Download The Split-Apply-Combine Strategy for Data Analysis

Journal of Statistical Software
23
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0
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Figure 16: Star glyphs showing deseasonalized trends. Each star shows six years of data,
with seasonal trend removed. This plot contains a lot of data—over 40,000 observations—
and rewards detailed study. Looking at a printed version also helps as the resolution of a
printer (600 dpi) is much higher than that of the screen (∼100 dpi). Interesting features
include the higher variability in the North, locations in the mountains of South America with
a large difference between starting and ending temperatures, and an unusual month common
to many of the locations in the Pacific.
R> coefs_df <- melt(coefs)
R> head(coefs_df)
lat long month value
1 -21.2 -114
Jan
264