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Lesson#2
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INTRODUCTION TO HUMAN COMPUTER INTERACTION-2
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Learning Goals
As the aim of this lecture is to introduce you the study of
Human Computer
Interaction, so that after studying this you will be able to:
. Describe the
significance of HCI, particularly adverse impact of computer
technology on humans and reasons for these adverse effects
. Describe the nature
of humans and computers
. Understand the
Paradox of the computing phenomena
. Differentiate
between focus of SE and HCI
2.1 Definition of HCI
“Human-Computer Interaction is a discipline concerned with the
design, evaluation
and implementation of interactive computing systems for human
use and with the
study of major phenomena surrounding them”
-ACM/IEEE
2.2 Reasons of non-bright Aspects
Airplane + Computer
In last lecture we were discussing the incident of airplane.
Today we will look at the
reason of such a fatal incident.
The National Transportation Safety Board investigated, and ---as
usual---declared the
problem human error. The navigational aid the pilots were
following was valid but not
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for the landing procedure at Cali. In the literal definition of
the phrase, this was
indeed human error, because the pilot selected the wrong fix.
However, in the larger
picture, it was not the pilot’s fault at all.
The front panel of the airplane’s navigation computer showed the
currently selected
navigation fix and a course deviation indicator. When the plane
is on course, the
needle is centered, but the needle gives no indication
whatsoever about the
correctness of the selected radio beacon. The gauge looks pretty
much the same just
before landing as it does just before crashing. The computer
told the pilot he was
tracking precisely to the beacon he had selected. Unfortunately,
it neglected to tell
him the beacon the selected was a fatal choice.
The flight computer on Flight 965 could easily have told the
pilots that ROMEO was
not an appropriate fix for their approach to Cali. Even a simple
hint that it was
“unusual” or “unfamiliar” could have saved the airplane.
Instead, it seemed as though
the computer was utterly unconcerned with the actual flight and
its passengers. It
cared only about its own internal computations
Joke in Computer Industry
There is a widely told joke in the computer industry that goes
like this: A man is
flying in a small airplane and is lost in the clouds. He
descends until he spots an office
building and yells to a man in an open window, “Where am I?” The
man replies,
“You are in an airplane about 100 feet above the ground.” The
pilot immediately
turns to the proper course, spots the airport and lands. His
astonished passenger asks
how the pilot figured out which way to go. The pilot replies,
“The answer the man
gave me was completely correct and factual, yet it was no help
whatsoever, so I knew
immediately he was a software engineer who worked for Microsoft
and I know where
Microsoft’s building is in relation to the airport.”
When seen in the light of the tragedy of Flight 965, the humor
of the joke is macabre,
yet professionals in the digital world tell it gleefully and
frequently because it
highlights a fundamental truth about computers:
They may tell us facts but they don’t inform us.
They may guide us with precision but they don’t guide us where
we want to go. The
flight computer on Flight 965 could easily have told the pilots
that ROMEO was not
an appropriate fix for their approach to Cali. Even a simple
hint that it was “unusual”
or “unfamiliar” could have saved the airplane. Instead, it
seemed as though the
computer was utterly unconcerned with the actual flight and its
passengers. It cared
only about its own internal computations
Communication can be precise and exacting while still being
tragically wrong. This
happens all too frequently when we communicate with computers,
and computers are
invading every aspect of our modern lives. From the planes we
fly to just about every
consumer product and service, computers are ubiquitous, and so
is their
characteristically poor way of communicating and behaving.[1]
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I-Drive Car Device
It takes automotive computer power to a whole new level.
Computer systems provide
the car with BMW's most powerful engine, a silky smooth ride and
what is supposed
to be the simplest in-dash control system available. But what is
created for the sake of
simplicity can often time creates the most confusion.
Many controls are operated with a single large, multifunction
knob located in the
console between the front seats. The control consists of a
combination rotary and push
button for selecting functions. Confirmation of the selected
mode is displayed on a
dash-mounted screen.
Users can change functions -- from communications to climate
control, navigation or
entertainment -- by pushing the console knob forward or back, or
side-to-side. By
twisting the knob, they can scroll through menus. And by
clicking a button located in
the middle of the knob, they can select functions.
"iDrive" takes into account the fact that comfort, communication
and driver assistance
functions are only rarely adjusted while driving. The operating
unit in the center
console gives the driver direct access to many other driving
functions and information
and communication options. Several hundred functions can be
controlled with this
device.
A computer-type monitor is positioned directly within the
driver's line of vision to the
road ahead. The large monitor in the center of the dashboard
displays all the
information the driver needs, apart from the speedometer and
tachometer, which are
conventional analog instruments.
The driver slides the dial to choose between multiple control
menus displayed on an in-dash
LCD screen. The driver rotates the dial to move through lists
and pushes the dial axially to
select a list item.
After reading that I didn't feel like I had any sort of idea
what 'axially' meant, but I
suppose this video helps. What concerns me about this is the
interaction with this little
device requires the driver, hurtling down the road, to look at a
screen. They say there
is force feedback that indicates the menu, but that's only half
the equation, because
there are things in the menus. So, I'm guessing the driver needs
to memorize the
menus, which are sure to be short, so think about the mental
modeling here.
To really keep your eyes on the road, you have to be able to do
everything by feel and
pattern. Is this easier than hot-cold air sliders, vent
selection buttons and radio dials?
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It takes 15 minutes to change a Radio Channel. The fundamental
flaw: you absolutely
have to take your eyes off the road to change settings. Result
is constant Calls to Help
Desk
Feature Shock
Every digital device has more features than its manual
counterpart, but manual
devices easier to use. Hi-tech companies add more features to
improve product.
Product becomes complicated
Bad process can’t improve product
Computer + Bank
A computer! Whenever I withdraw cash from an automatic teller
machine (ATM), I
encounter the same sullen and difficult behavior so universal
with computers. If I
make the slightest mistake, it rejects the entire transaction
and kicks me out of the
process. I have to pull my card out, reinsert it, reenter my PIN
code, and then re-assert
my request. Typically, it wasn’t my mistake, either, but the ATM
computer finesses
me into a misstep. It always asks me whether I want to withdraw
money from my
checking, saving, or money market account, even though I have
only checking
account. Subsequently, I always forget which type it is, and the
question confuses me.
About once a month I inadvertently select “savings”, and the
infernal machine
summarily boots me out of the entire transaction to start over
the beginning. To reject
“savings”, the machine has to know that I don’t have a saving
account, yet it still
offers it to me as a choice. The only difference between me
selecting “saving” and the
pilot of Flight 965 selecting “ROMEO” is the magnitude of the
penalty.
The ATM has rules that must be followed, and I am quite willing
to follow them, but
it is unreasonably computer-like to fail to inform me of them,
giving me contradictory
indications, and then summarily punish me for innocently
transgressing them. This
behavior---so typical of computers---is not intrinsic to them.
Actually nothing is
intrinsic to computers: they merely act on behalf of their
software, the program. And
programs are as malleable as human speech. A person can speak
rudely of politely,
helpfully or sullenly. It is as simple for a computer to behave
with respect and
courtesy as it is for a human to speak that way. All it takes is
for someone to describe
how. Unfortunately, programmers aren’t very good at teaching
that to computers.
In order to solve some of these problems, here comes the
relatively new and emerging
field of Human Computer Interaction (HCI).[1]
2.3 Human verses Computer
Human species
Human beings are the most interesting and fascinating specie on
planet. They are the
most complex living being on the earth. It has very much
diversity in its nature. It is
intelligent in its deeds. Human beings think and decide
according to their own will.
Yes, they are free in nature. They like freedom. They think on a
problem dynamically
and they can find many solutions that may not exist before. They
can invent. They are
not only rational but they also have emotions. They also think
emotionally. They act
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emotionally. And fortunately or unfortunately they make
mistakes. They make
mistakes which some time become fatal for them and some time
they become blessing
for them.
Computer species
On contrast, computers are the invention of human being. They
are also complex but
they are also pretty dumb. It can also think but it can’t think
on its own will, it thinks
how it has been directed to think. No doubt its speed is
marvelous. It does not tire. It
is emotionless. It has no feelings, no desires. It works how it
has been commanded to
work. And they do not make mistakes.
Before penetration of computers in our daily life, human beings
were performing their
tasks at their on responsibility. In a business domain human
beings were dealing and
interacting with each other’s. For example a store manager was
dealing with all the
workers performing their different duties in the store. Some one
was registering the
new arrivals of products, some one was numbering the products
and many more…and
store manager has to interact with all these human beings. If
some one was a
salesperson, he used to interact with different clients and used
to deal with them
according to their mood and desire. He could judge their mood
with their tone, their
attitude and with their body language. He could provide answers
relevant to their
questions.
But now in this age of information technology we are expecting
computers to mimic
human behavior e.g. ECommerce systems, now there is no need for
a salesperson.
Web sites are behaving as a salesperson or as a shopping mal.
That is now; a dumb,
unintelligent and inanimate object will perform the complex task
which was
performed by some human being.
2.4 Software Apartheid
Apartheid
Racial segregation; specifically: a policy of segregation and
political and economic
discrimination against non-European groups in the Republic of
South Africa.
[Definition of apartheid]
Software Apartheid
Institutionalizing obnoxious behavior and obscure interactions
of software-based
products. [Definition of software apartheid]
Programmers generally work in high-tech environments, surrounded
by their technical
peers in enclaves like Silicon Valley. Software engineers
constantly encounter their
peers when they shop, dine out, take their kids to school and
relax, while their contact
with frustrated computer users is limited. What’s more, the
occasional unfocused
gripes of the users are offset by the frequent enthusiasm of the
knowledgeable elite.
We forget how far removed our peers and we are from the
frustration and inability of
the rest of the country (not to mention the world) to use
interactive tools.
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We industry insiders toss around the term “computer literacy”,
assuming that in order
to use computers; people must acquire some fundamental level of
training. We see
this as a simple demand that is not hard and is only right and
proper. We imagine that
it is not much to ask of users that they grasp the rudiments of
how the machines work
in order to enjoy their benefits. But it is too much to ask.
Having a computer literate
customer base makes the development process much easier—of their
can be no
doubt—but it hampers the growth and success of the industry and
of society.
Apologists counter with the argument that you must have training
and a license to
drive a car, but they overlook the fact that a mistake with
software generally does not.
If cars were not so deadly, people would train themselves to
derive the same way they
learn excel.
It has another, more insidious effect. It creates a demarcation
line between the haves
and have-nots in society. If you must master a computer in order
to succeed in
America’s job Market beyond a burger-flipper’s carriers, then
the difficulty of
mastering interactive systems forces many people into menial
jobs rather than
allowing them to matriculate into more productive, respected and
better-paying jobs.
Users should not have to acquire computer literacy to use
computer for common,
rudimentary task in everyday life. Users should not have to
possess a digital
sensitivity to work their VCR, microwave oven, or to get e-mail.
What’s more, should
not have to acquire computer literacy to use computer for
enterprise applications,
where the user is already trained in the application domain. An
accountant for
example, who is trained in the general principles of accounting,
should not have to
become computer literate to use a computer in her accounting
practice. Her domain
knowledge should be enough to see her through.
As our economy shifts more and more onto information bases, we
are inadvertently
creating a divided society. The upper class is composed of those
who have mastered
the nuances of differentiating between “RAM” and “Hard Disk”.
The lower class is
that who treat the difference inconsequential. The irony is that
the difference really is
inconsequential to any one except a few hard-core engineers. Yet
virtually allcontemporary
software forces its users to confront a file system, where your
success
fully dependent on knowing the difference between RAM and disk.
Thus the term “computer literacy” becomes a euphemism for social
and economic
apartheid. Computer literacy is a key phrase that brutally
bifurcates our society.
But about those people who are not inclined to pander to
technocrats and who can not
or will not become computer literate? These people, many by
choice, but most by
circumstances, are falling behind in the information revolution.
Many high-tech
companies, for example, would not even consider for employment
any applicant who
does not have an e-mail address. I’m sure that there are many
otherwise qualified
candidates out there who cannot get the hired because they are
not yet wired. Despite
the claims of the Apologists, using e-mail effectively is
difficult and involves a
significant level of computer literacy. Therefore, it
artificially segregates the work
force. It is the model equivalent of the banking technique of
“red lining”. In this
illegal procedure, all houses in a given neighborhood are
declared unacceptable as
controller for a housing loan. Although the red lines on the map
are ostensibly drawn
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around economic contours, they tend to follow racial lines all
too closely bankers
protest that they are not racists, but the effect is the same.
When programmers speak of “computer literacy”, they are drawing
red lines around
ethnic groups, too, yet few have pointed this out. It is too
hard to see what is really
happening because the issue is obscured by technical mythology.
It is easy to see---
regardless of how true---that a banker can make a loan on one
house as easily as on
another. However, it is not easy to see that a programmer can
make interactive
products easy enough for people from lower socio-economic
backgrounds to use.
“Acceptable levels of quality for
software engineers
are
far lower
than are those for traditional
engineering disciplines”
“Software-based products not INHERENTLY hard to use
Wrong process
is used to develop
them” [1]
Software Engineering and HCI
There is a basic fundamental difference between the approaches
taken by software
engineers and human-computer interaction specialists.
Human-computer interface
specialists are user-centered and software engineers are
system-centered.
Software engineering methodologies are good at modeling certain
aspects of the
problem domain. Formal methods have been developed to represent
data,
architectural, and procedural aspects of a software system.
Software engineering
approaches deal with managerial and financial issues well.
Software engineering
methodologies are useful for specifying and building the
functional aspects of a
software system.
Human-computer interfaces emphasize developing a deep
understanding of user
characteristics and a clear awareness of the tasks a user must
perform. HCI specialists
test design ideas on real users and use formal evaluation
techniques to replace
intuition in guiding design. This constant reality check
improves the final product.
References
. [1] The Inmates are
running the asylum by Alan Cooper.
. [2] Human Computer
Interaction by Jenny Preece. |
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