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\begin{document}
\docheader{Introduction to Computing}{1}
{Problem Solving With The STAIR Technique}

\begin{goallist}
\item Students will learn a general problem solving strategy that can be
applied to problems. 
\item Students will learn basic keyboard and mouse usage skills.
\item Students will learn to identify key problem - solving tools in modern
software applications. 
\item  Students will apply problem solving strategies by learning how to
play unfamiliar computer games. 
\end{goallist}

\begin{prereqs}
\item None
\end{prereqs}

\paleGreen
\section{The Problem}

Computers and related technology have become an undeniable part of our
daily existence.  It is almost impossible to live without interacting in some
way with computing technology.  The purpose of this course is to give you
some tools you can use to begin mastering technology.  We will not be able
to make the impact of technology go away, but if we approach it carefully,
we can decide whether our lives are controlled or enhanced by the computers
that surround us.  As the influx of technology grows at unprecedented
rates, we quickly find that our accustomed ways of thinking may need
refinement.  

The 
\begin{gloss*}{universal}
A {\it universal\/} device is one capable of simulating the behavior
of all other devices.
\end{gloss*}
nature of computers makes them much more flexible than the
kinds of machines we may be used to learning.  Because of this flexibility,
we cannot train ourselves to use a computer in the same way we teach
ourselves to use a more mechanical machine, such as a car or a sewing
machine.  When you learn to use one of these traditional machines, you
determine what it is supposed to do, how to make it do that job, and what to
do if it isn't working.  Once you learn one car or sewing machine, the
skill of driving or sewing is relatively easy to transfer to new cars or
sewing machines.  You can expect any car to do the same basic task,
although the cockpit layout may be different, the transmission may require
more skill, and so on.  The same can be said of the sewing machine.  You
might need to learn a new way to install thread into the machine, but the
process of sewing does not substantially change from machine to machine.
In these largely mechanical single purpose machines, you have to
learn only one skill, although that skill may be very complex in nature.  You
don't expect cars to start flying, and you don't expect a sewing machine to
ever suddenly start acting like a microwave.  

As we will see, computers are very different from these machines in at
least one critical way.  While a car or a sewing machine is designed
primarily to do a single type of job, the computer is designed to do many
very different kinds of jobs.  The same computer could be used as a writing
tool, to simulate the effects of a roller coaster, to play parlor games, to
do complex mathematical calculations, and to retrieve stock market quotes
from Tokyo.  These things could conceivably happen at the same time in the
same computer.  The skills you would need to control a computer when it is
helping you edit documents might be very different than the skills you use
to get the stock quotes.  If we approach learning a computer using
the same learning model that has served us well since the beginning of the
industrial revolution, we can never stop learning.  It seems impossible to
learn how to use a computer, because each time we have it do something
else, we have to learn how to control it in that particular context.  Some
of the applications you will want to use a computer for in the next few
years have not yet been invented!

How then, can we hope to teach a class to use a computer?  Many
educators have used the car/sewing machine model, treating each
software application package as a new and distinct machine.  Using this
model, you might learn how to use a specific word processing package, say
WordPerfect 6.0 for windows.  You can learn how to use this system
essentially the same way you learned how to drive or use a sewing machine.
We can feed you a list of commands, take you step by step through a number
of typical processes, and guide you carefully through your first few
projects.  This is a comfortable model of learning, and it works very well
for teaching specific programs.  If you need to learn exactly how to use
WordPerfect 6.0 for Windows, and that's all you will ever use your computer
for, such an approach would be ideal.

Unfortunately, the learning model outlined above has some serious
weaknesses when applied to learning computers and technology.  The first
problem is the universality of computers.  If we teach you word processing,
you have learned something useful, but you really haven't learned much
about computers.  They can do so much more than process words.  As an
educated person, you will be expected to know many other ways to use
computers.  We would not be doing our job if we taught only one type of
application.

Another problem is the pace of changing technology.  It is no
exaggeration to say that any software we install in the lab today will
probably be out of date by the end of the semester.  New releases of major
programs come so frequently that memorizing commands and the layout of the
program is a futile process.  Things will change.  You can't rely on the
menu structure of a program, the control key combinations, or anything else
to stay the same.

Anther weakness in the above model is the variety of programs that are
available in any one category.  If we decide to teach you WordPerfect in
our classes, and you end up working in an office which uses only Word for Windows,
you could be lost.  The commands you have dutifully memorized when the
computer is running one application could do nothing at all in a different
application.  It is conceivable that a command you use to save documents in
one program could be used to delete documents in another.  The potential
for confusion is obvious.

The prospects for ever learning how to use and control a computer sound
quite gloomy, but it is not nearly as bad as it sounds.  If you reflect on
your classmates, family, and friends, you can undoubtedly think of a person
who can sit down at any computer, run a program she has never seen before,
and produce amazing results.  How do these people do it?  Why is it that
some people can run a never - before - seen program and make it do things
for them?  What is their secret?

After studying the way such people work, we have noticed some important
themes: 

\begin{itemize}
\item These people are (generally) not super-intelligent
people who spend their whole lives with computers.  Ordinary people can
learn how to control computers with amazing flexibility and skill.  

\item Skilled computer users usually have a strong general knowledge
about how computers work and what they can do.  They know the main types of
applications that are used on computers, and they know what
features they can expect to find within an application.   

\item Skilled computer users have little fear of technology.  They
frequently use educated guesses to determine how things work, and they
don't worry if their guesses are sometimes incorrect.  Instead, they tend to learn
from mistakes.

\item The most striking characteristic of skilled computer users is the
presence of some kind of organized problem-solving strategy.  Skilled
computer users are skilled problem solvers.  They rely far more on their
ability to solve new problems and find answers independently than on
previous knowledge of the commands of an application program.  They
are able to encounter new programs and situations with little apprehension,
because they are confident their problem-solving ability will help
them overcome lack of knowledge about the new situation.  The
goal of this course is to help you become the type of skilled computer user
we have described above.  We will teach you a framework for problem solving
with computers, and help you apply that framework to various types of
application programs.  We will introduce you to what computers can do
as well as the types of problems you may be able to solve with specific software
applications. You will also be given many opportunities to develop
your problem-solving abilities by using real applications on real computers.  
\end{itemize}

We will not focus on individual software packages, although we will
certainly use them for examples and exercises.  We will be far less
interested in actual commands and methods for doing things, and more
interested in the process you will use to learn how to do these things in
whatever applications you use in the future.  Our goal is to teach you the
skills you will need to learn computing applications that have not even
been imagined yet!

\section{Our Most Powerful Tool - The STAIR Steps for Solving
Problems}

Problem-solving can be seen as more of an art than a science.  Each
person has different ways of approaching problems.  Our intention is not to
limit your problem-solving processes to our way of thinking, but to give
you a framework you can fall back on when you are stuck.  We have developed
a method called STAIR which has proven to be a helpful problem-solving
tool.

STAIR is an acronym.  (Get used to it... Computer scientists LOVE
acronyms!!)  Each letter in the word STAIR represents a part of a general 
problem-solving strategy.

\begin{definition}
\item[\bf S - State the problem] This step seems obvious enough, but it is
often the one people skip.  We frequently start solving problems before we
really think carefully about what problem we are trying to solve.  The
result is confusion and wasted time.  Take the time to describe carefully
to yourself what you are trying to accomplish.  Avoid the temptation to
couch this problem description in technical terms.  At this stage of the
process, all your thoughts should be in ENGLISH (or, of course, whatever
other human language you think most comfortably in). Some problems are best
described with sketches or other tools (like flowcharts and data diagrams)
which will be discussed later.  Use whatever you need to make sure you have a
firm understanding of what you want to accomplish.  It's best to write this
down on paper so the problem statement can be checked later if you get confused.  If
you don't know where you are trying to go, how will you know when you get
there?
 
\item[\bf T - Tools for the job] Once we know what kind of a job we want to
accomplish, we can begin to explore which tools we might use to solve the
job.  We are using the term tool in a very broad sense.  A tool might be a
command, a button on a toolbar, a selection on a drop-down menu, a
strategy, a program, or something else, depending on the kind of job we are
trying to do and the context in which we are working.  Knowing the
capabilities of a certain program, and the kinds of things different types
of computer applications can do are the main ways you add new tools to your
toolbox of computing skills.  As you gain experience, you will constantly
be adding new tools of all kinds to your repertoire.  Even the STAIR
strategy itself can be considered a tool.  Most of the time, there is more
than one tool available to do a job.  At this point, just list the
available tools.  Later on, you will decide which tool or tools to use.  You 
might need to come back to this list if you chose an inappropriate tool the
first time through the process.

\item[\bf A - Algorithm development] An algorithm is a computer science
term for a strategy or plan of action.  Part of developing an algorithm is
choosing an appropriate tool or set of tools from the previous step.  The
other component is determining how those tools will be used to solve the
problem.  As with the other steps, the algorithm can vary widely in the
type and complexity of the strategy you will use.  In simple problems, your
algorithm may be as simple as saying ``I'm going to try pressing this
particular button on the menu bar.''  A more complex problem will probably
require a more complex algorithm.  As before, it is a good practice to
write down your algorithm on paper.

\item[\bf I - Implementation of the algorithm] It is interesting to note
that none of the above steps require the use of a computer.  The
implementation step is the actual process of translating our human
thought into something the computer can understand.  In
simple problems, our algorithm may be implementing a command or
two. Implementation can mean ``just do it'' when we are dealing with these
simple problems.  Programmers think of the implementation step as
translating the algorithm into some type of computer programming language.
The process is the same regardless of the complexity of the problem.

\item[\bf R - Refinement] We like to think if we learn a skill and
prepare ourselves properly, we can solve a problem on the first attempt.
Experience shows us this is not usually the case.  It is normal for a
computer user to attempt a solution several times before the problem is
solved. A skilled problem solver will analyze what happened, review the other steps,
and try again.  Each unsuccessful attempt should bring you closer to an
understanding of the problem and its solution.  Refinement usually means
going back and looking at the previous steps critically.  Ask yourself if
you really defined the problem properly.  If so, have you used all the
possible tools at your disposal?  Are you sure there is not a tool
available that you have overlooked?  Did you choose the best algorithm for
the job?  Did you implement the solution properly?  (You would be amazed at
the number of computer errors that are the result of simple typing or
spelling errors!)  Again, you will find that practice will make you much
more confident at this critical stage of the process.
\end{definition}

\section{Examples}

As you can see, the STAIR process does provide some guidelines for thinking
about a problem, but it is not a rigid technique.  You will have to find
your own variations that work well with the way you visualize and think.
Many times you will find yourself not needing the entire process.  The
STAIR convention is a tool which may supplement your natural
problem-solving processes when they are insufficient to solve your
particular problem.  It can also be used to help you
organize your natural problem solving processes.

\subsection{Example One:  Storing the Boat}

\image[left]{bassboat.gif}
The STAIR process can be applied to situations that have nothing to do with
computing.  As an example, imagine the following situation: Tom
came home one day to be confronted by his wife about the small sailboat
that was filling space in the garage.  She suggested he find a more
efficient way to store the boat than leaving it where she normally parked
her car.  (Her suggestion was couched in somewhat stronger terms than
this.!..)  Being quite a good problem solver, he decided to apply the STAIR
methodology to this problem.

\begin{definition}
\item[{\bf S}tatement of the Problem]
Tom thinks to himself: ``I need to get this boat out of the way.  It needs
to go someplace where it won't be in my wife's way, but with easy
access when I want to go sailing.  I don't want to spend a lot of money
or effort on this problem, and I want a long term solution so I don't have
to deal with this again''.

Notice that Tom started with as simple a statement of the problem as
possible.  He also listed some of the relevant constraints.  He didn't
worry about what the exact solution might be yet.  This may not be the
finished statement of the problem.  Tom may find he needs to come back
and refine his problem statement a little more before he can finish the
solution. 

\item[{\bf T}ools Available]
Tom thinks: ``This job might require actual physical hand tools, and I've
got a pretty good set of the standard tools.  Besides the obvious
definition of the word tool, I might think of some of the main approaches
to solving the problem as tools.  I could hang the boat from the ceiling of
the garage, attach it to the walls, put it in the yard, or rent some
storage space.''

Notice how flexible he was with the term `tool.'  This approach allows Tom
to think of the IDEAS he will choose from, as well as the physical
entities.  In fact, the actual mechanical tools that will be used will be
decided much later in the problem solving process.  It's way too early to
worry about whether he will use a hammer or a screwdriver.

\item[{\bf A}lgorithm]
Tom thinks: ``I'll try hanging the boat from the ceiling.  This seems like
the best approach, because the boat will be ugly in the yard, I can't
afford rental space, and the walls are already full.  I think the boat is
light enough to be suspended from the ceiling safely with some ropes''.

In this instance, the algorithm step involved choosing the best alternative
from the tools step.  At this point, he had made a decision about how he
was going to tackle the problem.  Notice that he also started thinking
about which physical tools (in this case a rope) he would use to help solve
the problem.

\item[{\bf I}mplementation]
Tom says to himself: ``When the time actually came to suspend the boat, I
quickly realized I had more to think about.  I measured the ceiling, found a 
perfect spot, and moved the boat to the floor directly under the
spot. However, I didn't know how exactly to attach the boat to the ceiling.  The
ceiling has wooden rafters in it and obviously I need to attach some sort of
hooks to the rafters.  I also noticed the rope I planned to use was
kind of slippery and might not hold a knot very well.

The implementation step so far has been unsuccessful in the
obvious sense; the boat is still sitting on the garage
floor.  Rather than being discouraged by this, Tom will use
the experience as an information gathering stage for the
next step:

\item[{\bf R}efinement]
Tom thinks: ``The ceiling idea is still a good one, but I don't have
everything I need.  I don't trust this rope, and I need some hooks or
something.  Digging through the toolbox, I found one bicycle hook that will
work fine for the bow of the boat.  I can attach it easily to a rafter,
but I still need to hold up the back end of the boat.  I noticed the straps
I use to carry the boat on top of my car.  They are sufficiently strong enough,
but the ends of the straps are designed to fit in the rain gutter of my
car.  I need to find something that will allow me to attach the straps
securely to the rafters.  I went to the hardware store and found screen
door handles!  They will attach to the rafters and they are the perfect
size to attach the straps to!  I went back home, attached the handles,
hoisted the boat up in the straps, and the problem is solved!''

The refinement step made some visits back to many of the other parts of the
problem-solving process.  Our handyman had to adjust his perception of the
problem.  Attaching the boat to the ceiling was a good idea, but Tom's
first statement of the problem did not specify how he was going to do this.
Finding a way to solve this part of the problem involved combining
algorithm development and tool selection.  The implementation happened in
segments as he found more of the right ideas and tools to solve the
problem.  The process does not always flow in a set order, but because he
used a systematic approach, he always knew how to think about solving the
problem.  Tom knew, for example, that his algorithm was good, but he
would need to rethink his tool selection.  Obviously, plenty of people
solve this kind of problem without ever taking a computer science class.
Tom may not even know that he was using an organized problem solving
technique.  The reason we begin with this problem is to illustrate
that our problem solving-process is really just a somewhat formalized
summary of the techniques we already recognize as problem solving
techniques in many settings.
\end{definition}

\subsection{Example Two: Drawing a Map}
\begin{definition}
\item[{\bf S}tatement of the Problem]
Nancy has moved to a new town and her aunt wants to visit her.  Nancy
wants to use her new computer to draw a map from her aunt's home to
her new house. She decided to use the computer so she can produce
copies easily to send to other friends later.

\item[{\bf T}ools Available]
Nancy thinks carefully about the tools she needs.  She knows her computer
has a drawing program built-in, but she has never used the program.  She
does know how to get to the program and start it up.

\item[{\bf A}lgorithm]
Nancy starts by drawing out the map with pencil and paper.  Now she knows
the image she wants to create.  She will use lines to indicate  streets, squares
for specific landmarks, and text to label the streets and landmarks.  When
she has finished with the picture, she will save it to her disk in case she
needs it again, and print it out to include in her next letter.

\item[{\bf I}mplementation]
Nancy stares at the blank screen.  She doesn't know what to do next. She
knows that she has a number of new smaller problems:

\begin{itemize}
\item She needs to draw some rectangles.
\item She needs to draw some lines.
\item She needs to place some text on the picture.
\item She needs to save the picture somehow.
\item She needs to print the picture somehow.
\end{itemize}

Nancy has a dim recollection of the STAIR process from a computer class in
her distant past.  She wonders if she should apply that process to one of
the smaller problems now.  She decides to start with the rectangles:

\begin{itemize}

\item Statement of Problem:  Nancy needs to draw a rectangle to represent
her Aunt's house.

\item Tools:  She spots a button on the toolbar that has a
picture of a rectangle!   If she doesn't see it there,
she knows she can cruise the menus for a likely looking command, or
check the on-line help.

\item Algorithm:  She decides: ``What the heck.  I'll press
it and see what happens.''

\item Implementation: She presses the button.  The cursor on this
screen changes, and when she drags the mouse on the screen, she is able to
draw a rectangle.  She practices a few times until she has the hang of it.

\item Refinement:  After she knows how to make a rectangle
exactly how she wishes, she puts one where her aunt's house should be on the map.
\end{itemize}

\item[{\bf R}efinement]
Nancy repeats the process to learn the other tools she might need. Most of
the things she needs relate directly to buttons on the toolbar.  She does
not see a button that might represent printing.  She looks in the on-line
help and finds that Print is an option in the File menu.  She then looks
at the menu and finds the command right there.  She uses it and the picture
shows up in her printer.  Problem solved!
\end{definition}

Notice that the problem solving process actually had to occur at two
distinct levels in this project.  First, Nancy had to think about the big
picture of how to draw the map.  As part of this larger problem, she
discovered a number of smaller problems along the way.  She applied the
same kind of process to the smaller problems and was able to learn many new
skills as part of solving the larger problem.  The next time she needs to
use this graphics program, she will already know how to use these
particular tools without having to re-learn them.  In fact, if she tries ANY
graphics program, she will have a head start, because she already knows to
expect some kind of line drawing tool, rectangle tool, and other tools that
she learned to use in this program.

\section{Laboratory Assignment}
\image[left]{labgirl1.gif}
Today in lab you will use a special computer program designed to introduce
you to the most basic computer skills.  You will practice using the
keyboard, editing text, locating special keys, using the mouse, using drop
down menus, and accessing on-line help.  After you finish the program,
you will get to play some games.  The lab instructor will NOT tell you how
to play the games.  It is up to you to figure out how the games work and
how to play them.  Use the STAIR technique to figure out how each game
works.  The lab instructor will demonstrate how to start the program.

\begin{vocab}
\item Computers are universal machines - the same machine can do many
different kinds of tasks.
\item Learning to use computers effectively requires problem solving
ability.
\item The STAIR method is one way of organizing the problem solving process.
\item Statement of Problem:  defining with words, sketches, or other means
what you want to accomplish.
\item Tools:  Concepts, Commands, Menu items, Toolbar buttons, programs, or
ideas that can help you solve a problem.
\item Algorithm:  A strategy for solving a problem.
\item Refinement:  The process of studying an unsuccessful attempt at
problem solving and looking back at earlier steps to approach a solution
\end{vocab}

\section{Summary}
\image[left]{filecab.gif} 
The way we learn about using most machines is not adequate when we are
trying to learn how to use a computer.  Problem solving ability is a major
factor in success with computers.  The STAIR technique for problem solving
is a good way to summarize the problem solving process.  Problem solving is
a fluid process.  It may be necessary to apply the process to a large
problem, to break that problem into many smaller problems, and apply the
same process to the smaller problems. 

%\begin{center}
%\image{STAIR.gif}
%\end{center}

\vspace{4ex}
\subsection{Review Questions}
\begin{enumerate}
\item Think of the way you already solve non-computing problems.

\begin{quest}
Do you have some type of systematic technique for solving problems?
\end{quest}

\begin{quest}
What do you do when you are stuck?
\end{quest}

Can you see some relationship between your current technique and the
STAIR method? 
\end{enumerate}

\hbox{
\begin{minipage}{5.0in}
\begin{enumerate}
\setcounter{enumi}{1}
\item Imagine that your friend calls you and tells you a skunk has gotten
into his basement.  Use the STAIR method to summarize how you will
'de-skunk' the basement.
\item Think of a problem you solved recently.  Describe how you solved the
problem in terms of the STAIR method.  Write down how your thinking fit
with the STAIR steps.
\item As you learn one of the games in today's lab, try to apply the STAIR
technique to learning how to play the game.  Write down the steps of the
STAIR method, and how you used each part of the process to learn the game.
\end{enumerate}
\end{minipage}
\hspace{1em}\hfill
\parbox[t]{1.5in}{\psfig{file=aargh.ps}}
}

% \subsection*[s]{Module Effectiveness Assessment/questions for the committee}
% \begin{rightimage}{\icondir draftab.gif}
% \begin{itemize}
% \ item Does early emphasis on problem solving make development of other
% modules easier?
% \item Can students apply it on non - computer problems such as the review
% questions? 
% \item Can they apply it in the lab when learning the games?
% \item Should we have approached this module using a STAIR organization?
% \item Is the organization sufficient?
% \item Is this the appropriate tone, writing style, audience level?
% \item Is html the correct format for sharing this information?
% \item How do we deal with authorship, copyright issues?
% \end{itemize}
% \end{rightimage}

%\hr[noshade size=2]
%\'169\ 1996, Andy Harris,\\
%IU System-wide Course A/B Development Committee\\
%Indiana University.

\anslist{stairans}
\end{document}

