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.
How is a property designated as read-only? In VB.NET: Public Read-Only Property Property Name As Return Type Get? Your Property execution goes in here End Get End Property.
prototype model
Q. Show the Responsibilities of session layer? Session layer: Main functions of this layer are to establish, synchronize and maintain the interaction between two communicatio
Q. Explain about of Unicode? This is a newer International standard for character representation. Unicode offers a unique code for each character irrespective of Program, platf
Define data type and abstract data type comment upon the significant of both
Complete Binary tree A complete binary tree can be described as a binary tree whose non leaf nodes have nonempty left and right sub tree and all leaves are at the similar level
Q. Meaning of every field in MIPS instruction? The meaning of every field in MIPS instruction is given below: op: operation code or opcode rs: First register source
How a Java program compiles? First source file name should be extended with .java extension. For example Myprog.java Execute javac compiler. javac compiler creates
contributes to violence in our society. Others point out that television contributes to the high level of obesity among children. Now, we may have to add financial problems to the
my project is in .net of lan chatting its have tcp\ip connection problem
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