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

C++, explain parallel database system

explain parallel database system

8086 microprocessor, In SDK – 86 kit 128KB SRAM and 64KB EPROM is provided ...

In SDK – 86 kit 128KB SRAM and 64KB EPROM is provided on system and provision for expansion of another 128KB SRAM is given. The on system SRAM address starts from 00000H and that

Produce a sequence diagram for the task add, This assignment is based on th...

This assignment is based on the 'Swansea Docklands Heritage Society' case study attached.  The assignment is the third of three related submissions, all based on the Swansea Dockla

How is transaction processing system affected, How is Transaction Processin...

How is Transaction Processing System affect performance of e-commerce sites? Transaction Processing System influences performance of e-commerce sites: Transaction-Processing

Way to interconnect multiple computer across short distance, A computer com...

A computer communication technology that gives a way to interconnect multiple computer across short distance is LAN

What are the registers generally contained in the processor, What are the r...

What are the registers generally contained in the processor? MAR-memory address register MDR-memory data register IR-Instruction Register RO-Rn-General purpose registe

What are the characteristics of dram, What are the characteristics of DRAM?...

What are the characteristics of DRAM? Low cost High density Refresh circuitry is needed

Define thread cancellation and target thread, Define thread cancellation & ...

Define thread cancellation & target thread.  The thread cancellation is the task of terminating a thread before it has done. A thread that is to be cancelled is often referred

Show the classification of printers, Q. Show the Classification of Printers...

Q. Show the Classification of Printers? Printers can be classified on following bases: a) Impact: Impact printers print by impact of hammers on ribbon (for example Dot-Matri

Show the decimal representation in computers, Binary number system is most ...

Binary number system is most common for computer due to two stable states of its components. However unfortunately this isn't a very natural system for us as we deal with decimal n

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