International Journal of Scientific & Engineering Research, Volume 3, Issue 4, April-2012 1
ISSN 2229-5518
Jha P., MishraVikas Kumar
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1. Introduction: Uncertainty and fuzziness are the basic nature of human thinking and of many real world objectives. Fuzziness is found in our decision, in our language and in the way we process information. The main use of information is to remove uncertainty and fuzziness. In fact, we measure information supplied by the amount of probabilistic uncertainty removed in an experiment and the measure of uncertainty removed is also called as a measure of information while measure of fuzziness is the measure of vagueness and ambiguity of uncertainties. Shannon [2] used “entropy” to measure uncertain degree of the randomness in a probability distribution. Let X is a discrete random variable with probability distribution in an experiment. The information contained in this experiment is given by
Which is well known Shannon entropy.
The concept of entropy has been widely used in
different areas, e.g. communication theory, statistical mechanics, finance, pattern recognition, and neural network etc. Fuzzy set theory developed by Lofti A. Zadeh [8] has found wide applications in many areas of science and technology, e.g. clustering, image processing, decision making etc. because of its capability to model non-statistical imprecision or vague
It may be recalled that a fuzzy subset A in U (universe of discourse) is characterized by a membership function which represents the grade of membership of as follows
In fact associates with each a grade of membership in the set A. When is valued in it is the characteristic function of a crisp (i.e. nonfuzzy) set. Since and gives the same degree of fuzziness, therefore, corresponding to the entropy due to Shannon [2], De Luca and Termini [1] suggested the following measure of fuzzy entropy:
De Luca and Termini introduced a set of properties and these properties are widely accepted as a criterion for defining any new fuzzy entropy. In fuzzy set theory, the entropy is a measure of fuzziness which expresses the amount of average ambiguity/difficulty in making a decision whether an element
belongs to a set or not. So, a measure of average fuzziness in a fuzzy set should have at least the
i) when
ii) increases as increases from
0 to 0.5.
0.5 to 1.
iv) i.e. v) is a concave function of
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International Journal of Scientific & Engineering Research, Volume 3, Issue 4, April-2012 2
ISSN 2229-5518
Kullback and Leibler [7] obtained the measure of
directed divergence of probability distribution from the probability
distribution as
Let A and B be two standard fuzzy sets with same supporting points and with fuzzy
vectors and
. The simplest measure of fuzzy directed divergence as suggested by Bhandari and Pal (1993), is
satisfying the conditions:
i)
ii)
iii)
iv) is a convex function of
later kapur [5],[6] introduced a number of trigonometric hyperbolic and exponential measures of fuzzy entropy and fuzzy directed divergence. In section 2 and 3 we introduce some new trigonometric, hyperbolic and exponential measures of fuzzy entropy and measures of fuzzy directed divergence.
Consider the function where is a convex function which gives us
is a new measure of fuzzy entropy. in particular for
is also a new measure of fuzzy entropy.
is a special case of when .
Another special case of arises when we get
Another trigonometric measure of fuzzy entropy is
reduces to when reduces to when .
reduces to when
is a 2-parameter measure of fuzzy entropy. If we put we get
is a new measure of fuzzy entropy. Clearly above given measures of fuzzy entropy are satisfying all the properties which are given in section 1. So these are valid measures of fuzzy entropy.
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International Journal of Scientific & Engineering Research, Volume 3, Issue 4, April-2012 3
ISSN 2229-5518
where are all convex functions and gives us following valid measures of fuzzy entropy
Since are also convex functions for , we get the following additional
measures of fuzzy entropy.
Since is a convex function when we get the measure of fuzzy entropy
Using the convexity of we get the following measures of hyperbolic fuzzy
directed divergence.
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International Journal of Scientific & Engineering Research, Volume 3, Issue 4, April-2012 4
ISSN 2229-5518
Again since are also
convex functions for , we get the following more general hyperbolic measures of fuzzy directed
divergence.
Special case for m=0 and m=1 are
(21)
In section 2 and 3 by using the convexity of some trigonometric, hyperbolic and exponential function and satisfying the conditions of fuzzy entropy and fuzzy directed divergence we get some new trigonometric, hyperbolic and exponential measures of fuzzy entropy
and fuzzy directed divergence.
Since is a convex function when we get the following measures of fuzzy directed divergence
IJSER © 2012
International Journal of Scientific & Engineering Research, Volume 3, Issue 4, April-2012 5
ISSN 2229-5518
Jha P. Department of Mathematics,Govt Chattisgarh P.G. College, Raipur, Chattisgarh(India)
MishraVikas Kumar Department of Mathematics, Rungta College of Engineering and Technology, Raipur, Chattisgarh(India)
[1] A. De Luca and S. Termini, A Definition of a Non-probabilistic Entropy in the Setting of fuzzy sets theory, Information and Control, 20, 301-312, 1972.
[2] C.E.Shannon (1948). “A Mathematical Theory of
Communication”. Bell. System Tech. Journal Vol. 27, pp. 379-
423,623-659.
[3] D. Bhandari and N. R. Pal, Some new information measures for fuzzy sets, Information Science, 67, 204 - 228, 1993.
[4] F.M.Reza (1948&1949). “An introduction to information theory”. Mc. Graw-Hill, New-York.
[5] J.N.Kapur. Some New Measures of Directed Divergence. Willey Eastern Limited.
[6] J.N.Kapur.Trigonometrical Hyperbolic and Exponential
Measure of Fuzzy Entropy and Fuzzy Directed Divergence. MSTS
[7] S. Kullback and R.A. Leibler, On Information and Sufficiency, Annals of Mathematical Statistics,
22,79 - 86, 1951.
[8] L. A. Zadeh, Fuzzy Sets, Information and Control, 8, 338 - 353,
1965.
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