Converts parameter specification from vector or list format
convert_param(param, cells_w, cells_b, type = "this parameter")
| param | the parameter (mu, sd, or n) |
|---|---|
| cells_w | a list of within-subject cells combinations |
| cells_b | a list of between-subject cell combinations |
| type | the name of the parameter (for error messages) |
a list of parameters