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Solow's (1993) "Classical" model

SO93F1.Rd

Equation 2 from Solow 1993 (Equation 3 from Solow 2005), and Equations 4 and 5 from Solow 2005. Estimates a p-value for testing competing hypotheses of extinction/non-extinction, and a one-sided \(1 - \alpha\) confidence interval and point estimate on the time of extinction.

Usage

SO93F1(
  records,
  alpha = 0.05,
  init.time = min(records),
  test.time = as.numeric(format(Sys.Date(), "%Y"))
)

Arguments

records

sighting records in ccon format (see convert_dodo for details).

alpha

desired significance level (defaults to \(\alpha = 0.05\)) of the \(1 - \alpha\) confidence interval.

init.time

start of the observation period. Defaults to the time of the first sighting, in which case this sighting is removed from the record.

test.time

end of the observation period, typically the present day (defaults to the current year).

Value

a list object with the original parameters and the p-value, point estimate, and confidence interval included as elements. The confidence interval is a two-element numeric vector called conf.int.

Note

All sighting records are assumed to be certain and sampling effort is assumed to be constant.

References

Key Reference

Solow, A. R. (1993). Inferring Extinction from Sighting Data. Ecology, 74(3), 962-964. doi:10.2307/1940821

Other References

Solow, A., & Helser, T. (2000). Detecting extinction in sighting data. In S. Ferson & M. Burgman (Eds.), Quantitative methods for conservation biology (pp. 1-6). Springer-Verlag. doi:10.1007/b97704

Solow, A. R. (2005). Inferring extinction from a sighting record. Mathematical Biosciences, 195(1), 47-55. doi:10.1016/j.mbs.2005.02.001

Rivadeneira, M. M., Hunt, G., & Roy, K. (2009). The use of sighting records to infer species extinctions: an evaluation of different methods. Ecology, 90(5), 1291-1300. doi:10.1890/08-0316.1

See also

SO93B1()

Examples

# Run the Caribbean Monk Seal analysis from Solow 1993
SO93F1(monk_seal, test.time = 1992)
#> $records
#> [1] 1922 1932 1948 1952
#> 
#> $alpha
#> [1] 0.05
#> 
#> $init.time
#> [1] 1915
#> 
#> $test.time
#> [1] 1992
#> 
#> $p.value
#> [1] 0.05331433
#> 
#> $estimate
#> [1] 1961.25
#> 
#> $conf.int
#> [1] 1952.000 1993.245
#> 
if (FALSE) { # \dontrun{
# Run an example analysis using the Slender-billed Curlew data
SO93F1(curlew$ccon, init.time = 1817, test.time = 2022)
} # }