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1. Object-based land surface segmentation scale optimisation: An ill-structured problem

Author:
Louw, Gerrit; van Niekerk, Adriaan
Source:
Geomorphology 2019 v.327 pp. 377-384
ISSN:
0169-555X
Subject:
variance,   etc   ; morphometry; probability;     Show all 3 Subjects
Abstract:
... The segmentation of continuous land surfaces into morphologically representative objects has received increasing attention in recent years. Multi-resolution segmentation (MRS) has been shown to delimit morphological boundaries accurately and the use of unsupervised data-driven local variance (LV) based methods for detecting characteristic levels of scale parameter (SP) in land surfaces has been es ...
DOI:
10.1016/j.geomorph.2018.11.021

2. Pattern Detection and Scaling Laws of Daily Water Demand by SOM: an Application to the WDN of Naples, Italy

Author:
Padulano, Roberta; Del Giudice, Giuseppe
Source:
Water resources management 2019 v.33 no.2 pp. 739-755
ISSN:
0920-4741
Subject:
variance,   etc   ; equations; Italy;     Show all 3 Subjects
Abstract:
... In the present paper, a novel method is provided to detect significant daily consumption patterns and to obtain scaling laws to predict consumption patterns for groups of homogeneous users. The first issue relies on the use of Self-Organizing Map to gain insights about the initial assumption of distinct homogeneous consumption groups and to find additional clusters based on calendar dates. Non-dim ...
DOI:
10.1007/s11269-018-2140-0

3. Comparing a standardized to a product-specific emoji list for evaluating food products by children

Author:
Schouteten, Joachim J.; Verwaeren, Jan; Gellynck, Xavier; Almli, Valérie L.
Source:
Food quality and preference 2019 v.72 pp. 86-97
ISSN:
0950-3293
Subject:
variance,   etc   ; biscuits; children; correspondence analysis;     Show all 4 Subjects
Abstract:
... There is a growing interest in the emotional associations of children to food products in order to better understand their preferences. Recently, emoji were suggested as a novel way to assess these emotional associations. In this study, 172 children aged 8–11 years evaluated the emotional profile of five biscuits in a check-all-that-apply task, where half of the subjects (n = 87) evaluated the app ...
DOI:
10.1016/j.foodqual.2018.09.007

4. The development of a single-item Food Choice Questionnaire

Author:
Onwezen, M.C.; Reinders, M.J.; Verain, M.C.D.; Snoek, H.M.
Source:
Food quality and preference 2019 v.71 pp. 34-45
ISSN:
0950-3293
Subject:
variance,   etc   ; emotions; food choices; questionnaires;     Show all 4 Subjects
Abstract:
... Based on the multi-item Food Choice Questionnaire (FCQ) originally developed by Steptoe and colleagues (1995), the current study developed a single-item FCQ that provides an acceptable balance between practical needs and psychometric concerns. Studies 1 (N = 1851) and 2 (2a (N = 3290), 2b (N = 4723), 2c (N = 270)) showed that the single-item FCQ scale has good convergent and discriminant validity. ...
DOI:
10.1016/j.foodqual.2018.05.005

5. What's normal anyway? Residual plots are more telling than significance tests when checking ANOVA assumptions

Author:
Kozak, M.; Piepho, H.‐P.
Source:
Journal of agronomy and crop science 2018 v.204 no.1 pp. 86-98
ISSN:
0931-2250
Subject:
analysis of variance; variance,   etc   ; models;     Show all 3 Subject
Abstract:
... We consider two questions important for applying analysis of variance (ANOVA): Should normality be checked on the raw data or on the residuals (or is it immaterial which of the two approaches we take)? Should normality and homogeneity of variance be checked using significance tests or diagnostic plots (or both)? Based on two examples, we show that residuals should be used for model checking and th ...
DOI:
10.1111/jac.12220

6. A comparison study of meat eaters and non-meat eaters on mind attribution and moral disengagement of animals

Author:
Ang, Chin-Siang; Chan, Nee-Nee; Singh, Lavanya
Source:
Appetite 2019 v.136 pp. 80-85
ISSN:
0195-6663
Subject:
analysis of variance,   etc   ; humans; meat; pets;     Show all 4 Subjects
Abstract:
... This study aims to investigate how the distinction between animals that humans consume (AHCs) and pet animals influence meat eaters' and non-meat eaters’ perceived mind attribution on animals and moral disengagement. Following this, a two-way mixed ANOVA with repeated measures on the type of animals being slaughtered and type of eaters was conducted. For meat-eaters, perceived mental capacity rati ...
DOI:
10.1016/j.appet.2019.01.019

7. Impacts of stochastic forecast errors of renewable energy generation and load demands on microgrid operation

Author:
Chen, Yahong; Deng, Changhong; Yao, Weiwei; Liang, Ning; Xia, Pei; Cao, Peng; Dong, Yiwang; Zhang, Yuan-ao; Liu, Zhichao; Li, Dinglin; Chen, Man; Peng, Peng
Source:
Renewable energy 2019 v.133 pp. 442-461
ISSN:
0960-1481
Subject:
variance,   etc   ; energy; models; renewable energy sources;     Show all 4 Subjects
Abstract:
... Evaluating the impacts related to stochastic forecast errors (SFE) of renewable energy generation and load demands on the operation of micro grid is an important issue. In previous researches, the negative effects of SFE on micro grid are mainly focusing on power quality, system control, and operation, etc. The objective of this study is to investigate how SFE affects the operation stability of en ...
DOI:
10.1016/j.renene.2018.09.110

8. Stochastic modeling of oscillatory pumping in heterogeneous aquifers with application to Boise aquifer test

Author:
Cheng, Kan Bun; Rabinovich, Avinoam; Dagan, Gedeon
Source:
Journal of hydrology 2019 v.569 pp. 278-290
ISSN:
0022-1694
Subject:
variance,   etc   ; aquifers; piezometers; stochastic processes; uncertainty;     Show all 5 Subjects
Abstract:
... Oscillatory pumping tests consist of injecting periodic discharge into an aquifer and measuring head response along vertical piezometers surrounding the well. The aim is to identify the specific storativity s and conductivity K of the aquifer, which are generally spatially variable. Recently, an analytical solution for oscillating head in a homogeneous formation was derived and applied to the Bois ...
DOI:
10.1016/j.jhydrol.2018.11.045

9. Normalizing shadows in multi-temporal aerial frame imagery using relative radiometric adjustments to support near-real-time change detection

Author:
Storey, Emanuel Arnal; Stow, Douglas Alan; Plummer, Matthew James
Source:
GIScience & remote sensing 2019 v.56 no.1 pp. 22-42
ISSN:
1943-7226
Subject:
variance,   etc   ; radiometry; reflectance; regression analysis; remote sensing;     Show all 5 Subjects
Abstract:
... This study addresses the problem of shadows in multi-temporal imagery, which is a key issue with change detection approaches based on image comparison. We apply image-to-image radiometric normalizations including histogram matching (HM), mean-variance (MV) equalization, linear regression based on pseudo-invariant features (PIF-LR), and radiometric control sets (RCS) representing high- and low-refl ...
DOI:
10.1080/15481603.2018.1489446

10. Application of Passive Capillary Samplers in Water Stable Isotope Investigations of Snowmelt – A Case Study From Slovenia

Author:
Vreča, Polona; Brenčič, Mihael; Torkar, Anja
Source:
Vodohospodársky časopis 2019 v.67 no.1 pp. 32-40
ISSN:
0042-790X
Subject:
analysis of variance; variance,   etc   ; case studies; fiberglass; hydrogen; oxygen; samplers; snowmelt; stable isotopes; winter; Slovenia;     Show all 11 Subjects
Abstract:
... In this paper we describe the use of modified passive capillary samplers (PCSs) to investigate the water isotope variability of snowmelt at selected sites in Slovenia during winter 2011/2012 and during winter 2012/2013. First, PCS with 3 fibreglass wicks covering approximately 1 m2 were tested to determine sample variability. We observed high variability in the amount of snowmelt water collected b ...
DOI:
10.2478/johh-2018-0017

11. On mitigating the analytical limitations of finely stratified experiments Series B Statistical methodology

Author:
Fogarty, Colin B.
Source:
Journal of the Royal Statistical Society 2018 v.80 no.5 pp. 1035-1056
ISSN:
1369-7412
Subject:
variance,   etc   ; equations; models;     Show all 3 Subjects
Abstract:
... Although attractive from a theoretical perspective, finely stratified experiments such as paired designs suffer from certain analytical limitations that are not present in block‐randomized experiments with multiple treated and control individuals in each block. In short, when using a weighted difference in means to estimate the sample average treatment effect, the traditional variance estimator in ...
DOI:
10.1111/rssb.12290

12. The Use of Calibration Weighting for Variance Estimation Under Systematic Sampling: Applications to Forest Cover Assessment

Author:
Fattorini, Lorenzo; Gregoire, Timothy G.; Trentini, Sara
Source:
Journal of agricultural, biological, and environmental statistics 2018 v.23 no.3 pp. 358-373
ISSN:
1085-7117
Subject:
variance,   etc   ; forests; satellites; surveys;     Show all 4 Subjects
Abstract:
... The purpose of this note is to propose a variance estimator under non-measurable designs that exploits the existence of an auxiliary variable well correlated with the survey variable of interest. Under non-measurable designs, the Sen–Yates–Grundy variance estimator generates a downward bias that can be reduced using a calibration weighting based on the auxiliary variable. Conditions of approximate ...
DOI:
10.1007/s13253-018-0325-x

13. Nozzle effects on the injection characteristics of diesel and gasoline blends on a common rail system

Author:
Han, Dong; Zhai, Jiaqi; Duan, Yaozong; Wang, Chunhai; Huang, Zhen
Source:
Energy 2018 v.153 pp. 223-230
ISSN:
0360-5442
Subject:
variance,   etc   ; gasoline; mixing; nozzles;     Show all 4 Subjects
Abstract:
... In this study, the injection characteristics of diesel and blends of diesel and gasoline were investigated on a common rail injection system, using two nozzles with different orifice diameter and opening pressure. The volumetric injection rate curves, volumetric and mass cycle injection quantities and the coefficient of variances within a range of changed injection pressure and energizing time wer ...
DOI:
10.1016/j.energy.2018.04.039

14. Using Standard Tools From Finite Population Sampling to Improve Causal Inference for Complex Experiments

Author:
Mukerjee, Rahul; Dasgupta, Tirthankar; Rubin, Donald B.
Source:
Journal of the American Statistical Association 2018 v.113 no.522 pp. 868-881
ISSN:
1537-274X
Subject:
variance,   etc   ; equations; models; surveys;     Show all 4 Subjects
Abstract:
... This article considers causal inference for treatment contrasts from a randomized experiment using potential outcomes in a finite population setting. Adopting a Neymanian repeated sampling approach that integrates such causal inference with finite population survey sampling, an inferential framework is developed for general mechanisms of assigning experimental units to multiple treatments. This fr ...
DOI:
10.1080/01621459.2017.1294076

15. Improving Environmental Quality Through Aid: An Experimental Analysis of Aid Structures With Heterogeneous Agents

Author:
Chambers, Paul E.; Glenn Dutcher, E.; Mark Isaac, R.
Source:
Ecological economics 2018 v.146 pp. 435-446
ISSN:
0921-8009
Subject:
variance,   etc   ; ecosystems; environmental quality;     Show all 3 Subjects
Abstract:
... Environmental aid has grown significantly over the past decade with aid allocation mechanisms varying greatly and little guidance as to which should be preferred. To increase aid effectiveness, some have argued that potential recipients should compete for aid. We experimentally test this proposition against a baseline treatment where groups of heterogeneous agents receive aid by improving environm ...
DOI:
10.1016/j.ecolecon.2017.11.017

16. Comparison between the indirect approach and kriging with samples of different support for estimation using samples of different length

Author:
Bassani, MarcelAntonio Arcari; Costa, JoãoFelipe Coimbra Leite; Guaglianoni, WaleskaCampos; Rubio, RicardoHundelshaussen
Source:
Stochastic environmental research and risk assessment 2018 v.32 no.3 pp. 785-797
ISSN:
1436-3240
Subject:
variance,   etc   ; bauxite; databases; kriging;     Show all 4 Subjects
Abstract:
... In this paper we compare two estimation methods to deal with samples of different support: (1) the indirect approach using accumulation and (2) kriging with samples of different support. These two methods were tested in a simple example. The estimates of the two methods were compared against a benchmark scenario. The benchmark consisted of kriging using a complete set of samples on the same suppor ...
DOI:
10.1007/s00477-017-1398-8

17. From multiple Gaussian sequences to functional data and beyond: a Stein estimation approach Series B Statistical methodology

Author:
Koudstaal, Mark; Yao, Fang
Source:
Journal of the Royal Statistical Society 2018 v.80 no.2 pp. 319-342
ISSN:
1369-7412
Subject:
variance,   etc   ; equations; models; risk;     Show all 4 Subjects
Abstract:
... We expand the notion of Gaussian sequence models to n experiments and propose a Stein estimation strategy which relies on pooling information across experiments. An oracle inequality is established to assess conditional risks given the underlying effects, based on which we can quantify the size of relative error and obtain a tuning‐free recovery strategy that is easy to compute, produces model par ...
DOI:
10.1111/rssb.12255

18. Flow-Cell-Induced Dispersion in Flow-through Absorbance Detection Systems: True Column Effluent Peak Variance

Author:
Dasgupta, Purnendu K.; Shelor, Charles Phillip; Kadjo, Akinde Florence; Kraiczek, Karsten G.
Source:
Analytical chemistry 2018 v.90 no.3 pp. 2063-2069
ISSN:
1520-6882
Subject:
variance,   etc   ; absorbance; liquid chromatography;     Show all 3 Subjects
Abstract:
... Following a brief overview of the emergence of absorbance detection in liquid chromatography, we focus on the dispersion caused by the absorbance measurement cell and its inlet. A simple experiment is proposed wherein chromatographic flow and conditions are held constant but a variable portion of the column effluent is directed into the detector. The temporal peak variance (σₜ,ₒbₛ²), which increas ...
DOI:
10.1021/acs.analchem.7b04248

19. Building Hydrologic Foundations for Applications of ELOHA: How Long A Record Should You Have?

Author:
Williams, J. G.
Source:
River research and applications 2018 v.34 no.1 pp. 93-98
ISSN:
1535-1459
Subject:
variance,   etc   ; hydrology; uncertainty;     Show all 3 Subjects
Abstract:
... The Ecological Limits of Hydrologic Alteration framework for making regional assessments of environmental flows requires a ‘hydrologic foundation’ of flow data for current and undeveloped conditions. This raises the question how long a record is needed for an adequate hydrologic foundation? The answer depends on the variance in the flow record and on how much uncertainty is tolerable in metrics de ...
DOI:
10.1002/rra.3143

20. Investigation of the graphene thermal motion by rainbow scattering

Author:
Ćosić, M.; Hadžijojić, M.; Rymzhanov, R.; Petrović, S.; Bellucci, S.
Source:
Carbon 2019 v.145 pp. 161-174
ISSN:
0008-6223
Subject:
variance covariance matrix,   etc   ; anisotropy; graphene; molecular dynamics; protons;     Show all 5 Subjects
Abstract:
... The thermal motion of graphene atoms was investigated using angular distributions of transmitted protons. The static proton-graphene interaction potential was constructed applying the Doyle-Turner's expression for the proton-carbon interaction potential. The effects of atom thermal motion were incorporated by averaging the static proton-graphene interaction potential over the distribution of atom ...
DOI:
10.1016/j.carbon.2019.01.020