COMPARATIVE STATISTICAL ANALYSIS OF PRIMARY AND SECONDARY DATA OF FISH CAGES IN DAMIETTA
AND ROSETTA BRANCHES, EGYPT
Abdel-Hady, M.M1; A.F.M El-Sayed2;
S.M. Haggag3 and S.A. Hashem1
1Institute of Environmental Studies And Researsh , Ain Shams University.
2Faculty of science, Alexandria University.
3National Institute For Oceanography and Fisheries, Alexandria.
Abstract
This study aimed to compare the fish cages data in Damietta and Rosetta branches in each of the statistics issued by the General Authority for Fisheries Development (secondary data) and a random sample of fish cages (primary data) which were consisted of 658 cages for the 2014 season through a questionnaire. The study was based on descriptive statistical analysis. It’s concluded that there is a clear discrepancy between the primary and secondary data of the fish cages. For example, the average size of the cage was 1284 and 250 m3 in both primary and secondary data respectively in Damietta Governorate. The production volume was about 4. 6 and 10 tons/cage in both primary and secondary data respectively in Kafr El-Sheikh governorate. The average of production kg/m3 in cages at El-Beheira governorate was about 4,1 and 171,2 kg/m3 in both primary and secondary data, respectively. As for the species in the Rosetta branch behind archways, Tilapia production was about 27% and 100%, and Mugilidae species
were about 73% and 0% in both primary and secondary data respectively. As fish prices also were varied, the price of carp was 2,7 and 16 LE/kg in both primary and secondary data respectively, and no cages were observed in El-Gharbia Governorate in secondary data, although its high cages productivity compared to other governorates as shown by the primary data. Thus, reliance on secondary data may lead to incorrect decisions and results. So, this study suggests some possible frameworks for improving the quality of statistics.
