type of test

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type of test
Message posted by Thomas Lera on August 10, 2000 at 12:00 AM (ET)

Lets say you are looking at postage stamps from 100 different countries. The common element is that all of the stamps have various pictures of , lets say, bats or flying foxes depicted on them. What type of tests would be suitable to run if you wanted to quantify those with certain species, certain characteristics like flying, roosting, etc., country/continent comparison.
Thanks for the help.

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Re: type of test
Message posted by nancy diehl on August 11, 2000 at 12:00 AM (ET)

My suggestion is as follows: Create a two way classification table where one classification is Country (this
classification may need to be collapsed into Continent because of too many Countries), and the other classification
is specie type (you may also want to create a separate classification and replace specie type with characteristic).
Now classify these stamps in the table so the cells represent counts of occurrences. You would apply a Chi-Square
test testing the null hypothesis for independence between the two classification types (i.e. the type of specie on the stamp
is independent of the Continent in which the stamp comes from). However, you have to be careful with this test due to
small expected frequencies (less than 5) can inflate the test statistic and provide erroneous results.
In this case, the Fisher Exact test should be applied.

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