IEVref:171-07-18ID:
Language:enStatus: Standard
Term: redundancy, <in information theory>
Synonym1:
Synonym2:
Synonym3:
Symbol: R
Definition: amount by which the decision content H0 exceeds the entropy H

R = H0 − H

EXAMPLE Let { a,b,c } MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaiGc9aspC0FXdbbc9asFfpec8Eeeu0lXdbb a9frFj0xb9Lqpepeea0xd9s8qiYRWxGi6xij=hbba9q8aq0=yq=He9 q8qiLsFr0=vr0=vr0db8meaabaGacmaadiWaaiWabaabaiaafaaake aaomaacmaakeaajugibiaadggacaGGSaGaamOyaiaacYcacaWGJbaa kiaawUhacaGL9baaaaa@43FE@ be a set of three events and let p(a)=0,5 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaiGc9aspC0FXdbbc9asFfpec8Eeeu0lXdbb a9frFj0xb9Lqpepeea0xd9s8qiYRWxGi6xij=hbba9q8aq0=yq=He9 q8qiLsFr0=vr0=vr0db8meaabaGacmaadiWaaiWabaabaiaafaaake aacaWGWbGaaiikaiaadggacaGGPaqcLbqacqGH9aqpcaaIWaGaaiil aiaaiwdaaaa@43D9@ , p(b)=0,25 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaiGc9aspC0FXdbbc9asFfpec8Eeeu0lXdbb a9frFj0xb9Lqpepeea0xd9s8qiYRWxGi6xij=hbba9q8aq0=yq=He9 q8qiLsFr0=vr0=vr0db8meaabaGacmaadiWaaiWabaabaiaafaaake aacaWGWbGaaiikaiaadkgacaGGPaqcLbqacqGH9aqpcaaIWaGaaiil aiaaikdacaaI1aaaaa@4496@ and p(c)=0,25 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaiGc9aspC0FXdbbc9asFfpec8Eeeu0lXdbb a9frFj0xb9Lqpepeea0xd9s8qiYRWxGi6xij=hbba9q8aq0=yq=He9 q8qiLsFr0=vr0=vr0db8meaabaGacmaadiWaaiWabaabaiaafaaake aacaWGWbGaaiikaiaadogacaGGPaqcLbqacqGH9aqpcaaIWaGaaiil aiaaikdacaaI1aaaaa@4497@ be the probabilities of their occurrences. The redundancy of this set is: R=1,585 Sh1,50 Sh =0,085 ShMathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaiGc9aspC0FXdbbc9asFfpec8Eeeu0lXdbb a9frFj0xb9Lqpepeea0xd9s8qiYRWxGi6xij=hbba9q8aq0=yq=He9 q8qiLsFr0=vr0=vr0db8meaabaGacmaadiWaaiWabaabaiaafaaake aaqaaaaaaaaaWdbiaadkfacqGH9aqpcaaIXaGaaiilaiaaiwdacaaI 4aGaaeiiaiaabofacaqGObGaeyOeI0IaaGymaiaacYcacaaI1aGaaG imaiaabccacaqGtbGaaeiAaiaabccacqGH9aqpcaaIWaGaaiilaiaa icdacaaI4aGaaeiiaiaabofacaqGObaaaa@517B@ .

Note 1 to entry: Usually, messages can be represented with fewer characters by using suitable codes; the redundancy can be considered as a measure of the decrease of the average length of the messages accomplished by appropriate coding.


Publication date:2019-03-29
SourceIEC 80000-13:2008, 13-28, modified – Addition of information useful for the context of the IEV, and adaptation to the IEV rules
Replaces:
Internal notes:
CO remarks:
TC/SC remarks:
VT remarks:
Domain1:
Domain2:
Domain3:
Domain4:
Domain5: