Factors affecting commercial trawl fleet landings in a multispecies fishery

Retained catches of trawl fleet in Chalkis fishing port-market, Greece, were analysed using generalized linear models (GLMs) in an attempt to identify factors that influence the total landings of the groundfish fisheries. Main effects in the model included a factor for vessel tonnage that determined fishing power, as well as factors for month and fishing area. Covariates examined were all found to have a significant effect on the retained catches, with month and vessel capacity alone explaining 38% and 30% respectively of the total variation of the data. Significant interactions observed indicate that the fluctuations in retained catch differed by fishing area and month as well as by fishing area and vessel category. Within vessel categories, month and fishing area also had significant effects on the retained catches, with fishing area being more important than month for the smallest vessels. Results indicate that the modelling approach of retained catches from trawl fisheries is a promising method for obtaining representative abundance indices.

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Breeding value evaluation in Polish fur animals: Factors affecting pelt prices in the international trading system

Czech Journal of Animal Science ◽

10.17221/4167-cjas ◽

2011 ◽

Vol 50 (No. 6) ◽

pp. 266-272 ◽

Cited By ~ 5

Author(s):

H. Wierzbicki

Keyword(s):

Total Variation ◽

Linear Models ◽

Character Traits ◽

Breeding Value ◽

Auction House ◽

Factors Affecting ◽

Value Evaluation ◽

International Trading ◽

Percent Contribution ◽

Main Effects

The aim of this study was to determine the contribution of pelt character traits to the price the skins could reach at an auction house. The paper also presents an analysis of trends showing the changes in the contribution of pelt character traits to the pelt price over 4 seasons. 10 177 records of arctic fox pelts sold at the Helsinki Auction House in the seasons 2000–2004 were analysed. The pelts were graded and sorted according to their character traits: size, quality, colour clarity and colour darkness. The significance of the pelt character traits and their effects on the pelt price were tested using the GLM procedure and two linear models (Model 1 – without interactions between main effects, Model 2 – with interactions between main effects). The total variation of the pelt price was partitioned into components connected with random effects included in the models using the REML and VARCOMP procedure. Then, based on the estimated variance components, the percent contribution of each component to the total variation of the pelt price was calculated. It was found that, depending on the model and season, the pelt price was mostly influenced by skin size and quality, whereas colour type and colour clarity had small effects on the pelt price. However, the effect of the skin size on the pelt price in the analysed seasons decreased, whereas the effects of the remaining three traits on the pelt price slightly increased.  

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Probability matrix decomposition models and main-effects generalized linear models for the analysis of replicated binary associations

Computational Statistics & Data Analysis ◽

10.1016/s0167-9473(01)00029-9 ◽

2001 ◽

Vol 38 (2) ◽

pp. 217-233 ◽

Cited By ~ 5

Author(s):

Michel Meulders ◽

Paul De Boeck ◽

Iven Van Mechelen

Keyword(s):

Generalized Linear Models ◽

Linear Models ◽

Matrix Decomposition ◽

Decomposition Models ◽

Binary Associations ◽

Main Effects

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Analysis of factors affecting superovulatory responses in ruminants

The Journal of Agricultural Science ◽

10.1017/s0021859600071252 ◽

1995 ◽

Vol 124 (1) ◽

pp. 61-70 ◽

Cited By ~ 7

Author(s):

J. A. Woolliams ◽

Z. W. Luo ◽

B. Villanueva ◽

D. Waddington ◽

P. J. Broadbent ◽

...

Keyword(s):

Generalized Linear Models ◽

Linear Models ◽

Negative Binomial ◽

Commercial Application ◽

Data Set ◽

Factors Affecting ◽

Binomial Distributions ◽

Breeding Schemes ◽

Over Dispersion ◽

Mean Variance

SUMMARYData on ovulation rate and numbers of ova and transferable embryos recovered from superovulated cattle and sheep were analysed using generalized linear models, quasi-likelihood, restricted maximum likelihood (REML) and generalized linear mixed models (GLMMS). The data pertained to the operation of nucleus breeding schemes in cattle and the commercial application of embryo transfer in sheep.Results of the analyses showed that generalized linear models involving Poisson and Binomial distributions were inappropriate because of over-dispersion, and that analyses using quasi-likelihood to model negative binomial and β-binomial distributions were more suitable. Factors identified as important in determining the results in cattle were the number of previous superovulations (a higher proportion of transferable embryos were obtained in the initial flush compared to subsequent recoveries in two out of three sets of data), the donor (significant in all analyses with repeated recoveries) and its mate (significant in some analyses). In sheep, the use of pFSH or hMG for superovulation increased embryo yields above those obtained with PMSG + GnRH. Analyses of a further data set for sheep showed the effect of breed was ambiguous.The effects of donors and their mates were treated as random effects in analyses involving REML and GLMMS. Results showed that the repeatability of the number of transferable embryos produced per donor ranged between 0·13 and 0·23 in three sets of data and was significant in all cases. In these analyses the variance among mates was not significantly different from zero.The results of analyses were used to develop a random generator to simulate the numbers of ova and embryos recovered from a cow following superovulation. By sampling from negative binomial distributions where the scale factor used for each cow was a normally distributed deviate, distributions were obtained which had the same mean, variance and repeatability as those observed.

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Analysing multiple variables per subject

Oxford Handbook of Medical Statistics ◽

10.1093/med/9780199551286.003.0012 ◽

2010 ◽

pp. 393-445

Author(s):

Janet L. Peacock ◽

Philip J. Peacock

Keyword(s):

Missing Data ◽

Model Selection ◽

Multiple Regression ◽

Analysis Of Variance ◽

Generalized Linear Models ◽

Linear Models ◽

Non Linear ◽

Multiple Variables ◽

Main Effects

Multiple variables per subject 394 Multifactorial methods: overview 396 Multifactorial methods: model selection 398 Multifactorial methods: challenges 400 Missing data 402 Generalized linear models 404 Multiple regression 406 Multiple regression: examples 408 Multiple regression and analysis of variance 412 Main effects and interactions 414 Linear and non-linear terms ...

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A LPUE (LANDING PER UNIT EFFORT) ANALYSIS OF THE TRAWL FISHERY FOR THE COASTAL SHRIMPS Artemesia longinaris AND Pleoticus muelleri OFF SOUTHERN BRAZIL

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592014061306204 ◽

2014 ◽

Vol 62 (4) ◽

pp. 235-245 ◽

Cited By ~ 1

Author(s):

Cassiana Baptista Metri ◽

José Angel Alvarez Perez

Keyword(s):

Generalized Linear Models ◽

Linear Models ◽

Rio Grande ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Annual Cycles ◽

Factors Affecting ◽

Trawl Fishery ◽

One Year ◽

Stock Abundance

The Argentine stiletto shrimp (Artemesia longinaris) and the Argentine red shrimp (Pleoticus muelleri) currently sustain an important fishery in terms of tonnage and revenues in southern Brazil. This study analyzed the factors affecting the abundance of both species through the application of Generalized Linear Models to landing-per-unit-of-effort (LPUE) data of the trawl fleet operating on the main fishing grounds between 1998 and 2005. The main patterns of LPUE variability of both species were attributed do the effect of seasons and annual cycles. Larger yields were obtained in the southern shallow areas of Rio Grande do Sul State. No tendency either to an increase or a decline in stock abundance was observed, but the effort in one year was affected by the success of the captures of the previous year. In the last two years analyzed the abundance and the total captures declined.

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From Generalized Linear Models to Neural Networks, and Back

SSRN Electronic Journal ◽

10.2139/ssrn.3491790 ◽

2019 ◽

Cited By ~ 5

Author(s):

Mario V. Wuthrich

Keyword(s):

Neural Networks ◽

Generalized Linear Models ◽

Linear Models

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Effect of Different Dentifrices, Bleaching with 35% Hydrogen Peroxide, and Red Wine on Surface Color and Roughness of Bovine Enamel

Current Dentistry ◽

10.2174/2542579x02999200817112951 ◽

2020 ◽

Vol 02 ◽

Author(s):

RM Garcia ◽

WF Vieira-Junior ◽

JD Theobaldo ◽

NIP Pini ◽

GM Ambrosano ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Generalized Linear Models ◽

Repeated Measures ◽

Red Wine ◽

Linear Models ◽

Artificial Saliva ◽

Surface Color ◽

Dental Bleaching ◽

Surface Alteration ◽

Bovine Enamel

Objective: To evaluate color and roughness of bovine enamel exposed to dentifrices, dental bleaching with 35% hydrogen peroxide (HP), and erosion/staining by red wine. Methods: Bovine enamel blocks were exposed to: artificial saliva (control), Oral-B Pro-Health (stannous fluoride with sodium fluoride, SF), Sensodyne Repair & Protect (bioactive glass, BG), Colgate Pro-Relief (arginine and calcium carbonate, AR), or Chitodent (chitosan, CHI). After toothpaste exposure, half (n=12) of the samples were bleached (35% HP), and the other half were not (n=12). The color (CIE L*a* b*, ΔE), surface roughness (Ra), and scanning electron microscopy were evaluated. Color and roughness were assessed at baseline, post-dentifrice and/or -dental bleaching, and after red wine. The data were subjected to analysis of variance (ANOVA) (ΔE) for repeated measures (Ra), followed by Tukey ́s test. The L*, a*, and b* values were analyzed by generalized linear models (a=0.05). Results: The HP promoted an increase in Ra values; however, the SF, BG, and AR did not enable this alteration. After red wine, all groups apart from SF (unbleached) showed increases in Ra values; SF and AR promoted decreases in L* values; AR demonstrated higher ΔE values, differing from the control; and CHI decreased the L* variation in the unbleached group. Conclusion: Dentifrices did not interfere with bleaching efficacy of 35% HP. However, dentifrices acted as a preventive agent against surface alteration from dental bleaching (BG, SF, and AR) or red wine (SF). Dentifrices can decrease (CHI) or increase (AR and SF) staining by red wine.

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Economic burden of readmission due to postoperative cerebrospinal fluid leak in Chinese patients

Journal of Comparative Effectiveness Research ◽

10.2217/cer-2020-0067 ◽

2020 ◽

Vol 9 (16) ◽

pp. 1105-1115

Author(s):

Shuqing Wu ◽

Xin Cui ◽

Shaoyu Zhang ◽

Wenqi Tian ◽

Jiazhen Liu ◽

...

Keyword(s):

Cerebrospinal Fluid ◽

Generalized Linear Models ◽

Economic Burden ◽

Linear Models ◽

Chinese Patients ◽

Cerebrospinal Fluid Leakage ◽

Index Hospitalization ◽

Real World Data ◽

Factors Associated ◽

Hospitalization Cost

Aim: This real-world data study investigated the economic burden and associated factors of readmissions for cerebrospinal fluid leakage (CSFL) post-cranial, transsphenoidal, or spinal index surgeries. Methods: Costs of CSFL readmissions and index hospitalizations during 2014–2018 were collected. Readmission cost was measured as absolute cost and as percentage of index hospitalization cost. Factors associated with readmission cost were explored using generalized linear models. Results: Readmission cost averaged US$2407–6106, 35–94% of index hospitalization cost. Pharmacy costs were the leading contributor. Generalized linear models showed transsphenoidal index surgery and surgical treatment for CSFL were associated with higher readmission costs. Conclusion: CSFL readmissions are a significant economic burden in China. Factors associated with higher readmission cost should be monitored.

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