Next / Previous / Shipman's Home Sweet Homepage / Site map

CBC Compilers: The High Count (HC) flag

You should flag a species as high-count if its numbers are more than two standard deviations above the mean. For example, if the mean count for a species is 50 and the standard deviation is 60, you should flag as HC any records greater than 170 (that is, 50 + 60*2).

There are two exceptions to this general rule:

In general, your judgement should take precedence over blind obedience to the statistical rule. If you feel that a given species has not increased despite increases in observed numbers, don't flag it. Conversely, if you think a species is significantly more numerous in the current year, flag it as HC even if it doesn't pass the test.

Next: CBC Compilers: The Unusual Species (US) flag
See also: Christmas Bird Counts in New Mexico
Site map
John W. Shipman,
Last updated: 2000/05/04 18:20:24