I thought that 'pooling data' simply meant combining data that was previously split into categories...essentially, ignoring the categories and making the data set one giant 'pool' of data. I guess this is a question more about terminology than application of statistics.
For example: I want to compare 2 sites, and within each site I have two year-types (good and poor). If I want to compare the 2 sites 'overall' (that is, ignoring the year-types), is it correct to say that I'm pooling the data within each site? Further to that, since several years of data comprise the good and poor year-types, is it also correct to say that I am pooling the data among years to achieve the 'good year' and 'poor year' data set within each site?