Basic Definitions Used in Community Analyses
369
One can determine the relative sampling cost (efficiency) by recording the average
time required to collect the information at a given sampling point. Do this by recording
the minutes (or days) required to obtain a given number of samples. The sample size
should be reasonably large and taken under realistic conditions, since fatigue and
environmental conditions (such as blistering sun, biting insects, and rough terrain)
influence the rapidity with which data can be taken. Divide the sampling time by the
number of sampling units needed to provide a sample of specified adequacy. This value
represents the relative cost that is necessary to obtain the kind of information sought.
Comparisons will demonstrate that all sizes, shapes, and methods of quadrat
placement are not equally economical.
References
Elliott, 1M. 1977. Some Methods for the Statistical Analysis of Samples of Benthic Invertebrates.
2nd Ed. Sci. Publ. Freshwat. BioI. Assoc. u.K. 25. 156pp.
Siegal, S. 1956. Nonparameteric Statistics for the Behavioral Sciences. McGraw-Hill, New York.
312pp.
Rohlf, F.J. and R.R. Sokal. 1981. Statistical Tables. Freeman, San Francisco.
Sokal, R.R. and F.J. Rohlf. 1981. Biometry. The Principles and Practice of Statistics in Biological
Research. Freeman, San Francisco. 859 pp.
369
One can determine the relative sampling cost (efficiency) by recording the average
time required to collect the information at a given sampling point. Do this by recording
the minutes (or days) required to obtain a given number of samples. The sample size
should be reasonably large and taken under realistic conditions, since fatigue and
environmental conditions (such as blistering sun, biting insects, and rough terrain)
influence the rapidity with which data can be taken. Divide the sampling time by the
number of sampling units needed to provide a sample of specified adequacy. This value
represents the relative cost that is necessary to obtain the kind of information sought.
Comparisons will demonstrate that all sizes, shapes, and methods of quadrat
placement are not equally economical.
References
Elliott, 1M. 1977. Some Methods for the Statistical Analysis of Samples of Benthic Invertebrates.
2nd Ed. Sci. Publ. Freshwat. BioI. Assoc. u.K. 25. 156pp.
Siegal, S. 1956. Nonparameteric Statistics for the Behavioral Sciences. McGraw-Hill, New York.
312pp.
Rohlf, F.J. and R.R. Sokal. 1981. Statistical Tables. Freeman, San Francisco.
Sokal, R.R. and F.J. Rohlf. 1981. Biometry. The Principles and Practice of Statistics in Biological
Research. Freeman, San Francisco. 859 pp.