For four of the following five statements, indicate whether they are true or false, and why.

1. The main source of uncertainty in statistical analysis has to do with the difficulty of measurement; get that straight and little uncertainty remains.

2. The difference between experimental and observational data lies in whether or not special equipment is used to get more precise measurement.

3. If you can get enough observations on all the variables and types of cases you are interested in, and if it's feasible to implement, random assignment to treatment and control groups is the best strategy.

4. In an epidemic, where disease travels from one infected person to another, a power law distribution is likely to apply to counts of infections geographically and over time.

5. It is good practice to routinely eliminate all outliers, since they distort the distribution you're trying to measure.