Between three and nine independent experiments were conducted using identical dosing ranges for amantadine, ribavirin, and oseltamivir carboxylate against each virus. The experiments used a 3-replicate plate format, for a total of 9 to 27 observations for each condition. The data from the independent experiments were merged and subjected to statistical analysis using the random effects model. The raw data were imported into the program R and were normalized to the virus and cell controls as described above, and synergy (percent inhibition above calculated) is calculated as above. For synergy volume estimates, random effects models were applied to the data to account for variation between replicate measures within experiments. Therefore, the models took the form as given by: