The study of normal galaxies will remain exciting because of, and in spite of,
the complexities and bewildering abundance of data and correlations.
A few suggestions might
help in navigating these complexities:
- In statistical studies,
it is critical to understand the sample being used, its biases
- The questions to pursue should be physical rather than statistical
in nature. The latter will flow from the former, but should not
- Quantities studied, statistically or in detail, should have
clear physical significance. Distance-independent ``intensive'' quantities are
preferable to luminosities or similarly scaling extensive parameters.
- In constructing quantities from observables, one should avoid
complex parameters with multiple built-in assumptions, such as dust mass
which combines a flux with an uncertain color temperature taken to a power
of 5 or so.