Normal Distribution Explained: Properties, Z-Scores and Real-World Examples

Statistics

Z-scores and the normal table look intimidating the first time and become completely mechanical by the tenth. The Statistics Made Simple Practice Questions workbook has a full chapter of normal distribution problems to get you there. Statistics · Probability...

Linear Programming in Economics and Business: Graphical Method, Constraints and Simplex Method

Mathematical Economics, Microeconomics

Linear Programming in Economics and Business: The Graphical Method, Shadow Prices and SimplexIn 1947 George Dantzig solved a problem the US Air Force had considered computationally hopeless. His method now quietly routes your parcels, schedules airline crews, blends...

Descriptive Statistics in Economics: Mean, Variance, Skewness, and How Data Misleads

Statistics

Descriptive Statistics in Economics Before you do any fancy analysis — first, just look at your data! Why bother with descriptive stats? Imagine you’re a doctor. Before you diagnose someone, you take their temperature, check their pulse, look at their weight....

What is Standard Deviation? Formula, Calculation and Examples

Statistics

Standard deviation is the single most-used spread statistic in the whole subject, and dividing by n instead of n−1 is the single most common mistake made calculating it. The Statistics Made Simple Practice Questions workbook has a full chapter of drills built...

Derivatives in Economics: Marginal Cost, Revenue and Profit with Step-by-Step Calculus Examples

Mathematical Economics, Microeconomics

Derivatives in Economics: Marginal Cost, Marginal Revenue and Profit MaximisationHere is the secret that makes the second year of economics much easier than the first: every time a textbook says “marginal”, it means “derivative”. Marginal cost...

Mean, Median and Mode: Definitions, Differences and Examples

Statistics

Picking the wrong measure of central tendency doesn’t just cost exam marks — it’s how misleading headlines about “average” income or house prices get made. The Statistics Made Simple Practice Questions workbook has a full section of...

Type I vs Type II Errors: A Way to Never Confuse Them Again

Statistics

This is a topic where recognition beats memorisation — you need to have seen enough scenarios to classify a new one instantly. The Statistics Made Simple Practice Questions workbook drills exactly that, with exam-style questions and full mark schemes.Statistics...

What a P-Value Actually Means (And the Three Things It Doesn’t)

Statistics

If p-values still feel slippery after this, the cure is repetition on real numbers. The Statistics Made Simple Practice Questions workbook has over a hundred questions on hypothesis testing alone, each with a fully worked answer.Statistics · InferenceWhat a...

Standard Deviation vs Standard Error: What’s the Difference?

Statistics

If you have ever divided by √n when you should not have — or forgotten to when you should — you are in very large company. The Statistics Made Simple Practice Questions workbook has a full chapter of drills built around exactly this...

Net Present Value (NPV) and Present Value in Economics: Formula, Examples and Investment Decisions

Financial Economics, Mathematical Economics, Microeconomics, Public Economics

Net Present Value: Discounting, Investment Appraisal and the Rate That Decides EverythingA pound today is worth more than a pound next year. Everyone nods at that. Almost nobody appreciates that the exact size of “more” — a single number chosen before any...