If it's worth saying, but not worth its own post, then it goes here.
Notes for future OT posters:
1. Please add the 'open_thread' tag.
2. Check if there is an active Open Thread before posting a new one. (Immediately before; refresh the list-of-threads page before posting.)
3. Open Threads should start on Monday, and end on Sunday.
4. Unflag the two options "Notify me of new top level comments on this article" and "
I'll cross-post this from here because no-one responded and I'm still interested in an answer.
There is a question in this rationality test which goes like this:
They claim that the correct answer is "somewhat likely," arguing that the prize has fluctuated as much in past months as it did from September to October, therefore there is no strong evidence for the ads to have contributed. I think this is plain wrong, because
The way I see it, their explanation would possibly be correct if we only knew that there was a 50% probability that the ad campaign had taken place, and were to decide whether or not it did based on the results. But since we already know that it did take place, the correct answer seems to be "very likely."
Who is correct? The test or me? (I'm asking because if I'm wrong I really want to know why).
ok, there's not really enough data points to do proper stats but lets give it a go anyway.
Lets consider the possibility that the ad campaign did nothing. Some ad campaigns are actually damaging so lets try to get an idea of how much it varies from month to month.
Mean = 50.5 Standard Deviation = 6.05
So about 1 and 2/3rds SD's above the mean.
Sure, October is a little higher than normal but not by much.
Or put another way, imagine that the ad campaign had been put into effect in April but actually did absolutely nothing. They would have seen an increase o... (read more)