2.2.2 Computational methods A Level OCR Computer Science

What are computational methods

They are problem-solving techniques that use algorithms and mathematics to analyse and solve complex problems using a computer.

What is divide-and-conquer

A method of solving complex tasks by continually breaking them down into smaller, simpler sub-problems that can all be solved directly. The solutions to each sub-problem is recursively combined to create the solution to the larger problem.

Which common algorithms use divide-and-conquer

Binary search, merge sort, quick sort

What are the advantages and disadvantages of using divide-and-conquer

These algorithms are typically very time efficient and can solve problems quickly if concurrent or parallel processing is available. This technique also promotes reusing of program modules. However, these algorithms take up a lot of space in memory when running.

What is backtracking

A problem-solving technique that incrementally builds partial solutions to problems, abandoning them if they fail and returning to the last potentially successful decision point to explore other potential solutions.

Which common algorithms use backtracking

Depth-first graph traversals, pathfinding algorithms

What are the advantages and disadvantages of backtracking

This technique is almost guaranteed to find a solution if one exists since every possible path is checked. However, it is very time and memory intensive (high time and space complexity).

What is data mining

The process of using statistical analysis and machine learning to identify and find hidden patterns, correlations and anomalies in large datasets that would not be immediately obvious to a human.

Why is data mining useful

It can be used to inform decision-making by predicting future trends based on past behaviour. This helps to optimise user experience and maximise profits.

What is heuristics

A problem-solving technique that makes use of experience, such as rules of thumb or educated guesses, to find an approximate solution to a complex problem quickly rather than a perfect solution that would take too much time.

How does the A* pathfinding algorithm use heuristics

It combines the actual distance travelled from the start node (as calculated by Djikstra’s algorithm) with a heuristic of the estimated remaining distance to the end node, allowing it to find the best path without checking every node.

What is performance modelling

An approach to simulating the behaviour of an algorithm or system before it is implemented by testing it on lower demand than it will run on and using mathematical approximations to determine how processing demands will scale.