Arguments

model (3)

1. models are intended to be useful, not perfect

2. different models allow you to perceive and understand same situation differently

3. some models are predictive, some are explanatory

what is making an argument

every time you model the world or define the world you dream of or want to create

toulmins structure of argument

ground —> claim (justification, evidence, qualifier, counterclaim) —> acceptance

qualifier

constrains the scope of argument and acknowledges limitations.

Perry Model of intellectual and ethical development

1. recognizing uncertainty and ambiguity from Authority

2. recognizing opinion as insufficient

3. joining values and analysis with authorities

4. willing to change if better information appears

frame

understand the situation. whats the problem (need, fundamental problem or opportunity. adresses why

what must be done to meet needs? (goals, specify what system should accomplish to satisfy needs) addresses what we need to do

what are expectations of the solution (objectives, detail specific actions or criteria necessary to achieve goals) addresses what solution needs to do or be in order to meet goals

diverge

come up with lots of ideas

represent

sketch, report, photograph, model, argue, present, prototype, build

converge

throw some ideas away. viable alternative (requirements), how does alternative measure (based on metrics with measurement process), how do alternatives compare (evaluation criteria)

NGOs originate from

needs, goals, objectives all originate from stakeholders and must be negotiated and agreed upon by all parties.

stakeholders

impacts and impacted by design

requirements

specific, verifiable, necessary

evaluation criteria

measure of performance, what makes a design good

converge order

1. how does alternative measure (informed by requirements)

2. is this alternative viable (based on metrics)

3. how do these alternatives compare (informed by evaluation criteria)

evaluation criteria

utility (goodness, desirability, preference) vs characteristic (in a unit from a metric)

the further a claim is from the ground…

the more evidence and justification it requires to be acceptable

ground —> analytical claim (what, generate understanding) —> interpretive claim(so what, generate agreement) —> speculative claim (what could be, generate ideas) —> crazy idea

ways to support claims

1. research

2. testing, calculating, modelling

3. sketching, low fidelity prototyping for proof of concept

toulmin structure of argument recommended order

ground

claim

justification

qualifier

evidence

DFX design for x

design for x principles help define specific requirements or evaluation criteria around common goals and objectives based on ways of achieving the desired outcome

codified in handbooks

three reliability metrics

mean time to failure (MTTF): how long will a component work before failing

mean time between repairs (mtbr): how long will al component work before needing work

mean time to repair (mtr): when it breaks how long will it take to fix

reliability of the device is

the product of the reliabilities of its components

rp = r1 x r2 x r3

what do dfx handbooks tell you

shows you principles which you can use to make objectives then make requirements

how do you evaluate how good a design is

frame converge diverge