Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationships
In recent years, linear mixed models (LMM) have become more popularto deal with spatial effects in forestry and ecological data. In this study, different structure specifications of linear mixed model were applied to model tree height-diameter relationships, including LMM with random blocks only (LM...
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| Format: | Article |
| Language: | English |
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‘Marin Drăcea’ National Research-Development Institute in Forestry
2013-05-01
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| Series: | Annals of Forest Research |
| Subjects: | |
| Online Access: | http://www.editurasilvica.ro/afr/56/1/lu.pdf |
| _version_ | 1811215625808248832 |
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| author | Junfeng Lu Lianjun Zhang |
| author_facet | Junfeng Lu Lianjun Zhang |
| author_sort | Junfeng Lu |
| collection | DOAJ |
| description | In recent years, linear mixed models (LMM) have become more popularto deal with spatial effects in forestry and ecological data. In this study, different structure specifications of linear mixed model were applied to model tree height-diameter relationships, including LMM with random blocks only (LMM-block), LMM with spatial covariance only (LMM-covariance), and the combination of the last two (LMM-block-covariance). Further, the between group heterogeneous variances were incorporated into LMM-covariance and LMM-block-covariance. The results indicated that, in general, LMM-covariance significantly reduced spatial autocorrelation in model residuals, while LMM-block was effective in dealing with spatial heterogeneity. LMM-blocktreated the blocks as random effects and avoided the estimation of parameters of the variogram model. Thus, it produced better model predictions than LMM-covariance. LMM-block-covariance took both block effects and spatial covariance into account, and significantly improve model fitting. However, it did not produce better model predictions due to the increase of model complexity and estimation of the local variogram within each block. |
| first_indexed | 2024-04-12T06:26:52Z |
| format | Article |
| id | doaj.art-4f093f25bb394ecd9f2e2fa462b1e420 |
| institution | Directory Open Access Journal |
| issn | 1844-8135 2065-2445 |
| language | English |
| last_indexed | 2024-04-12T06:26:52Z |
| publishDate | 2013-05-01 |
| publisher | ‘Marin Drăcea’ National Research-Development Institute in Forestry |
| record_format | Article |
| series | Annals of Forest Research |
| spelling | doaj.art-4f093f25bb394ecd9f2e2fa462b1e4202022-12-22T03:44:08Zeng‘Marin Drăcea’ National Research-Development Institute in ForestryAnnals of Forest Research1844-81352065-24452013-05-01561137148Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationshipsJunfeng LuLianjun ZhangIn recent years, linear mixed models (LMM) have become more popularto deal with spatial effects in forestry and ecological data. In this study, different structure specifications of linear mixed model were applied to model tree height-diameter relationships, including LMM with random blocks only (LMM-block), LMM with spatial covariance only (LMM-covariance), and the combination of the last two (LMM-block-covariance). Further, the between group heterogeneous variances were incorporated into LMM-covariance and LMM-block-covariance. The results indicated that, in general, LMM-covariance significantly reduced spatial autocorrelation in model residuals, while LMM-block was effective in dealing with spatial heterogeneity. LMM-blocktreated the blocks as random effects and avoided the estimation of parameters of the variogram model. Thus, it produced better model predictions than LMM-covariance. LMM-block-covariance took both block effects and spatial covariance into account, and significantly improve model fitting. However, it did not produce better model predictions due to the increase of model complexity and estimation of the local variogram within each block.http://www.editurasilvica.ro/afr/56/1/lu.pdflinear mixed modelspatial heterogeneityspatial auto-correlationheight-diameter equation. |
| spellingShingle | Junfeng Lu Lianjun Zhang Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationships Annals of Forest Research linear mixed model spatial heterogeneity spatial auto-correlation height-diameter equation. |
| title | Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationships |
| title_full | Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationships |
| title_fullStr | Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationships |
| title_full_unstemmed | Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationships |
| title_short | Evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height-diamater relationships |
| title_sort | evaluation of structure specification in linear mixed models for modeling the spatial effects in tree height diamater relationships |
| topic | linear mixed model spatial heterogeneity spatial auto-correlation height-diameter equation. |
| url | http://www.editurasilvica.ro/afr/56/1/lu.pdf |
| work_keys_str_mv | AT junfenglu evaluationofstructurespecificationinlinearmixedmodelsformodelingthespatialeffectsintreeheightdiamaterrelationships AT lianjunzhang evaluationofstructurespecificationinlinearmixedmodelsformodelingthespatialeffectsintreeheightdiamaterrelationships |