy. Three claims are tested: (1) movement protests trigger countermovement protest activity; (2) different political parties at different levels of government trigger movement–countermovement protest activity; and (3) victories won by one side of a conflict, viewed as procedural concessions, trigger further pro- and countermovement protest activity. These hypotheses are tested using negative binomial models and data on Zapatista-related protest activity between 1994 and 2003. The results show that: (1) movement and countermovement protests have a positive, reciprocal effect on both groups' future protest activity; (2) movement and countermovement protesting groups use the dominant political party as a target of protest. The characteristics of the electoral cycle and rise of multi-party competition at all levels of government do not have a consistent effect on protest activity; (3) granting procedural concessions to pro-movement actors generates more protest activity among both groups. However, granting procedural concessions via social programs and public works to the population irrespective of its sympathy to either side of the movement–countermovement conflict decreases movement protests and increases countermovement protests.

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