2.2.2 Computational Methods

Question 1

What is backtracking?

Answer 1

An algorithm that incrementally finds a solution by methodically trying different sequences and abandoning a path when it knows it cannot lead to a valid solution.

Question 2

What are computable problems?

Answer 2

A problem for which every instance can be solved in a finite number of steps by means of an algorithm

Question 3

What are computational methods?

Answer 3

A method of solving a problem which involves some form of computation in devising and implementing an algorithm

Question 4

What is divide and conquer?

Answer 4

An algorithm design technique to decompose and solve problems by reducing the problem size with each iteration until the subproblem becomes solvable

Question 5

What are heuristics?

Answer 5

A rule-of-thumb algorithm which can produce a valid suboptimal solution for a hard/intractable problem as an approximation

Question 6

What is performance modeling?

Answer 6

The process of simulating the behaviour of a model under different virtual user and system loads by mathematical approximation

Question 7

What is pipelining?

Answer 7

The process of splitting a task into parts and then searching for subtasks that can be processed simultiesly to overlap the processing of each part

Question 8

What is problem recognition?

Answer 8

The ability to recognise the most effective strategy to solve a problem.

Question 9

What is visualisation?

Answer 9

The use of a visual representation of an algorithm or data structure to translate a problem and its solution to a more human-readable form.

Question 10

What makes a problem computable?

Answer 10

Finite
Realistic amount of time
Consists of inputs/outputs and calculations

Question 11

What makes a problem intractable?

Answer 11

It may be ​impractical to solve them due to the amount of resources​ or length of time​ they require in order to be completed.

Question 12

What constraints are there for which problems can be solved computationally?

Answer 12

The number of problems that can be solved computationally are constrained by factors such as processing power​, ​speed, and memory.

Question 13

Advantages of decompisiton?

Answer 13

Makes the project easier to manage​, as different software development teams can be assigned dif sections of the code according to their specialisms.
Sections can be ​ individually designed, developed and tested​ before being combined Enables multiple parts of the project to be developed in parallel​ (faster)
Makes debugging simpler and less time-consuming, as it is easier to identify, locate and fix errors​ in individual modules.

Question 14

What is decrease and conquer?

Answer 14

The principle of divide and conquer is also used in problems which can be reduced by less than half in every iteration.

Question 15

What is the benefit of divide and conquer algorithms?

Answer 15

The size of the problem is halved with each iteration, which greatly​ simplifies very complex problems​.
Meaning that as the size of a problem grows, the time taken to solve it will not grow as significantly.

Question 16

What is the time complexity of divide and conquer algorithms?

Answer 16

O(logn)

Question 17

What is a disadvantage of divide and conquer algorithm?

Answer 17

Divide and conquer mostly makes use of recursion; it faces the same problems that all recursive functions face
Stack overflow​ will cause the program to crash, and large programs are very​ difficult to trace​.

Question 18

What is data mining?

Answer 18

A technique used to identify patterns or outliers in​ large sets of data​, termed big data​. Big data is typically collected from a variety of sources​.

Question 19

What is data mining used for?

Answer 19

Data mining is used in software designed to spot trends or identify correlations​ between data which are​ not immediately obvious.
Insights from data mining can be used to make predictions about the future based on previous trends​.
Making it a useful tool in ​ assisting business and marketing decisions

Question 20

How does data mining relate to legal issues?

Answer 20

Data mining often involves the​ handling of personal data; it is crucial that it is dealt with in accordance with the present legislation regarding data protection.
As of 2018, all data held and processed by organisations within the EU must follow the rules set by the ​GDPR.

Question 21

What is performance modelling used for?

Answer 21

This is useful for safety-critical computer systems, where it is not safe to do a real trial run before the system can be implemented.

Question 22

What can the results of performance modeling be used for?

Answer 22

The results of performance modelling can help companies judge the capabilities of a system​, how it will cope in different environments, and assess whether it is safe to implement​.