Herding Cats

Quote of the Day

The theory of probability is at the bottom, nothing but common sense reduced to calculus. Pierre de Laplace, Theorie Analytique de Probabilitesy introduction, 1812-20 Read more →

Math for New Year

Thanks, Stephan Vandevoorde, Gent Belgium Read more →

DDSTOP The Saga Continues

There's been a rash of conjectures about all kinds of bad business, project, and software development (agile and traditional) management ideas of late. Time to update the Don't Do Stupid Things on Purpose (DDSTOP) post. “There’s nothing more dangerous than... Read more →

Non-Ergodic Behaviour of Projects

In a previous post Why Johnny Can't Do The Math, the suggestion that estimates are non-ergodic is a Category error. It's the underlying processes that are ergodic or non-ergodic, not the estimates of that process. In this case, the project... Read more →

Quote of the Day

Understanding First Principles is the basis of all understanding - Dr. Kaye Remington, PGCS, Canberra Australia, 14 August 2018 Without first principles, immutable first principles actually, any suggested improvement of anything is just wishful thinking uninformed by any governance, boundary... Read more →

Quote of the Day

But to us, probability is the very guide to life - Bishop Joseph Butler (1756) Read more →

Quote of the Day

“The important question about methods is not ‘how’ but ‘why’” - Tukey Read more →

Why Johnny Can't Do The Math

A previous post, Why Johnny Can't Estimate, mentioned some resources for estimating, the principles of business and technical management that demand estimates be made to make decisions, and background on the sources of uncertainty, that create risk, that require estimating... Read more →

Quote of the Day - Mathematics

By concentrating on what, and leaving out why, mathematics is reduced to an empty shell. The art is not in the “truth” but in the explanation, the argument. It is the argument itself which gives the truth its context, and... Read more →

Modeling the Future is the Basis of Project Success

There's a notion going around that ... “I don’t believe you can make a model of a possible future.” This ignores the principles of predictive analytics, and the direct management actions taken to produce outcomes from those analytical models found... Read more →

Quote of the Day

No sensible decision can be made without taking into account not only the world as it is, but the world as it might be — Isaac Asimov To make sensible decisions, in the presence of uncertainty - reducible and irreducible... Read more →

Don't Be Fooled

This is a new Category on Herding Cats that comes from my finishing of the book Standard Deviations: Flawed Assumptions, Tortured Data, and Other Ways to Lie with Statistics, Gary Smith. Of late I've encountered many people on the web... Read more →

Quote of the Day - Sample Errors

Observational studies are inherently challenging because of the potential for self-selection bias and confounding factors. Always be wary of studies the use the data to discover the theory. - Standardd Deviations: Flawed Assumptions, Tortured Data, and Other Ways to Lie... Read more →

Quote of the Day - Don't Be Fooled

Provocative assertions are provactive precisely because they are counterintuitive - which is a very good reason for skepticism. When you hear such an assertation, don't be easily persuaded that you are wrong. It may well be that the provocative assertation... Read more →

Monte Carlo Simulation

Estimation is part of project management. The most important estimates for the project manager are related to time and cost. And remember you're High School Economics class - The Value of something cannot be determined alone, you need to know... Read more →

Mathematics for Engineering and Software Development

When we encounter engineering problems that are beyond the de minimis category, they usually involve some form of mathematics. Probability, Statistics, Measurements, Calculus and the like. Here's a collection of downloadable books that can be the resources needed to address... Read more →

Cone of Uncertainty - Revisited

We're writing two chapters in an upcoming Project Management Book, with a working title, The Gower Handbook of Project Performance for Agile, Waterfall and Everything in Between, edited by Mark Phillips. One chapter on the Principles of Risk Management and... Read more →

Quote of the Day

I know not why I am so sad - Antonio, at the beginning of The Merchant of Venice Our brains have been designed from evolution to make calculations about possible futures. This is called deciding. When this deciding takes place... Read more →

Quote of the Day

Some mathematicians are birds, others are frogs. Birds fly high in the air and survey broad vistas of mathematics out to the far horizon. They delight in concepts that unify our thinking and bring together diverse problems from different parts... Read more →

Biases in Project Management and How to Remove Them

There is always lots of complaining about the biases introduced into managing projects and making the estimates needed to make project decisions. In Kahnemann's Thinking Fast and Slow there are three biases. † Cognitive bias - a mistake in reasoning,... Read more →