Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields
Measuring yield accurately is critical for evaluating the impact of interventions that aim to increase agricultural productivity but presents challenges in the case of coffee due to the long harvest period. An allometric approach, in which the fruits on randomly selected branches and clusters are co...
| Autores principales: | , , , , , |
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| Formato: | Artículo preliminar |
| Lenguaje: | Inglés |
| Publicado: |
International Food Policy Research Institute
2021
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| Materias: | |
| Acceso en línea: | https://hdl.handle.net/10568/143441 |
| _version_ | 1855521376480264192 |
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| author | Hoffmann, Vivian Murphy, Mike Rwakazooba, Ezra Angebault, Charles Kagezi, Godfrey Zane, Giulia |
| author_browse | Angebault, Charles Hoffmann, Vivian Kagezi, Godfrey Murphy, Mike Rwakazooba, Ezra Zane, Giulia |
| author_facet | Hoffmann, Vivian Murphy, Mike Rwakazooba, Ezra Angebault, Charles Kagezi, Godfrey Zane, Giulia |
| author_sort | Hoffmann, Vivian |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | Measuring yield accurately is critical for evaluating the impact of interventions that aim to increase agricultural productivity but presents challenges in the case of coffee due to the long harvest period. An allometric approach, in which the fruits on randomly selected branches and clusters are counted is widely used due to its non-destructive nature and acceptability to farmers. However, this approach requires careful attention to detail, which may be difficult to maintain in the context of large-scale data collection efforts. Using data from 199 small-scale Robusta coffee farms in Uganda, we compare yield estimates obtained through a standard allometric protocol against those from a one-time harvest of both ripe and unripe cherries prior to the start of the harvest season. The one-time harvest method was widely acceptable to farmers. Allometric yield estimates explain just under half of the variation in the harvest-based yield measure. While estimated yield is similar across methods for the first tree harvested per farm, we observe a larger difference in allometric versus harvest-based estimates, and systematically lower counts of stems and branches for trees assessed later during the farm visit. We interpret these findings as evidence of deteriorating enumerator performance on the allometric method over time, implying a risk of downward-biased yield estimates. |
| format | Artículo preliminar |
| id | CGSpace143441 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2021 |
| publishDateRange | 2021 |
| publishDateSort | 2021 |
| publisher | International Food Policy Research Institute |
| publisherStr | International Food Policy Research Institute |
| record_format | dspace |
| spelling | CGSpace1434412025-12-02T21:03:24Z Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields Hoffmann, Vivian Murphy, Mike Rwakazooba, Ezra Angebault, Charles Kagezi, Godfrey Zane, Giulia methods agricultural extension training measurement yield components agriculture allometry yields coffee enumeration impact assessment Measuring yield accurately is critical for evaluating the impact of interventions that aim to increase agricultural productivity but presents challenges in the case of coffee due to the long harvest period. An allometric approach, in which the fruits on randomly selected branches and clusters are counted is widely used due to its non-destructive nature and acceptability to farmers. However, this approach requires careful attention to detail, which may be difficult to maintain in the context of large-scale data collection efforts. Using data from 199 small-scale Robusta coffee farms in Uganda, we compare yield estimates obtained through a standard allometric protocol against those from a one-time harvest of both ripe and unripe cherries prior to the start of the harvest season. The one-time harvest method was widely acceptable to farmers. Allometric yield estimates explain just under half of the variation in the harvest-based yield measure. While estimated yield is similar across methods for the first tree harvested per farm, we observe a larger difference in allometric versus harvest-based estimates, and systematically lower counts of stems and branches for trees assessed later during the farm visit. We interpret these findings as evidence of deteriorating enumerator performance on the allometric method over time, implying a risk of downward-biased yield estimates. 2021-12-03 2024-05-22T12:14:10Z 2024-05-22T12:14:10Z Working Paper https://hdl.handle.net/10568/143441 en https://doi.org/10.2499/p15738coll2.133570 https://doi.org/10.2499/p15738coll2.134836 https://doi.org/10.2499/p15738coll2.134408 Open Access application/pdf International Food Policy Research Institute Hoffmann, Vivian; Murphy, Mike; Rwakazooba, Ezra; Angebault, Charles; Kagezi, Godfrey; and Zane, Giulia. 2021. Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields. IFPRI Discussion Paper 2065. Washington, DC: International Food Policy Research Institute (IFPRI). https://doi.org/10.2499/p15738coll2.134844. |
| spellingShingle | methods agricultural extension training measurement yield components agriculture allometry yields coffee enumeration impact assessment Hoffmann, Vivian Murphy, Mike Rwakazooba, Ezra Angebault, Charles Kagezi, Godfrey Zane, Giulia Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields |
| title | Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields |
| title_full | Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields |
| title_fullStr | Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields |
| title_full_unstemmed | Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields |
| title_short | Enumerator bias in yield measurement: A comparison of harvest versus allometric measurement of coffee yields |
| title_sort | enumerator bias in yield measurement a comparison of harvest versus allometric measurement of coffee yields |
| topic | methods agricultural extension training measurement yield components agriculture allometry yields coffee enumeration impact assessment |
| url | https://hdl.handle.net/10568/143441 |
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