Estimates

# 3 Examples of a Fudge Factor

, updated on
A fudge factor is a number based on observed results as opposed to solid theory, logic or calculations. They are commonly used as a practical measure to overcome uncertainty or complexity. The following are examples.

## Physics

Einstein included an invented "cosmological constant" in his general theory of relativity because his results indicated that the universe was expanding or contracting. This didn't seem right to him, so he included the constant to cancel this out. He later referred to this as "the biggest blunder of my life" as it is now accepted that the universe is indeed expanding.
It is a common practice in science to include fudge factors that derive from measured observations that aren't necessarily explainable with theory and calculation.

## Engineering

Fudge factors may be used in engineering calculations to mitigate risks. These are typically given more formal names as "fudge factor" is commonly interpreted to have negative connotations. For example, an engineer may make a tire 4x stronger than required by anticipated road conditions. The choice of the constant 4 may be somewhat arbitrary.

## Project Management

A project manager may apply a margin of safety into estimates. This may be done using a fudge factor such as multiplying estimates supplied by subject matter experts by 1.5.
 Overview: Fudge Factor Type Definition (1) A number that fits observations but not theory. Definition (2) An ad-hoc number that is invented for practical reasons such as mitigating risk. Notes In science, a fudge factor is typically used openly to represent observations that don't fit a theory.In engineering, a fudge factor may be given a technical name that makes it sound less ad-hoc.In project management, a fudge factor may be an unwritten rule within an organization that isn't officially acknowledged. Related Concepts

## Estimates

This is the complete list of articles we have written about estimates.
Change Analysis
Estimates
Fudge Factor
Project Analysis
Schedule Risk
Scope Risk
Story Points
Work Complexity

## Estimates

Projections of costs, task completion times and resource needs for a project.

## Full-Time Equivalent

An overview of full-time equivalent, commonly known as FTE.

## Story Points

An overview of estimating with story points including planning poker.

An overview of big bang adoption.

## Estimate To Complete

An overview of Estimate to Complete, a common project metric.

## Project Constraint

A list of common project constraints.

## Terms Of Reference vs Project Charter

The difference between a terms of reference and a project charter.

## Common Project Risks

A list of common project risks.

## Lessons Learned Examples

An overview of lessons learned with examples.

## Work Complexity

A list of things that influence work complexity.

## Project Change

The common types of change to a project.

## Project Support

An overview of project support with examples.

## Schedule Risk

An overview of schedule risk with examples.

## Project Risk

A list of common project risks.

## External Risk

The definition of external risk with examples.

## Risk Opposite

The true opposites of risk.

## Project Management Process

An overview of the project management process.

## Internal Risks

The definition of internal risk with examples.

## Project Scope

An overview of project scope with examples.

## Risk Meaning

The meaning of risk with examples.

## Risk Objectives

Examples of measurable risk objectives.

## Program Management Examples

An overview of program management with examples.

## Risk Impact Examples

A list of common risk impacts with a few detailed examples.

## Change Risk

An overview of change risk with a list of examples.

## Facility Risk

An overview of facility risk with examples.
The most popular articles on Simplicable in the past day.

## New Articles

Recent posts or updates on Simplicable.
Site Map