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Full-Text Articles in Statistics and Probability
Exploring Multi-Year Soybean Yield Trial Data In South Dakota Environments, Jixiang Wu, Jianli Qi, Jonathan Kleinjan
Exploring Multi-Year Soybean Yield Trial Data In South Dakota Environments, Jixiang Wu, Jianli Qi, Jonathan Kleinjan
Conference on Applied Statistics in Agriculture
Crop performance test (CPT) is a common practice to evaluate yield performance and adaptability of each cultivar. In this study, we combined 16 years of soybean CPT data, which included six representative locations, three major maturity groups, and over 1000 cultivars, to determine some patterns associated with yield production. As expected, the repeatability for these cultivars in trial over years was very low. Thus, the data processing in this study was focused on descriptive statistics regarding time, location, and seed supplier and several linear model analyses. The results will be presented during the conference.
Modeling Potato Psyllid Occurrence Using Sticky Trap Data For The Management Of Zebra Chip Disease, William J. Price, Erik J. Wenninger, Bahman Shafii Ph.D.
Modeling Potato Psyllid Occurrence Using Sticky Trap Data For The Management Of Zebra Chip Disease, William J. Price, Erik J. Wenninger, Bahman Shafii Ph.D.
Conference on Applied Statistics in Agriculture
Zebra chip disease (ZC) is a disease of potato which produces striped necrotic patterns that become pronounced when fried, making potato products such as chips and fries unmarketable. The disease is associated with a bacterium Candidatus Liberibacter solanacearum (Lso) and is transmitted by the potato psyllid, Bactericera cockerelli. An important aspect in managing this disease is the modeling and prediction of potato psyllid occurrence. In this study, potato psyllid numbers were monitored regularly across the southern Idaho region. This unique data set encompasses psyllid counts, collected by multiple sticky traps, set up at 98 growing sites over the growing …
Evaluating Adaptions Of Soft Red Winter Wheat In Eastern Region Of Usa, Dilmini Alahakoon, Anne Fennell, Jixiang Wu
Evaluating Adaptions Of Soft Red Winter Wheat In Eastern Region Of Usa, Dilmini Alahakoon, Anne Fennell, Jixiang Wu
Conference on Applied Statistics in Agriculture
Identification of winter wheat cultivars that are highly adapted to a wide range of environmental conditions is one of the most important wheat research objectives. Multi-environment crop trials under diverse environments is a commonly used practice to evaluate yield stability. For example, uniform eastern and southern red soft winter wheat nursery trials are conducted annually. However, locations and cultivars may vary from year to year and may cause yield stability analysis to be statistically challenging. In this study, we evaluated cultivars that were widely adapted to eastern production areas and those that were specifically adapted to other environments. We used …
Effect Of Correlations On Type 1 Error Rates Of Some Multivariate Normality Tests, Gbenga Sunday Solomon, Kayode Ayinde, Nurudeen Abiodun Alao
Effect Of Correlations On Type 1 Error Rates Of Some Multivariate Normality Tests, Gbenga Sunday Solomon, Kayode Ayinde, Nurudeen Abiodun Alao
Conference on Applied Statistics in Agriculture
Normality assumption of multivariate data is a prerequisite to the use of multivariate statistical data analysis methods before inference could be valid and reliable. Tests developed to validate this assumption including Doornik-Harsen (DH), Shapiro-Francia (SF), Mardia Skewness (MS), Mardia Skewness for small sample (MSS) and Kurtosis (MK), Skewness (S) and Kurtosis(K), Shapiro-Wilk(SW), Royston (R), Desgagne-Micheaux (DM), Henze-Zirkler (HZ), Energy (E), Gel-Gastwirth (GG) and Bontemps-Meddahi (BM) tests often result into different conclusions. These differences can be misleading. Consequently, this paper examined the effect of correlations on the Type 1 error rates of multivariate tests of normality. Monte Carlo experiments were conducted …
Simulation Comparison Of Methods To Estimate Confidence Intervals Of The Mitigated Fraction, Kenneth W. Wakeland, Brian Fergen
Simulation Comparison Of Methods To Estimate Confidence Intervals Of The Mitigated Fraction, Kenneth W. Wakeland, Brian Fergen
Conference on Applied Statistics in Agriculture
In the area of veterinary medicine, efficacy studies are conducted to support licensure of vaccines. Such studies are typically designed to assess a vaccine's ability to prevent or mitigate clinical disease. For example, reduction of duration/severity of clinical signs or the severity of lung lesions are often considered as primary or secondary criteria of success. Studies designed to measure efficacy typically utilize two or more treatment groups and often use blocking structures to accommodate animal housing or litter related effects. When the criteria of interest are continuous or ordinal variables, as is the case with the above measurements, the mitigated …
Statistical Methods For Assessing Individual Oocyte Viability Through Gene Expression Profiles, Michael O. Bishop, John R. Stevens, S. Clay Isom
Statistical Methods For Assessing Individual Oocyte Viability Through Gene Expression Profiles, Michael O. Bishop, John R. Stevens, S. Clay Isom
Conference on Applied Statistics in Agriculture
In vivo derived oocytes are held as the gold standard for viability, other known origination methods are sub-par by comparison. Due to the low-viability of oocytes originating from these alternate methods, research was conducted to determine and quantify the validity of these alternate origination methods. However, the larger question of viability is on the individual oocyte level. We propose and compare methods of measurement based on gene expression profiles (GEPs) in order to assess oocyte viability, independent of oocyte origin. The first is based on a previously published wRMSD quantification of GEP differences. We also consider three novel methods: a …