Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Arbitrary categorisation - learning decision trees:
Through visualising a set of boxes with some balls in. There if all the balls were in a single box so this would be nicely ordered but it would be extremely easy to find a particular ball. Moreover If the balls were distributed amongst the boxes then this would not be so nicely ordered but it might take rather a whereas to find a particular ball. It means if we were going to define a measure based at this notion of purity then we would want to be able to calculate a value for each box based on the number of balls in it so then take the sum of these as the overall measure. Thus we would want to reward two situations: nearly empty boxes as very neat and boxes just with nearly all the balls in as also very neat. However this is the basis for the general entropy measure that is defined follows like:
Now next here instantly an arbitrary categorisation like C into categories c1, ..., cn and a set of examples, S, for that the proportion of examples in ci is pi, then the entropy of S is as:
Here measure satisfies our criteria that is of the -p*log2(p) construction: where p gets close to zero that is the category has only a few examples in it so then the log(p) becomes a big negative number and the p part dominates the calculation then the entropy works out to be nearly zero. However make it sure that entropy calculates the disorder in the data in this low score is good and as it reflects our desire to reward categories with few examples in. Such of similarly if p gets close to 1 then that's the category has most of the examples in so then the log(p) part gets very close to zero but it is this that dominates the calculation thus the overall value gets close to zero. Thus we see that both where the category is nearly - or completely - empty and when the category nearly contains as - or completely contains as - all the examples and the score for the category gets close to zero that models what we wanted it to. But note that 0*ln(0) is taken to be zero by convention them.
Explain Auto increment and Auto decrement mode The register is incremented or decremented after (or before) its value is used to access memory. The address stored in the regi
Explain in brief about the broadband It isn't just computers which can be linked without wires, different peripheral devices can be linked to a computer system without the need
HOW TO CONVERT THE NUMBER INTO ALPHABET USING C/C++ PROGRAM
What is Debate Debate took place in the 1980s and first half of the 1990s. It was resolved as RISC the winner since it allows more efficient pipelining, results in simpler hard
Illustrate how 74147 series TTL can be used as a decimal-to-BCD encoder. Ans. Available IC in 74 series is 74147 that is a priority encoder. Such IC has active low inp
Explain about MMX architecture MMX architecture introduces new packed data types. Data types are eight packed, consecutive 8-bit bytes; four packed, consecutive 16-bit words;
What is multiprogramming or multitasking? The operating system manages the concurrent implementation of several application programs to make the best possible uses of computer
Q. What is Small Computer Systems Interface? The other well-liked way is to connect a disk drive to a PC by a SCSI interface. Common drive choice for high-end workstations or s
i need help
-8 is equal to which signed binary number ? Ans. 10001000 is the signed binary number that equal to - 8. To show negative numbers in the binary system, Digit 1 is utilized fo
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd