Page 46 - Statistics for Dummies

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Part I: Vital Statistics about Statistics
your umbrella to work, but they also help weather researchers to better pre-
dict longer term forecasts and even global climate changes over time.
Even with all the information and technologies available to weather research-
ers, how accurate are weather reports these days? Given the number of times
you get rained on when you were told it was going to be sunny, it seems they
still have work to do on those forecasts. What the abundance of data really
shows though, is that the number of variables affecting weather is almost
overwhelming, not just to you, but for meteorologists, too.
Statistical computer models play an important role in making predictions
about major weather-related events, such as hurricanes, earthquakes, and vol-
cano eruptions. Scientists still have some work to do before they can predict
tornados before they begin to form or tell you exactly where and when a hur-
ricane is going to hit land, but that’s certainly their goal, and they continue to
get better at it. For more on modeling and statistics, see Chapter 18.
Musing about movies
Moving on to the arts section, I saw several ads for current movies. Each
movie ad contains quotes from certain movie critics: “Two thumbs up!” “The
supreme adventure of our time,” “Absolutely hilarious,” or “One of the top ten
films of the year!” Do you pay attention to the critics? How do you determine
which movies to go to? Experts say that although the popularity of a movie
may be affected by the critics’ comments (good or bad) in the beginning of a
film’s run, word of mouth is the most important determinant of how well a film
does in the long run.
Studies also show that the more dramatic a movie is, the more popcorn is
sold. Yes, the entertainment business even keeps tabs on how much crunch-
ing you do at the movies. How do they collect all this information, and how
does it impact the types of movies that are made? This, too, is part of statis-
tics: designing and carrying out studies to help pinpoint an audience and find
out what they like, and then using the information to help guide the making
of the product. So the next time someone with a clipboard asks if you have a
minute, you may want to stand up and be counted.
Highlighting horoscopes
Those horoscopes: You read them, but do you believe them? Should you? Can
people predict what will happen more often than just by chance? Statisticians
have a way of finding out, by using something they call a hypothesis test (see
Chapter 14). So far they haven’t found anyone who can read minds, but people
still keep trying!

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