# A Level Statistics

## What is it about at sixth form level?

A fair coin is tossed nine times in a row and lands heads each time. Will it land heads the next time? Many people feel that it is quite unlikely and would bet on tails. That run of luck surely has to end! Yet it is statistically just as likely to land on heads as on tails. Chance, as they say, has no memory. Now suppose that you read that scientists have just discovered that if you eat chocolate regularly, the risk of your skin turning bright orange increases by a factor of 100. That’s enough to worry many people. Indeed, “shock” headlines of this kind can be found across the “science” pages of many national newspapers. By itself, it should not worry anyone. Perhaps the underlying odds of developing orange skin are astronomically small. If so, a hundredfold increase will pose a negligible absolute increase in risk.

When it comes to statistics, our intuitions often lead us astray. In a world where we are bombarded with ever more data, it is increasingly important to have a good understanding of how to interpret patterns and probabilities. The emphasis of the course is on developing a rigorous understanding of how to approach and interpret data. You will learn how to decide which tests are appropriate to determine which kinds of patterns and how to evaluate the results. Although you will have proper grounding in the mathematics, the course is designed to show you how to use statistics across a wide range of real-world situations.

The course is a one-year course, meaning that you will sit the AS and the A2 together in the summer.

Autumn Term

The AS is divided into three modules. In Unit 1, you will look at numerical measures, probability, binomial and normal distributions, estimation, and correlation and regression. In Unit 2, you will look at time series, sampling, discrete probability distributions, interpretation of data and hypothesis testing. In Unit 3, you will look at contingency tables, hypothesis testing and non-parametric methods.

Spring and Summer Terms

The A2 is also divided into three modules. In Units 4 & 5, you will look at continuous probability
distributions, distributional approximations, estimation, and hypothesis testing. In Unit 6, you will look at experimental design, analysis of variance, statistical process control, and acceptance sampling.

## Why study it and what skills does it develop?

A qualification in statistics is valuable if you wish to pursue study in the social sciences and in medicine. It will develop your skills of analysis and abstract thinking. In particular, it will sharpen your sensitivity to patterns and teach you how to overcome misleading intuitions and cognitive biases.

## What prior knowledge and skills are required?

You should have a grade B or above Maths (I)GCSE.

## How is the course assessed?

AS & A level

The course is assessed entirely by examination in May/June. There are papers on each module. Each paper is worth one third of the AS level or one sixth of the A level. Each paper lasts 1 hour 30 minutes.

Statistics 1 (2nd Edition)
By R. Williamson et al

Statistics 2 and 3 (2nd Edition)
By R. Williamson et al

A level Statistics for AQA SS4
By R. Williamson, G. Buque
Available by special order from AQA

A level Statistics for AQA SS5
By R. Williamson, G. Buque
Available by special order from AQA

A level Statistics for AQA SS6
By R. Williamson, G. Buque
Available by special order from AQA

## Exam Board and Specification Codes

AS: Pearson-Edexcel 5381, A2: Pearson-Edexcel 6831

Mike Danzelman