Log Scales
ROW/COL B C D E F G H I
4 Frequently data is hard to understand without using logs
5 Here is some Forecasted data for the next few years. Look at the graphs below
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8 Year Forecast
log of number
Alternative way to express the # =LOG(C9)
9 2000 10 1 10 ^1
10 2001 100 2 10 ^2
11 2002 1,000 3 10 ^3
12 2003 10,000 4 10 ^4
13 2004 100,000 5 10 ^5
14 2005 1,000,000 6 10 ^6
15 2006 10,000,000 7 10 ^7
16 2007 100,000,000 8 10 ^8
17 2008 1,000,000,000 9 10 ^9
18 2009 10,000,000,000 10 10 ^10
19 2010 100,000,000,000 11 10 ^11
20 2011 1,000,000,000,000 12 10 ^12
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24 Here is one picture of the data
25 Notice that it is hard to see what is going on.
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55 Here is a picture using the log scale
56 Notice that you can see the series is going straight up.
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88 Using the logs of the data rather than a log axis
89 You see the same effects
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