Evidence Hierarchy

Stats Training Materials – Statistical Inference & Hypothesis Testing

March 8, 2019 By Nigel Marriott

Mention P-values and most people will probably shudder at some memory of an incomprehensible lecture or lesson on statistical tests. Words like null hypotheses, t-tests, statistical significance might pop into your mind with little understanding of what they are about. What you may know is that scientists have to report a p-value for any experiment they do or do they?

The area of Statistical Inference is a core area of study for any statistician. Put simply, Inference means to infer from the observations you’ve made about your data and to draw conclusions about what might be happening in real life. There are two parts to Inference.

Stats Training Materials – Basic Statistical Concepts

February 1, 2019 By Nigel Marriott

A sound grasp of basic statistical concepts is essential to have any hope of acquiring the mindset of a statistical thinker and to be able to use statistical methods. My introductory course “The 6 Concepts of Statistical Thinking” lays the foundations in the following.

Probability – the difference between conditional & absolute probability.
Risk – why it is an extension of probability and the importance of alpha (false positive) and beta (false negative) risk.
Expectation – how to summarise a dataset into one number which measures its location.
Variance – how to measure the spread of a dataset.
Distribution – how to describe the shape of a dataset.
Correlation – how to measure the relationship between two variables and understand the two golden rules of correlation.

Stats in the News #2 – Who reads fake news?

April 15, 2017 By Nigel Marriott

Fake news has entered the political dictionary over the last year. Suddenly, politicians and commentators are worried that elections are being influenced by false stories being circulated that appear to be genuine. Social media platforms are under pressure to filter out such stories raising the old questions of censorship and “who guards the guards?” However, evidence on the extent and influence of fake news is thin on the ground.

A recent article from the BBC website “The rise of left wing, anti-Trump fake news” has provided some firmer evidence which I think makes a good case study for my evidence hierarchy or circle.

Stats in the News #1 – Science & Technology March 2017

March 25, 2017 By Nigel Marriott

Welcome to my first post where I put my Evidence Hierarchy or Circle into practice and show you what is behind the headline.

Today I am concentrating on science and technology related articles from the BBC website since that is accessible to nearly everyone. As always, I am critiquing the article more than the research since I have not read the research papers that motivated the article. The 3 articles are:

“Fruit shaped sensor can improve freshness“.
“Robots to affect up to 30% of jobs“
“Dinosaurs may have UK origin“

[Read more…] about Stats in the News #1 – Science & Technology March 2017

Stats in the News #0 – The Evidence Hierarchy and how to use it

March 25, 2017 By Nigel Marriott

“Graduates aren’t skilled enough!” says a BBC headline. What is your immediate reaction? If you decide to find out more and read the article, you will see the following.

A brief reference to a survey of a 174 organisations, half of whom are apparently moaning graduate skills.
3 brief interviews with recent graduates asking what they wish they had learned before starting their job.

After reading this, do you feel that a case has been made that universities are slipping up? How much weight should you place on this article and the information it contains? One of the major problems with news these days is that we are bombarded with articles about so many things that it can difficult to sort the good from the bad, especially when articles are referring to data in one way or another. My Evidence Hierarchy provides a short cut to assess the usefulness of news articles and with a bit of practice, I hope the result will be less stress for you about what is going on in the world.