@article{oai:oacis.repo.nii.ac.jp:00002449,
 author = {田中, 栄次},
 issue = {2},
 journal = {日本水産学会誌, Nippon Suisan Gakkaishi},
 month = {Mar},
 note = {定置網漁業におけるクロマグロの割当量の5つの管理方式の性能をシミュレーションで検討した。
管理方式は1）月別県別管理，2）月別共同管理，3）年別県別管理（現状），4）年別共同管理，5）月間県別割当量の緩和措置である。
年間漁獲量の確率分布を多変量対数正規分布で，月別漁獲量の割合をディリクレ分布で表した。基本シナリオの結果では割当量の達成率の期待値はそれぞれ78，87，91，99，90%であった。実用化の課題等について議論した。, An investigation was carried out using simulation models in order to compare the performance of five proce dures for controlling the quota of set net fisheries exploiting the stock of the Pacific bluefin tuna Thunnus orienta lis under fluctuating environments. 
To account for correlations in annual catches among prefectures, a multivari ate lognormal distribution was assumed as the probability density function. Also, a Dirichlet distribution was used for expressing the difference in proportion of monthly catch to the annual catch over prefectures. The annual quo ta is controlled by the following five procedures: monthly and prefectural quota (P1), monthly quota without prefectural regulation (P2), annual and prefectural quota (P3), annual quota without any other regulation (P4) and monthly and prefectural quota with allowance (P5). 
Twenty thousand simulations using random numbers were iterated to evaluate the performance in mean and variance for each of the procedures under several scenar ios. The results in the base case scenario showed that the expected rate of achieved catch to annual quota for P1-P5 were 78, 87,91, 99 and 90%, respectively. Issues involved in the practice of the procedures and modifications of the models are discussed.},
 pages = {48--58},
 title = {定置網漁業におけるクロマグロの割当量の管理方式について},
 volume = {86},
 year = {2020}
}