Advantages
The advantage of a variable-length code is that unlikely source symbols can be assigned longer codewords and likely source symbols can be assigned shorter codewords, thus giving a low expected codeword length. For the above example, if the probabilities of (a, b, c, d) were, the expected number of bits used to represent a source symbol using the code above would be:
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As the entropy of this source is 1.7500 bits per symbol, this code compresses the source as much as possible so that the source can be recovered with zero error.
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Famous quotes containing the word advantages:
“... is it not clear that to give to such women as desire it and can devote themselves to literary and scientific pursuits all the advantages enjoyed by men of the same class will lessen essentially the number of thoughtless, idle, vain and frivolous women and thus secure the [sic] society the services of those who now hang as dead weight?”
—Sarah M. Grimke (1792–1873)
“In 1845 he built himself a small framed house on the shores of Walden Pond, and lived there two years alone, a life of labor and study. This action was quite native and fit for him. No one who knew him would tax him with affectation. He was more unlike his neighbors in his thought than in his action. As soon as he had exhausted himself that advantages of his solitude, he abandoned it.”
—Ralph Waldo Emerson (1803–1882)
“Can you conceive what it is to native-born American women citizens, accustomed to the advantages of our schools, our churches and the mingling of our social life, to ask over and over again for so simple a thing as that “we, the people,” should mean women as well as men; that our Constitution should mean exactly what it says?”
—Mary F. Eastman, U.S. suffragist. As quoted in History of Woman Suffrage, vol. 4 ch. 5, by Susan B. Anthony and Ida Husted Harper (1902)