Table 9. Precision of estimate (P) at 95-pereent confidence 

 level for species per sample and abundance per 

 sample during Imperial Beach study. -^ 





Sample^ 

 (no.) 



Species 



per sample 



(pet) 



Individuals 



per sample 



(pet) 



INTERTIDAL 









3 transects 



90 



17.2 



26.9 



1 transect 



30 



26.9 



45.1 



3. 7-meter depth 



15 



13.9 



18.6 



6. 1-meter depth 



15 



14.0 



20,7 



^True population mean lies with ±P% of the sampled mean 

 95 percent of the time, assuming random distribution. 

 Most species per sample data fit a random description. 

 When data are contagiously distributed skewness of 

 precision estimates introduces an error term (see 

 Table 8). 



^Samples consisted of 500-milliliter cores; 8-centimeter 

 diameter x 10-eentimeter depth. 



50 



