Statistics for the Terrified: Glossary

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z 

Click on an item below to see the definition

---

Data:

Information (usually numeric) collected on the participants in a study and on which data analysis is performed.

Data types:

All data is not the same, and different types of data must be handled in different ways.
See also Binary data, Categorical data, Continuous data, Count, Discrete data, Ordinal data.

Decision rule:

A clear statement made at the outset of a study detailing how a decidion on significance is to be made.

Degrees of freedom:

This crops up everywhere in statistical tests, and is used to calculate the p value. It is a fairly deep mathematical topic and we need not go fully into it here. Broadly speaking, the larger the sample size, the larger the df: the smaller the sample, the smaller the df. However, this is modified by the number of groups you have and the parameters being estimated. A small df makes it more difficult to detect significance.

Dependent variable:

The term used for the outcome variable in regression analysis. A variable that depends on another variable is called the dependent variable: the variable on which it depends is called the predictor variable (sometimes the independent variable).
See also Linefitting.

Descriptive statistics:

Simple summary description of data carried out before a full analysis, eg. Mean, Standard error, etc.

Discrete data:

Data that can only take a small set of particular values, usually whole numbers. For instance, you cannot actually have 2.4 children.
See also Data types.

Distribution:

A graph plotting probability against values. There are some typical shapes: normal, uniform, exponential. The normal distribution (bell-shaped) is the most common.
See also Normal distribution, population distribution, null distribution.

Double blind:

When neither subject nor evaluator knows what treatment or regime has been administered. This double-blind approach reduces the risk of bias (psychological or otherwise) being introduced by either the investigator or the subjects of the study. Single-blind occurs when one of these two is aware of the treatment or regime administered. See also Bias, Blinded evaluation, Blind study, Single blind.

---

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z 

"Being a senior academic teaching research to undergraduate and post graduate health care students, the inevitable ogre of statistics appears early in the students experience of my courses. There are few, if any, ways that I have discovered that have my students running for their statistics books with enthusiasm and glee. Needless to say the common fear of numbers and the often complex explanations offered to underpin basic statistical understanding tend to elicit an, at best, lukewarm response and at worst, total denial. However, I have been using Statistics for the Terrified now for the last few years and for those students that use it it has been a transformation. The interactive nature, plenty of visual examples and clear and straightforward explanations of the basic concepts behind probability, data distributions, measures of central tendency and spread and common statistical tests means, first that they don't have to listen to me droning on, second the independent nature of the experience increases both life long and deeper learning and lastly provides me with an initial direction in which to send them when they ask the more simple questions.

"So........they get to be less bored of me, they learn in a deeper and more individual way and I don't have to spend lots of time reiterating the basics to hundreds of students"

David Newell
Research Director, AECC

Learn more...

Free resources:

•   Statistics glossary

•   What is risk?

•   Conditional probability

•   Median and mean

•   Evening the odds

•   The prosecutor's fallacy

•   Clinical trials

•   n - sample size

Statistics for the Terrified:

•   Download demo

•   Buy a copy

•   What is it?

•   What does it cover?

•   Who is it for?

•   What our users say

•   History of S4T

•   User survey results

Contact us:

•   Contact details

  home   |    statistics for the terrified   |    download a demo   |    buy now (UK & EU)   |    buy now (US & Worldwide)   |    free resources   |    contact us   |    sitemap   |    FAQ