author = "Pitaluga, Elvira N{\'o}brega and Rocha, Regina Celia Larangeira 
                         and Silva, Vilma Sirimarco Monteiro da",
          affiliation = "{Instituto Brasileiro de Geografia e Estat{\'{\i}}stica (IBGE). 
                         Diretoria de Geoci{\^e}ncias.} and {Instituto Brasileiro de 
                         Geografia e Estat{\'{\i}}stica (IBGE). Diretoria de 
                         Geoci{\^e}ncias.} and {Instituto Brasileiro de Geografia e 
                         Estat{\'{\i}}stica (IBGE). Diretoria de Geoci{\^e}ncias.}",
                title = "Painel de amostras de {\'a}reas para pesquisa agropecu{\'a}ria 
                         do Estado de S{\~a}o Paulo",
            booktitle = "Anais...",
                 year = "1993",
               editor = "Cunha, Roberto Pereira da and Dias, Luiz Alberto Vieira",
                pages = "233--238",
         organization = "Simp{\'o}sio Brasileiro de Sensoriamento Remoto, 7. (SBSR).",
            publisher = "Instituto Nacional de Pesquisas Espaciais (INPE)",
              address = "S{\~a}o Jos{\'e} dos Campos",
             abstract = "The Crop Forecasting Project is part of the program for 
                         improvement the brazilian agricultural statistical data. Its main 
                         objective is to improve the quality of the data needed for 
                         planning the agricultural sector in the country. This Project has 
                         been trying to establish an efficient data collection system based 
                         upon an stratified area sample design. The frame from where the 
                         sample is selected was constructed according to a land use 
                         stratification methodology, which subdivided the frame into count 
                         units and segments (sample unit), with the use of visual 
                         interpretation techniques, data analysis and cartographic 
                         documentation. Because of its versatility the area sampling frame 
                         is considered basic for the selection of sample of segments. Its 
                         main objective is to simplify the process of determination the 
                         sample units, allowing that the investigation of the sample data 
                         be done in a very efficient way, increasing the precision of its 
                         results. The survey which has been carried on since ] 987, 
                         includes the Distrito Federal and the States of Paran{\'a}, Santa 
                         Catarina and S{\~a}o Paulo. Because it was the last work done, 
                         the sampling frame constructed for the State of S{\~a}o Paulo 
                         incorporated all of the methodological experience acquired on this 
                         period and that's was the reason for choosing for presentation. 
                         Among others changes it is possible to emphasize that for the 
                         first time it was treated separately big fields from small ones in 
                         the agricultural strata with the aim of enhancing the farming 
                         structuring. Ali of the stratification work was done in a 
                         municipal basis and because of that the data collection 
                         supervisors were asked to draw on municipios maps the spacial 
                         distribution of crops in each particular area of work. Appart from 
                         that field trips for data checking were done with the objective of 
                         identifying spectral signatures on sattelite images, scale 1: 
                         100.000, color composition, channels 3, 4 and 5 with blue, green 
                         and red filters, respectively. With this methodology it was 
                         possible to define the strata according to the intensity use of 
                         the agriculture, pasture or forest land. The field work consisted 
                         on the investigation of 658 sample segments, with the sample 
                         allocated to the strata according to probability proportion to the 
                         size of the stratum (number of segments). The principIes variables 
                         investigated during the two years where the survey was carried on 
                         were: planted area; to be planted and harvested area, including 
                         the obtained and expected yield for 13 principal crops in the 
                         State of S{\~a}o Paulo. International experience has been proved 
                         that this system of data collection is the most effective when 
                         considering time, costs and precision of results.",
  conference-location = "Curitiba",
      conference-year = "10-14 maio 1993",
                 isbn = "978-85-17-00055-3",
             language = "pt",
         organisation = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                  ibi = "dpi.inpe.br/marte@80/2008/",
                  url = "http://urlib.net/rep/dpi.inpe.br/marte@80/2008/",
           targetfile = "233-238.pdf",
                 type = "Monitoramento e Invent{\'a}rio de Recursos Renov{\'a}veis e Meio 
               volume = "4",
        urlaccessdate = "18 jan. 2021"