How Good is Good Enough?

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					  How Good is Good Enough?
           Collins, Robert, Keith Miller,
         Bethany J. Spielman, and Phillip
          Wherry. Communications of the
         ACM January 1994, vol. 37, no 1.

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          How Good is Good Enough?
Significant software when first released will contain
errors.

Software that matches specifications perfectly can
contain errors if specifications are not perfect.

Software that matches specifications perfectly and
has perfect specifications can be used erroneously
by users.

So what we are really talking about is when to release
software and how to protect against the inevitable
errors.
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                  Sample Case
At Mercy Hospital, Rachel, the vice president in charge
of records and automation, and George, the chief
pharmacist, agree that computerization has the
potential for increasing the efficiency of the pharmacy.

Rachel and George then seem to do everything right.
They produce a specifications document which they
get approved. They hire consultants to design and
implement the system and provide them with specifi-
cations for testing procedures. They hire Helen as the
consultant to install the system and train the doctors,
nurses, and pharmacists who will use the system.

Problems that arise include two near mishaps, com-
plaints concerning too much typing, and disagreement
from doctors with computer generated advice.
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                  More Details
The old system had problems and it was in part with
the thought that the new system would be safer, that
the new system was developed and installed.

The system did not identify the source of changes to
the data base so that when problems arose it was not
clear if they were system or operator errors.

Part of the new system was built on a large warehouse
inventory program that had been in use for almost
five years.

The amount of typing involved sort of grew and
caught everyone by surprise.

Ann Frederick, a nurse and vocal critic, caught both
problems.
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          Rawlsian Approach

We observe that participants of society interact
with one another in cooperation and conflict.
"They cooperate since they can achieve a
better life together than they could alone, they
contend since they are personally affected by
how the benefits of their cooperation are
distributed."




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          Rawlsian Approach


Rawls proposes that the social contract be
created in a negotiation session conducted by
members of society in which the participants
do not know how any alternatives will affect
their own positions. They must evaluate
scenarios in which they could become the
most or least favored party.



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 Software Process Principal Actors

1. Software provider

2. Software buyer

3. Software user

4. Penumbra (Anyone else who could be
affected by the software).


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                    Principles
If we apply a Rawlsian negotiation scheme to our
software problem, we would probably arrive at the
following principles.

1. Least Advantaged. Don't increase harm to the least
advantaged.

2. Risking Harm. Don't risk increasing harm in already
risky situations.

3. Publicity Test. Use publicity test for difficult cost
benefit trade-offs. [Make only those decisions you can
defend with honor before an informed public.]
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                      Analysis
1. Identify the players.

2. Review the three Rawlsian principles.

 For the least advantaged sometimes you can use the
focus of criticism/concern as representative. Most of
the time you simply select someone to be advocate.

Risking harm

Publicity test. Can everybody make the case that the
software is safe?

3. Analyze responsibilities of the players and identify
actions each player could take to advance the three
Rawlsian principles.
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    Software is not a typical product
1. Software errors can remain after extensive testing.

2. It is difficult/impossible to construct uniform software
standards which could be subject to regulation and
inspection.

3. Software affects an increasingly large number of
people.

4. Anybody can produce software.

5. Software threats tend to be dispersed.

Because the dangers of software cannot be controlled
well, there are additional ethical responsibilities to
minimize risk.
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                   Guidelines
            From "How Good is Good Enough"

1. Providers have an ethical responsibility to do a
thorough, careful job when writing their bids or
contracts.

2. Do not increase harm to the people most vulnerable
or increase risk in an already risky situation.

3. Software developers and buyers have a responsibility
to be open and honest about capabilities, safety, and
limitations of the software in communication with
customers, employees, others who are affected by it,
and the public, where appropriate.
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             Guidelines Cont.
         From "How Good is Good Enough"


4. Developers and buyers have an obligation to
properly train users. Buyers and users have a
responsibility to understand the limitations of the
software and its proper operation.

5. Developers and buyers should include users in
the planning and testing stages to improve safe
functioning of the system.



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Software Flaws Cost the Country a
             Bundle
          --25 & 27 June 2002 National Institute of
          Standards and Technology(NIST) Study

"buggy software" costs the US $59.9 billion annually,
with the lion's share of the burden falling on
consumers. Better testing could reduce the cost by
as much as 1/3, or $22 billion. (Interesting math)




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              Quote of the Week
          (from CIO Magazine, July 1, 2002)


Kevin Turner,CIO of Walmart, says,"I'd really like to see
our technology vendors step up and help us with these
[security] vulnerabilities because the money that we
are pouring into security right now is being pulled away
from development and strategic things that we could be
investing in. A lot of the vulnerabilities that we deal with
are preventable and could be avoided if the technology
vendors would do the due diligence to tighten up
[the security configuration of] their products."

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