Friday, April 8, 2011

May I Show You My Collection of p-Values?

Tom Thorn kindly sent me the following link, which is certainly pertinent to this posting: http://imgs.xkcd.com/comics/significant.png

It's always fun to start things off with a snap quiz - it wakes you up, if nothing else. So here we go - multiple choice, so you have at least a 20% chance of getting the correct answer:

Question:    Which of the following statements about p-values is correct?

1. A p-value of 5% implies that the probability of the null hypothesis being true is (no more than) 5%.
2. A p-value of 0.005 implies much more "statistically significant" results than does a p-value of 0.05.
3. The p-value is the likelihood that the findings are due to chance.
4. A p-value of 1% means that there is a 99% chance that the data were sampled from a population that's consistent with the null hypothesis.
5. None of the above.