Name: Loka Abhishek
Subject: CS 5326 ID#2
ADVANCED HUMAN FACTORS
ASSIGNMENT 2: ATM MACHINE
NAME: Abhishek loka
MAIL ID: AL1291@TXSTATE.EDU
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Name: Loka Abhishek
Subject: CS 5326 ID#2
The aim of this assignment is for you to elicit mental models from people. In
particular, the goal is for you to understand the nature of people’s knowledge
about an interactive product in terms of how to use it and how it works.
(a) First, elicit your own mental model. Write down how you think a cash
machine (ATM) works. Then answer the following questions (abbreviated
from payne,1991):
An ATM is simply a data terminal with two input and four output devices. Like any
other data terminal, the ATM has to connect to, and communicate through, a host
processor. The host processor is analogous to an Internet service provider (ISP).
ISP is the gateway through which all the various ATM networks become available to
the cardholder.
How much money are you allowed to take out?
A regular ATM card has a maximum cash withdrawal limit of $300 per day. A Visa Debit
Card has a maximum of $500 in cash, $2,000 in purchases with a total of both cash and
purchases of $2,000 per day.
If you took this out and then went to another machine and tried to withdraw the
same amount, what would happen?
We cannot withdraw the money from another ATM machine. The ATM machine will not
allow us to do that.
What is on your card?
ATM card contains a unique card number and some security information, such as an
expiration date or CVC (CVV).
How is the information used?
ATM will ask you to do the following:
You will be asked to slide your card through a dot that reads the information
contained in the magnetic stripe on the back of your card.
The ATM will then ask you to enter the amount to be withdrawn.
You will be asked to punch in your PIN, or secret code
The ATM will press a key that initiates an automatic phone call to your bank or
credit union. This confirms that the money is available in your account. Once
confirmed, your bank or credit union automatically deducts the amount from
your account.
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Name: Loka Abhishek
Subject: CS 5326 ID#2
What happens if you enter the wrong number?
You have three attempts to enter your PIN correctly. If you enter the wrong PIN three
times in a row, your card will be 'locked'. If your card becomes 'locked', keep hold of it
and then contact the bank immediately.
Why are there pauses between the steps of a transaction?
It verifies the data entered by the user after every step of transaction. Hence, there is a
pause after every step of transaction.
How long are they? What happens if you type ahead during the pauses?
Generally, the pause between every step of transaction is 2 to 4 seconds. It does not
accept the input given by the user during the pauses.
What happens to the card in the machine?
The card reader captures the account information stored on the magnetic stripe on the
back of an ATM/debit or credit card. The host processor uses this information to route
the transaction to the cardholder's bank.
Why does it stay inside the machine?
Inside the machine, the card reader captures the account information stored on the
magnetic stripe on the back of an ATM/debit or credit card.
Do you count the money? Why?
If my transaction is inaccurate, I cannot discuss it with the machine. Thus, there is no
need to count my money at the ATM and risk exposing my money to a thief.
Next, ask two other people the same set of questions.
(b) Now analyze your answers. Do you get the same or different explanations?
What do the findings indicate? How accurate are the people’s mental
models of the way ATMs work? How transparent are the ATM systems they
are talking about?
Most of the answers, answered by two other people are incorrect. The findings
indicate that they are not aware about the working of an ATM. The people’s
mental models are hypothetical. It is impossible to implement their working model
in reality.
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Name: Loka Abhishek
Subject: CS 5326 ID#2
(c) Next, try to interpret your findings with respect to the design of the system.
Are any interface features revealed as being particularly problematic? What
design recommendations do these suggest?
The input entered through buttons is being problematic to a section of users.
Instead, the input taken through touch screen would be a better alternative.
(d) Finally, how might you design a better conceptual model that would allow
users to develop a better mental model of ATMs (assuming this is a desirable
goal)?
The input entered through buttons is being problematic to a section of users.
Instead, the input taken through touch screen would be a better alternative.
The ATM machine should work 24 hours a day. In case the ATM machine fails,
an alternative ATM machine should be arranged in emergency.
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Name: Loka Abhishek
Subject: CS 5326 ID#2
References:
Lecture notes of JOHN DURRETT
http://money.howstuffworks.com/atm2.htm
http://ask.metafilter.com/44472/Are-ATMs-the-perfect-machine
http://www.pueblo.gsa.gov/cic_text/money/shopwith-atmcard/shop-atm.htm
http://ci.golden.co.us/Page.asp?NavID=105
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