Crop production data and forecasts system in ... - Foodnet - cgiar

sampling methods to generate national production estimates disaggregated into four
regions of Uganda (Annex 2).
Coefficients of variation (CVs) are used in the 1999 / 2000 report to evaluate data
reliability with CVs higher than 20% seen as unattractive. Estimated CVs given in the
crop module report show that ‘at the national level coefficients of variation are
generally low indicating that the estimates are precise’ (UBOS Crop Survey Module
2000).
Key informants view Crop Survey statistics as credible. Crop surveys show greater
consistency with production statistics produced by other organisations. The 1999 /
2000 Crop Survey module represents a valuable resource for determination of
baseline crop production.
5.2 FAO Data
The FAO rely on data supplied by MAAIF and UBOS. FAO production statistics are
thus exposed to the same caveats that blight MAAIF / UBOS data.
5.3 IDEA Project Data
The IDEA project produces seasonal production statistics and monthly import and
export figures for maize and beans. Export data is also available for matooke cooking
bananas to international markets.
Production forecasts are produced for maize and bean crops.
5.3.1 Forecasting District and National Maize and Bean Production
Maize and bean forecasts focus on districts covered by the IDEA project. Crop
specialists who have a detailed local knowledge of the districts covered produce the
forecasts. Hectare estimates are based on UBOS / MAAIF crop area data from 1981
to 1996. These area estimates are adjusted according to recent field observation giving
an estimate of current area planted by district. Project crop specialists regularly assess
field conditions when they visit the relevant districts. The area planted figure is
multiplied by a yield estimate to give a forecast of production. The IDEA Project crop
specialist determines the yield estimate based on recent field observation. To achieve
a national figure district figures are summed, estimates for districts falling outside of
the IDEA project rely on historic UBOS / MAAIF data.
The IDEA staff themselves view the district and national level production statistics
for maize and beans as insufficiently accurate. Accuracy is particularly lost through
the estimation of crop area. The project has tried physically measuring crop areas with
tape measures but found this impractical. National figures include production from
districts where the actual situation is little known. Traders interviewed confirmed the
view that IDEA national production figures are insufficiently accurate. It is however
generally perceived that the IDEA national production estimates are generally more
reliable than current monthly UBOS / MAAIF statistics.
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