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A
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government organization in the United States.
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A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Schematic comparing global versus local metrics. Schematic comparing global versus local metrics. (a) global point of view leading to summary statistics, illustrated by bar graph, (b) local or individual-cell point of view leading to histograms, illustrated by frequency plot.
