# Age-Based Survival and Mortality Estimators for Cluster Sampling

### Description

Calculates the survival and mortality estimators of Jensen (1996) where net hauls are treated as samples

### Usage

1 |

### Arguments

`age` |
the vector of ages. Each row represents the age of an individual. |

`group` |
the vector containing variable used to identify the sampling unit (e.g., haul). Identifier can be numeric or character. |

`full` |
the fully-recruited age. |

`last` |
the maximum age to include in the calculation. If not specified, the oldest age is used. |

### Details

The individual age data are tabulated and subsetted based on `full`

and `last`

. The calculations follow Jensen(1996).
If only two ages are present, a warning message is generated.

### Value

Matrix containing estimates of annual mortality (a), annual survival (S), and instantaneous total mortality (Z) and associated standard errors.

### Author(s)

Gary A. Nelson, Massachusetts Division of Marine Fisheries gary.nelson@state.ma.us

### References

Jensen, A. L. 1996. *Ratio estimation of mortality using catch curves*. Fisheries Research 27: 61-67.

### See Also

`agesurv`

### Examples

1 2 |