8.3.3 Describe briefly the results of comparisons |
Results should be expressed as percentage deviation from the corresponding areas in the orchard survey.
|
Annual Crop Statistics (2017) |
FSS (2016) |
IACS 2015 |
Other source |
Dessert apple trees |
2,6 |
2,4 |
Not applicable |
|
Apple trees for industrial processing |
Not applicable |
Not applicable |
Not applicable |
|
Dessert pear trees |
10,9 |
-8,4 |
-2,2 |
|
Pear trees for industrial processing |
Not applicable |
Not applicable |
Not applicable |
|
Apricot trees |
0,5 |
-2,4 |
-5,5 |
|
Dessert peach and nectarine trees |
23,7 |
3,9 |
-1,4 |
|
Peach and nectarine trees for industrial processing (including group of Pavie) |
Not applicable |
Not applicable |
Not applicable |
|
Orange trees |
6,9 |
0,9 |
Not applicable |
|
Small citrus fruit trees |
32,7 |
9,8 |
Not applicable |
|
Lemon trees |
50,4 |
-25,4 |
Not applicable |
|
Olive trees |
9,3 |
-3,5 |
2,2 |
|
Table grape vines |
10,6 |
13,0 |
-1,2 |
|
The differences between the results of the Permanent crops survey and other statistical sources (ACS, FSS 2016, IACS) are mainly due to: 1- differences in definitions, reference period, statistical unit, etc.; 2- different technique of data collection; 3- different scope of data collection. As regards ACS, the most important source of discrepancies is the difference between the data collection methods: the Orchard Survey is a sample survey based on direct interviews to the holdings, while ACS is based on experts elicitation and/or on the IACS data (on average, for the 50% of Italian Regions). Moreover, the Orchards data collection includes only the data on farms producing mostly for the market and very small holdings are cut off from the observation. Two different statistical surveys, even though referred to similar domains, cannot produce the same results. The use of calibration techniques (which as a matter of fact has not been adopted for Italian agriculture statistics with regards to ACS) would be misleading, because the use of ACS constraints for producing estimated totals derived from Orchard would solve problems only apparently. As already stated in other contexts, we do not consider a good practice the use of short-term surveys (e.g., infra-annual measurements) as ACS are for structural analysis purposes: that is not done in any other context – as business statistics – since it is well known that precision of structural surveys (as Orchard) should always be higher than short-term, which however are available in advance. As regards FSS: even if both Surveys on permanent crops and FSS are based on a sample survey, the constrains adopted to draw the sample (and the holdings) are very different, since two different Regulations rule the surveys. In particular, FSS constrains concern structural variables of the holding (UAA, UBA, and other aggregated variables), which are different from the target variables of permanent crops statistics, so that the accuracy level for permanent crops should be larger in Orchard than in FSS. Moreover, the reference period is different. As regards the administrative data (IACS): at the moment data are not available for some species because they belong to very aggregated items (for example, the total area cultivated for Citrus tree is present, but it is not available the breakdown into the different species). Where the comparison is possible, the results appear consistent, considering the different scope of the data collections and the different reference periods. 2012: In FSS only main crop area has to be surveyed. In ACS also secondary and successive crop area are counted. But the most important source of discrepancies (explaining also the case of ACS data bigger than Orchard Survey) are the two different methods of data collection: Orchard Survey is a sample survey based on direct interviews to the holdings, while ACS is based on experts elicitation. |