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1. The Canopy-Forming Alga Ericaria brachycarpa (J.Agardh) Molinari-Novoa & Guiry (Fucales, Phaeophyceae) Shows Seasonal and Depth Adaptation to the Incoming Light Levels

Author:
Sant, Natàlia; Ballesteros, Enric
Source:
Cryptogamie 2021 v.42 no.6 pp. 67-75
ISSN:
1776-0984
Subject:
variance,   etc   ; Fucales; algae; photosynthesis;     Show all 4 Subjects
Abstract:
... The shallow water canopy-forming alga Ericaria brachycarpa (J.Agardh) Molinari-Novoa & Guiry shows higher photosynthetic efficiency (α), maximum photosynthetic rates (Pₘₐₓ), light at compensation (Ic) and dark respiration (Rd) in individuals collected at the lower depth limit of distribution of the species (20 m) than at shallower depths (2 and 10 m). Photosynthesis at saturation light levels (Pₛₐ ...
DOI:
10.5252/cryptogamie-algologie2021v42a6

2. A comparison of isometric and amalgamation logratio balances in compositional data analysis

Author:
Greenacre, Michael; Grunsky, Eric; Bacon-Shone, John
Source:
Computers & geosciences 2021 v.148 pp. 104621
ISSN:
0098-3004
Subject:
variance,   etc   ; data collection; geometry;     Show all 3 Subjects
Abstract:
... The isometric logratio transformation, in the form of what has been called a “balance”, has been promoted as a way to contrast two groups of parts in a compositional data set by forming ratios of their respective geometric means. This transformation has attractive theoretical properties and hence provides a useful reference, but geometric means are highly affected by parts with small relative valu ...
DOI:
10.1016/j.cageo.2020.104621

3. Improved Doubly Robust Estimation in Learning Optimal Individualized Treatment Rules

Author:
Pan, Yinghao; Zhao, Ying-Qi
Source:
Journal of the American Statistical Association 2021 v.116 no.533 pp. 283-294
ISSN:
1537-274X
Subject:
variance,   etc   ; models; patients;     Show all 3 Subjects
Abstract:
... Individualized treatment rules (ITRs) recommend treatment according to patient characteristics. There is a growing interest in developing novel and efficient statistical methods in constructing ITRs. We propose an improved doubly robust estimator of the optimal ITRs. The proposed estimator is based on a direct optimization of an augmented inverse-probability weighted estimator of the expected clin ...
DOI:
10.1080/01621459.2020.1725522

4. Contribution of social genetic effects in variance components estimation for body weight in Nigerian indigenous chickens raised in a tropical humid location

Author:
Adenaike, A. S.; Peters, S. O.; Ogundero, A. E.; Wonodi, J. O.; Ikeobi, C. O. N.
Source:
Tropical animal health and production 2021 v.53 no.1 pp. 124
ISSN:
0049-4747
Subject:
genetic variance; variance,   etc   ; ; animal health; body weight; covariance; farms;     Show all 7 Subjects
Abstract:
... Social interactions among chickens can have a great unfavourable effect on economic returns in a poultry farm. The purpose of this study was to use four models to examine the influence of social genetic influences on the variation in body weight of Nigerian indigenous chickens. Sex was treated as the fixed effect within the models. Direct additive genetic, social genetic, and family effects and co ...
DOI:
10.1007/s11250-021-02568-8

5. Learning from differences: Abiotic determinism of benthic communities in Northern Taiwan

Author:
Hsiao, Wanchien Victoria; Lin, Yuting Vicky; Lin, Huei-Ting; Denis, Vianney
Source:
Marine environmental research 2021 v.170 pp. 105361
ISSN:
0141-1136
Subject:
variance,   etc   ; regression analysis; research; Taiwan;     Show all 4 Subjects
Abstract:
... Differences in the initial configuration of ecological communities may lead to contrasting trajectories when facing environmental changes. Here, we propose to uncover the determinism of benthic communities by carrying out a detailed investigation of their response to small-scale modification of environmental conditions, including physical, chemical, and geological factors. At ten locations (confou ...
DOI:
10.1016/j.marenvres.2021.105361

6. Modeling time-varying selectivity in size-structured assessment models

Author:
Cronin-Fine, Lee; Punt, André E.
Source:
Fisheries research 2021 v.239 pp. 105927
ISSN:
0165-7836
Subject:
variance,   etc   ; fish; mortality; probability; research;     Show all 5 Subjects
Abstract:
... Within fisheries assessments, selectivity refers to the relative probability of a fish of a particular size or age being caught. Selectivity, typically modelled using a parametric function, is informed primarily by age- and size-composition data. This function can vary annually, and not accounting for this variation can result in biased estimates of abundance and mortality. Past simulation studies ...
DOI:
10.1016/j.fishres.2021.105927

7. Stationary hydrological frequency analysis coupled with uncertainty assessment under nonstationary scenarios

Author:
Vidrio-Sahagún, Cuauhtémoc Tonatiuh; He, Jianxun; Kasiviswanathan, K.S.; Sen, Subhamoy
Source:
Journal of hydrology 2021 v.598 pp. 125725
ISSN:
0022-1694
Subject:
variance,   etc   ; Bayesian theory; hydrometeorology; uncertainty;     Show all 4 Subjects
Abstract:
... The use of the nonstationary hydrological frequency analysis (HFA) has been prompted when nonstationarity is diagnosed in hydrometeorological data. However, the inconclusive identification of the physical process(es) and driver(s) behind the nonstationarity challenges the identification of an appropriate model structure, and consequently might hinder its reliable implementation. To date, no solid ...
DOI:
10.1016/j.jhydrol.2020.125725

8. Development of land-use regression models to estimate particle mass and number concentrations in Taichung, Taiwan

Author:
Chang, Ta-Yuan; Tsai, Ching-Chih; Wu, Chang-Fu; Chang, Li-Te; Chuang, Kai-Jen; Chuang, Hsiao-Chi; Young, Li-Hao
Source:
Atmospheric environment 2021 v.252 pp. 118303
ISSN:
1352-2310
Subject:
variance,   etc   ; environment; land use; Taiwan;     Show all 4 Subjects
Abstract:
... Land-use regression (LUR) models have been used to estimate particle mass concentration (PMC), but few studies apply it to predict particle number concentration (PNC) at different sizes. This study aimed to determine both PMC and PNC throughout one year to establish predictive models in Taichung, Taiwan. The annual averages of PM₁₀, PM₂.₅, and PM₁ were 71 ± 46 μg/m³, 44 ± 35 μg/m³, and 32 ± 28 μg/ ...
DOI:
10.1016/j.atmosenv.2021.118303

9. Statistical Inference for Online Decision Making via Stochastic Gradient Descent

Author:
Chen, Haoyu; Lu, Wenbin; Song, Rui
Source:
Journal of the American Statistical Association 2021 v.116 no.534 pp. 708-719
ISSN:
1537-274X
Subject:
variance,   etc   ; algorithms; probability; statistical inference;     Show all 4 Subjects
Abstract:
... Online decision making aims to learn the optimal decision rule by making personalized decisions and updating the decision rule recursively. It has become easier than before with the help of big data, but new challenges also come along. Since the decision rule should be updated once per step, an offline update which uses all the historical data is inefficient in computation and storage. To this end ...
DOI:
10.1080/01621459.2020.1826325

10. Nonsuicidal self-injury and suicide attempts are uniquely associated with eating disorder pathology and behaviors over and above negative urgency

Author:
Izquierdo, Alyssa M.; Fischer, Sarah
Source:
Eating behaviors 2021 v.41 pp. 101483
ISSN:
1471-0153
Subject:
variance,   etc   ; history; inventories; males; suicide;     Show all 5 Subjects
Abstract:
... Nonsuicidal self-injury (NSSI) and suicidal behaviors are prevalent in individuals with eating disorders (EDs). Negative urgency (NU; the tendency to act rashly when distressed) is a common correlate of NSSI, suicide, and ED pathology. The aim of this study was to examine whether lifetime history of NSSI and suicide attempts (SA) contributed unique variance to current ED pathology after controllin ...
DOI:
10.1016/j.eatbeh.2021.101483

11. A New Cycle-Slip Repair Method for Dual-Frequency BDS Against the Disturbances of Severe Ionospheric Variations and Pseudoranges with Large Errors

Author:
Li, Dehai; Dang, Yaming; Yuan, Yunbin; Mi, Jinzhong
Source:
Remote Sensing 2021 v.13 no.5
ISSN:
2072-4292
Subject:
variance,   etc   ; models; risk; satellites; storms;     Show all 5 Subjects
Abstract:
... Many Beidou navigation satellite system (BDS) receivers or boards provide dual-frequency measurements to conduct precise positioning and navigation for low-power consumption. Cycle-slip processing is a primary work to guarantee consistent, precise positioning with the phase data. However, the cycle-slip processing of BDS dual-frequency phases still follows with those of existing GPS methods. For s ...
DOI:
10.3390/rs13051037

12. Consequences of error in natural mortality and its estimation in stock assessment models

Author:
Punt, André E.; Castillo-Jordán, Claudio; Hamel, Owen S.; Cope, Jason M.; Maunder, Mark N.; Ianelli, James N.
Source:
Fisheries research 2021 v.233 pp. 105759
ISSN:
0165-7836
Subject:
variance,   etc   ; biomass; fish; mortality; research;     Show all 5 Subjects
Abstract:
... Natural mortality (M) is often considered to be one of the most important parameters in a fish stock assessment and affects productivity estimates for the population. However, it is also among the most difficult parameters to estimate using commonly available data. The magnitude of error (both bias and variance) when estimating this parameter can be substantial and can be affected by ignoring its ...
DOI:
10.1016/j.fishres.2020.105759

13. Predicting rock failure with the critical slowing down theory

Author:
Zhang, Zhenghu; Li, Yingchun; Hu, Lihua; Tang, Chun’an; Zheng, Hongchun
Source:
Engineering geology 2021 v.280 pp. 105960
ISSN:
0013-7952
Subject:
variance,   etc   ; acoustics; autocorrelation; brittleness; deformation;     Show all 5 Subjects
Abstract:
... Early warning signals of critical transitions in rock before its sudden failure are key for forecasting geological disasters in rock engineering. Here we examined the critical slowing down characteristics of acoustic emission (AE) and precursory signals preceding catastrophic rock failure. We conducted laboratory experiments on different types of rock specimens subjected to tension and compression ...
DOI:
10.1016/j.enggeo.2020.105960

14. Bootstrapping non-stationary stochastic volatility

Author:
Boswijk, H. Peter; Cavaliere, Giuseppe; Georgiev, Iliyan; Rahbek, Anders
Source:
Journal of econometrics 2021 v.224 no.1 pp. 161-180
ISSN:
0304-4076
Subject:
variance,   etc   ; probability; stochastic processes; time series analysis;     Show all 4 Subjects
Abstract:
... In this paper we investigate to what extent the bootstrap can be applied to conditional mean models, such as regression or time series models, when the volatility of the innovations is random and possibly non-stationary. In fact, the volatility of many economic and financial time series displays persistent changes and possible non-stationarity. However, the theory of the bootstrap for such models ...
DOI:
10.1016/j.jeconom.2021.01.005

15. Interface homogenization and its relationship with tensile properties of laser-arc hybrid welded Al/steel butt-joint via beam oscillation

Author:
Gao, Ming; Zhang, Yazhou; Meng, Yunfei
Source:
Journal of materials science 2021 v.56 no.25 pp. 14126-14138
ISSN:
0022-2461
Subject:
variance,   etc   ; homogenization; quantitative analysis; steel; tensile strength;     Show all 5 Subjects
Abstract:
... Homogenized intermetallic compound (IMC) layer at interface was achieved in laser-arc hybrid butt welded Al/steel dissimilar metals through beam oscillation. The beam oscillation reduced the macrosegregation of Fe element in the weld, which increased the uniformity of IMC layer by 443 times as its thickness variance (δ) decreased from 0.9767 to 0.0022. It was found that the tensile properties of w ...
DOI:
10.1007/s10853-021-06234-0

16. Genetic associations between growth traits and age at first calving in guzera cattle using random regression models

Author:
da Gama, Manuela Pires Monteiro; de Paz, Claudia Cristina Paro; Junior, Mário Luiz Santana; Ventura, Henrique Torres; Bernardes, Priscila Arrigucci; Faro, Lenira El
Source:
Livestock science 2021 pp. 104585
ISSN:
1871-1413
Subject:
variance,   etc   ; animal models; body weight; cows; heritability;     Show all 5 Subjects
Abstract:
... The aim of this study was to estimate genetic associations between body weight (BW), scrotal circumference (SC), and age at first calving (AFC) in Guzera cattle using random regression models. The analyses used 159,366 and 23,780 records of BW and SC obtained between 335 and 724 days of age and divided into classes at intervals of 10 days, as well as 63,596 records of AFC. A multitrait animal mode ...
DOI:
10.1016/j.livsci.2021.104585

17. How temperature variation affects white-rot fungi mycelial growth dynamics: A nonlinear mixed models approach

Author:
Negrão, Djanira Rodrigues; Mischan, Martha Maria; de Pinho, Sheila Zambello; de Carvalho, Lídia Raquel; Gomes, Rafaela Lanças; de Souza Passos, José Raimundo
Source:
Fungal biology 2021
ISSN:
1878-6146
Subject:
variance,   etc   ; Weibull statistics; covariance; mycology; temperature;     Show all 5 Subjects
Abstract:
... This study aimed to model mycelial growth in a factorial experiment with two species of white rot fungi growing at five temperatures. The nonlinear models evaluated were logistic, Gompertz, Weibull and von Bertalanffy. The adjustments were performed first by evaluating the fixed and mixed-effects models with random effects, added to the fixed parameters. Then, the best adjusted model was improved ...
DOI:
10.1016/j.funbio.2021.05.007

18. The Impacts of Spatial Resolution, Viewing Angle, and Spectral Vegetation Indices on the Quantification of Woody Mediterranean Species Seasonality Using Remote Sensing

Author:
Elbaz, Shelly; Sheffer, Efrat; Lensky, Itamar M.; Levin, Noam
Source:
Remote Sensing 2021 v.13 no.10
ISSN:
2072-4292
Subject:
variance,   etc   ; cameras; satellites; shrublands; woody plants; Israel;     Show all 6 Subjects
Abstract:
... Discriminating between woody plant species using a single image is not straightforward due to similarity in their spectral signatures, and limitations in the spatial resolution of many sensors. Seasonal changes in vegetation indices can potentially improve vegetation mapping; however, for mapping at the individual species level, very high spatial resolution is needed. In this study we examined the ...
DOI:
10.3390/rs13101958

19. Study on Radar Echo-Filling in an Occlusion Area by a Deep Learning Algorithm

Author:
Yin, Xiaoyan; Hu, Zhiqun; Zheng, Jiafeng; Li, Boyong; Zuo, Yuanyuan
Source:
Remote Sensing 2021 v.13 no.9
ISSN:
2072-4292
Subject:
variance,   etc   ; algorithms; data quality; models; radar; weather;     Show all 6 Subjects
Abstract:
... Radar beam blockage is an important error source that affects the quality of weather radar data. An echo-filling network (EFnet) is proposed based on a deep learning algorithm to correct the echo intensity under the occlusion area in the Nanjing S-band new-generation weather radar (CINRAD/SA). The training dataset is constructed by the labels, which are the echo intensity at the 0.5° elevation in ...
DOI:
10.3390/rs13091779

20. Performance and Evaluation of GNSS Receiver Vector Tracking Loop Based on Adaptive Cascade Filter

Author:
Yang, Haotian; Zhou, Bin; Wang, Lixin; Wei, Qi; Ji, Feng; Zhang, Rong
Source:
Remote Sensing 2021 v.13 no.8
ISSN:
2072-4292
Subject:
variance covariance matrix,   etc   ; computer software; satellites;     Show all 3 Subjects
Abstract:
... In the scenario of high dynamics and low C/N₀, the discriminator output of a GNSS tracking loop is noisy and nonlinear. The traditional method uses a fixed-gain loop filter for error estimation, which is prone to lose lock and causes inaccurate navigation and positioning. This paper proposes a cascaded adaptive vector tracking method based on the KF+EKF architecture through the GNSS Software defin ...
DOI:
10.3390/rs13081477