Application of Linear Mixed Model to Incomplete Block Designs
| dc.contributor.advisor | Taye, Girma (PhD) | |
| dc.contributor.author | Lakew, Demeke | |
| dc.date.accessioned | 2022-03-30T08:47:51Z | |
| dc.date.accessioned | 2023-11-09T14:29:28Z | |
| dc.date.available | 2022-03-30T08:47:51Z | |
| dc.date.available | 2023-11-09T14:29:28Z | |
| dc.date.issued | 2010-06 | |
| dc.description.abstract | The study was designed to examine th e application of linear mixed model to incomplete block designs. In addition to thi s, it is planned to compare VARCOMP, ML and REML estimation methods for variance components of linear mixed models. Sixty three promising bar ley lines and one standard check cultivar which were obtained from EIAR have been evaluated for grain yield performance and adaptation across eight environments (combination offour lo cations by two ferti lizers). The mean grain yields for individual line ranged from 17.06 to 33.21 quintals per hectare and the mean grain yields for in dividual environment ranged from 16.80 to 44.214 quintals per hectare. The highest mean grain yield was observed at BEKOjl, while the lowest mean grain yield was registe red at SHENO with both fertilizers doses (100 and 150 kg). When we compare each variety with specific environment, lin e 8 and 55, Variety 20 and 14, Variety 49 and 54 and Variety 48 and the Local check to be ada pted and have best mean effects to BEKOJI, SHENO, HOLETTA and NORTH GONDAR respectively. KEML estimates for vari a nce components are in distinguishable from classical techniques in case of balanced data. This im pl ies optimal minimum variance properties and REML estimates do not rely on normality assumption. But, for unbalanced data, the REML estimation for variance components is different from classical estimates. We have seen from the diffe rences that estimation of variance components benefits from REML bu t VARCOMP does not. Therefore, the REML approach is appropriate to estimate va riance components in SLD and SLD with missing plots. Varieties/lines listed above were recommended to release in Ethiopia that have similar ecologic zones of respective location s and REML techniques was recommended to be used for va riance components esti mates of linear mixed model for SLD and SLD with missing plots. It was found that diagnostics for Linear Mixed Model applied to estim ate variance components are perh aps an area that needs exploration in the future. | en_US |
| dc.identifier.uri | http://10.90.10.223:4000/handle/123456789/31007 | |
| dc.language.iso | en | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Application of Linear Mixed Model | en_US |
| dc.title | Application of Linear Mixed Model to Incomplete Block Designs | en_US |
| dc.type | Thesis | en_US |