# Calculates the raw Visual Fast Count (VFC) estimator of the mean abundance per transect

### Description

The function considers the counts per segment and uses them sequentially until `d`

positive counts
are obtained or until all `s`

segments have been considered. If we assume that `u`

counts are used (of
which some may be zero) then
the visual fast count estimator is the mean over the `u`

counts multiplied by `s`

. This function is used
by `GVFCMOM`

to obtain the method of moments VFC estimator - which has reduced bias compared to the
raw VFC estimator.

### Usage

1 | ```
GVFC(counts, s, d)
``` |

### Arguments

`counts` |
Vector of length s that contains a count for each segment |

`s` |
Number of segments |

`d` |
Number of positive segment counts needed before counting stops |

### Value

The raw VFC estimate of the segment mean

### Author(s)

Jon Barry: jon.barry@cefas.co.uk

### References

Barry J, Eggleton J, Ware S and Curtis M (2015) Generalizing Visual Fast Count Estimators for Underwater Video Surveys. Ecosphere. http://www.esajournals.org/doi/full/10.1890/ES15-00093.1

### See Also

`GVFCMOM`