Pruning and sorting, Computer Engineering

Assignment Help:

Pruning and Sorting:

This means we can test where each hypothesis explains as entails a common example that we can associate to a hypothesis a set of positive elements in which it explains and a similar set of negative elements. Moreover there is also a similar analogy with general and specific hypotheses as described above as: whether a hypothesis G is more practical than hypothesis S so then the examples explained by S will be a subset of those explained by G.

In fact we will assume the following generic search strategy for an ILP system as: (i) is a set of current hypotheses is maintained and QH (ii) is at each step in the search, a hypothesis H is taken from QH and some inference rules applied to it in order to generate some new hypotheses that are then added to the set as we say that H has been expanded (iii) is, this continues until a termination criteria is met.
However this leaves many questions unanswered. By looking first at the question of that hypothesis to expand at a particular stage, ILP systems associate a label with each hypothesis generated that expresses a probability of the hypothesis holding which is given the background knowledge and examples are true. After then there hypotheses with a higher probability are expanded rather than those with a lower probability and hypotheses with zero probability are pruned from the set QH entirely. However this probability calculation is derived using Bayesian mathematics and we do not go into the derivation here. Moreover we hint at two aspects of the calculation in the paragraphs below.

In just specific to general ILP systems there the inference rules are inductive so each operator takes a hypothesis and generalizes it. However as mentioned above that this means like the hypothesis generated will explain more examples than the original hypothesis. In fact as the search gradually makes hypotheses more generally there will come a stage where a newly formed hypothesis H is common enough to explain a negative example as e- . Thus this should therefore score zero for the probability calculation is just because it cannot possibly hold given the background and examples being true. This means the operators only generalize so there is no way through H can be fixed to not explain e-, so pruning it from QH means the zero probability score is a good decision.


Related Discussions:- Pruning and sorting

Define hypertext verses hypermedia briefly, Define Hypertext verses Hyperme...

Define Hypertext verses Hypermedia briefly. Hypertext is fundamentally the same as regular text- this can be stored, read, searched or edited along with a significant exception

Explain user datagram protocol, Explain User Datagram Protocol. UDP(Use...

Explain User Datagram Protocol. UDP(User Datagram Protocol) : User Datagram Protocol uses a connectionless communication paradigm. It is an application using UDP does not re

Define functions with that virtual memory can be implemented, Virtual memor...

Virtual memory can be implemented with ? With Segmentation and Paging Virtual memory can be implemented.

Show the Features of parallel virtual machine, Q. Show the Features of para...

Q. Show the Features of parallel virtual machine? Easy to install; Easy to configure; Multiple users each can use PVM concurrently; Multiple applications fro

Keyboard status word generator, Q.  Write short note on Interfacing Keyboar...

Q.  Write short note on Interfacing Keyboard, giving block diagram. Why do we need to introduce circuitry called Keyboard Status Word Generator?

Enumerate in detail about image scanners, Enumerate in detail about Image S...

Enumerate in detail about Image Scanners Drawings, graphs, colour and black-and-white photos, or text can be stored for computer processing with an image scanner by passing an

Process of breadth first search, Process of Breadth first search: It's...

Process of Breadth first search: It's very useful to think of this search as the evolution of the given tree, and how each string of letters of word is found via the search in

Determine the current allocation state and granted process, An operating sy...

An operating system contains 3 resource classes. The number of resource units in these classes is 7, 7 and 10. The current resource allocation state is shown below:

Define the edge-triggered flip-flops, Define the Edge-Triggered Flip-flops?...

Define the Edge-Triggered Flip-flops? An edge-triggered flip-flop changes states either at the negative edge (falling edge) or at the positive edge (rising edge) of the clock p

What are the basic components of an expert system, Q. What are the basic co...

Q. What are the basic components of an expert system? ANSWER: There are three components of components: Information, people, and IT components. Information kinds are domain exp

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd