While the basics of statistics start with cards or dice- where the number of possible outcomes is obvious…how the heck can we place odds on being struck by lightning, for example? How many possible outcomes are there? You might be tempted to base it on one out of thw world’s population…but this doesn’t account for all the possible spots on earth where lightning could strike (of which there is an infinite number of points). And, what about the odds of me just happening to be there at that very moment?
Very confusing! - Jinx 
Just a WAG, but it seems to me that statistics could be based on the number of lightning storms occuring during a given year vs. the number of persons struck/killed by lightning during the same year.
Basically it would go like this:
- There are X people living in America (or wherever);
- Of these, Y get struck by lightning in a given year;
- Any random person’s chances of getting struck by lightning in a given year are Y out of X.
- If you want to determine the chances of getting struck by lightning over the course of a lifetime, you’ll need to come up with an average lifespan. Let’s say it’s 70 years. The answer would be close to 70*Y/X, but not exactly because you need to take into consideration the possibility of an individual getting struck more than once.
Using the world’s population to figure the chances could be very misleading. Your chances of being struck would depend greatly where you were or what you were doing.
If you spend your time in Anchorage or Fairbanks, your chances of being struck is only slightly greater than having a tornado in the state, which since 1950 have been zero on the mainland.