How Big Is It? A guide to agile estimation and planning

Mike Pearce How big is it?

#bestTalkEver

Introduction

@mikepearce /mikepearce.net [email protected] /in/mikeypearce

What is estimating? The art of estimating Planning What it
really means

Unluckily all these positive assertions are contrary to that very
experience, which is pleaded for them, nor have we any idea of self, after the manner it is here explain’d. For from what impression cou’d this idea be deriv’d? This question ’tis impossible to answer without a manifest contradiction and absurdity; and yet ’tis a question, which must necessarily be answer’d, if we wou’d have the idea of self pass for clear and intelligible. It must be some one impression, that gives rise to every real idea. But self or person is not any one impression, but that to which our several impressions and ideas are suppos’d to have a reference. If any impression gives rise to the idea of self, that impression must continue invariably the same, thro’ the whole course of our lives; since self is suppos’d to exist after that manner. But there is no impression constant and invariable. Pain and pleasure, grief and joy, passions and sensations succeed each other, and never all exist at the same time. It cannot, therefore, be from any of these impressions, or from any other, that the idea of self is deriv’d; and consequently there is no such idea. But there is no impression constant and invariable. Pain and pleasure, grief and joy, passions and sensations succeed each other, and never all exist at the same time. It cannot, therefore, be from any of these impressions, or from any other, that the idea of self is deriv’d; and consequently there is no such idea.

What is estimating? Estimation problems Planning What is estimating?

"Estimation is the process of finding an estimate, or approximation,
which is a value that is usable for some purpose even if input data may be incomplete, uncertain, or unstable." Wikipedia "Estimation is the process of finding an estimate, or approximation, which is a value that is usable for some purpose even if input data may be incomplete, uncertain, or unstable." "Estimation is the process of finding an estimate, or approximation, which is a value that is usable for some purpose even if input data may be incomplete, uncertain, or unstable." by ~jjjohn~ - http://flic.kr/p/4CYJT1

Guessing?

Wikipedia [A Guestimate] is defined as an estimate made without
using adequate or complete information, or, more strongly, as an estimate arrived at by guesswork or conjecture. [A Guestimate] is defined as an estimate made without using adequate or complete information, or, more strongly, as an estimate arrived at by guesswork or conjecture. [A Guestimate] is defined as an estimate made without using adequate or complete information, or, more strongly, as an estimate arrived at by guesswork or conjecture. by ~jjjohn~ - http://flic.kr/p/4CYJT1

What is estimating? Estimation problems Planning What it really means
The art of estimating

The lone ranger

Delphi Method

Wideband Delphi

Unluckily all these positive assertions are contrary to that very
experience, which is pleaded for them, nor have we any idea of self, after the manner it is here explain’d. For from what impression cou’d this idea be deriv’d? This question ’tis impossible to answer without a manifest contradiction and absurdity; and yet ’tis a question, which must necessarily be answer’d, if we wou’d have the idea of self pass for clear and intelligible. It must be some one impression, that gives rise to every real idea. But self or person is not any one impression, but that to which our several impressions and ideas are suppos’d to have a reference. If any impression gives rise to the idea of self, that impression must continue invariably the same, thro’ the whole course of our lives; since self is suppos’d to exist after that manner. But there is no impression constant and invariable. Pain and pleasure, grief and joy, passions and sensations succeed each other, and never all exist at the same time. It cannot, therefore, be from any of these impressions, or from any other, that the idea of self is deriv’d; and consequently there is no such idea. But there is no impression constant and invariable. Pain and pleasure, grief and joy, passions and sensations succeed each other, and never all exist at the same time. It cannot, therefore, be from any of these impressions, or from any other, that the idea of self is deriv’d; and consequently there is no such idea. Unluckily all these positive assertions are contrary to that very experience, which is pleaded for them, nor have we any idea of self, after the manner it is here explain’d. For from what impression cou’d this idea be deriv’d? This question ’tis impossible to answer without a manifest contradiction and absurdity; and yet ’tis a question, which must necessarily be answer’d, if we wou’d have the idea of self pass for clear and intelligible. It must be some one impression, that gives rise to every real idea. But self or person is not any one impression, but that to which our several impressions and ideas are suppos’d to have a reference. If any impression gives rise to the idea of self, that impression must continue invariably the same, thro’ the whole course of our lives; since self is suppos’d to exist after that manner. But there is no impression constant and invariable. Pain and pleasure, grief and joy, passions and sensations succeed each other, and never all exist at the same time. It cannot, therefore, be from any of these impressions, or from any other, that the idea of self is deriv’d; and consequently there is no such idea. But there is no impression constant and invariable. Pain and pleasure, grief and joy, passions and sensations succeed each other, and never all exist at the same time. It cannot, therefore, be from any of these impressions, or from any other, that the idea of self is deriv’d; and consequently there is no such idea. 263

Is there a best way to estimate?

“Ideal Time”

By slworking2 - http://flic.kr/p/cvY16A

We suck at Temporal Estimation

Vierordt’s Law (1968): Retrospectively, "short" intervals of time tend to
be overestimated, and "long" intervals of time tend to be underestimated. Vierordt’s Law (1868): Retrospectively, "short" intervals of time tend to be overestimated, and "long" intervals of time tend to be underestimated. 1818 - 1884

(Buehler & Griffin, 2003; Buehler, Griffin, & MacDonald, 1997; Buehler,
Griffin, & Ross, 1994; Bueh ler, Messervey, & Griffin, 2005; Byram, 1997; Connolly & Dean, 1997; Francis Smythe & Robertson, 1999; Grif fin & Buehler, 1999; Jorgensen & Sjoberg, 2001; Josephs & Hahn, 1995; Koneçni & Ebbesen, 1976; König, 2005; Koole & Van’t Spijker, 2000; Kruger & Evans, 2004; MolokkenOstvold & Jorgensen, 2005; NewbyClark, Ross, Buehler, Koehler, & Griffin, 2000; Taylor, Pham, Rivkin, & Armor, 1998)

Sounds bad, what’s the solution?

RAE’s

Time? Effort? Anything? NO

Relative, arbitrary estimates

Fibonacci

Fibonacci 1, 1, 2, 3, 5, 8, 13, 21, 34,
55 ...

Modified Fibonacci 0, 1, 2, 3, 5, 8, 13, 20,
40, 100, ?

Story Points 0, 1, 2, 3, 5, 8, 13, 20,
40, 100, ?

0 1 2 3 5 8 13 20 40 100
=3 (or, as big as a 1 and 2) Bigger than a 1, a 2 AND a 3 Too big

Let’s build a thing with Audience Participation!

3 8 13 8 2 1 3 8 5 8
1 5 Gut feel for sprint 1 Priority order

Pop Quiz Hotshot!

Cone of uncertainty

4x 1x 0.25x 1.25x 1.5x 2x 0.8x 0.67x 0.5x Time
Estimate variability Cone of uncertainty

Begin sprint 1

Velocity = 13

5 8 13 8 2 1 3 8 5 8
1 5 Sprint 1 successful Priority order Sprint 2 Sprint 3 Sprint 4 Sprint 5 Sprint 6 Velocity: 13

Begin sprint 2

Velocity = 15

5 8 13 8 2 1 3 8 5 8
1 5 Sprint 1 successful Priority order Sprint 2 successful Sprint 3 Sprint 4 Sprint 5 Velocity: 13 Velocity: 15

4x 1x 0.25x 1.25x 1.5x 2x 0.8x 0.67x 0.5x Time
Estimate variability Cone of uncertainty Sprint 2

And that’s all there is to arbitrary, relative estimates... Simple,
right?

Also...

Tshirt sizes XS, S, M, L, XL

Cycle Time How long does it take for one story
to get from here to here. To do In Progress Testing Done In 12 days, we will be here s m m s s

How Big Is It? A guide to agile estimation and ...

How Big Is It? A guide to agile estimation and planning

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