The term was coined by Hurlbert (1984,p. 187) pseudoreplication to refer to "the use of inferential statistics to test for treatment effects with data from experiments where either treatments are not replicated (though samples may be) or replicates are not statistically independent." His paper concerned ecological field experiments, but pseudoreplication can occur in other fields as well. In this context, refers to having more than one replication experimental (or observational) unit with the same treatment. Each unit with the same treatment is called a replicate. There are other uses of the word replication -- for Note: example, repeating an entire experiment is also called replication; each repetition of the experiment is called a replicate. This meaning is related to the one given above: If each treatment in an experiment has the same number r of replicates (in the sense given above), then the experiment can be considered as r replicates (in the second sense) of an experiment where each treatment is applied to only one experimental unit. Heffner et al (1996, p. 2558) distinguish a pseudoreplicate from a which they characterize as true replicate, "the smallest experimental unit to which a treatment is independently applied." Most models for statistical inference require replication. true
The term pseudoreplication was coined by Hurlbert (1984,p. 187) to refer to "the use of inferential statistics to test for treatment effects with data from experiments where either treatments are not replicated (though samples may be) or replicates are not statistically independent." His paper concerned ecological field experiments, but pseudoreplication can occur in other fields as well. In this context, replication refers to having more than one experimental (or observational) unit with the same treatment. Each unit with the same treatment is called a replicate. Note: There are other uses of the word replication -- for example, repeating an entire experiment is also called replication; each repetition of the experiment is called a replicate. This meaning is related to the one given above: If each treatment in an experiment has the same number r of replicates (in the sense given above), then the experiment can be considered as r replicates (in the second sense) of an experiment where each treatment is applied to only one experimental unit. Heffner et al (1996, p. 2558) distinguish a pseudoreplicate from a true replicate, which they characterize as "the smallest experimental unit to which a treatment is independently applied." Most models for statistical inference require true replication.
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