From: The systematic sampling for inferring the survey indices of Korean groundfish stocks
Notation | Description |
---|---|
i | Grid cell. Each grid cell is divided into nine nested grids. See Fig. 1 for the location of grid cell i. |
s | Fish stock |
a _{ i} | The swept (trawled) area in grid cell i |
T _{ i} | The area of grid cell i. See Appendix Table 4 for the area of grid cell i. |
y _{ si} | Number (or weight) of fish stock s, caught by a standard trawl in one of the nine nested grids in grid cell i. This quantity is defined as the sampling unit. |
N | The total number of possible tows in the population area. |
Y _{ s} | The survey index (in number) of a fish stock s. |
B _{ s} | The survey index (in weight) of a fish stock s. |
d _{ si} | Differences between successive sampling units, i.e., d_{si} = y_{s, i + 1} − y_{si}. |
n | The number of the entire tows, which is the sample size. |
^ | In this paper, the hat notation is the expected value of a random variable, e.g., \( \widehat{Y_s}\equiv \)E{Y_{s}} |