Download 3. Personal data

Data
Raw facts and figures – on their own they have no meaning
e.g. readings from sensors, survey facts
Information
Data which has been processed by the computer. It has a
context which makes it meaningful
Knowledge
Is derived from information by applying rules to it.
Using information to make decisions
Data:
1,12, 1.4,2, 12, 1.2, 3,16, 1.1
Information:
Swim times for 100m
Swimmer No
Age group
Times (mins)
1
12
1.4
2
12
1.2
3
16
1.1
Knowledge:
Swimmer No 2 is the fastest in the age group.
Data types
• Boolean
– Can hold one of two values – true/false, YES/NO 1/0
e.g are you disabled?
• Integer
– Holds whole numbers only e.g. school years 7 8 9 10
• Real
– Holds decimal numbers e.g. for storing currency
• Text/String
– Holds any alphanumeric character, can include
numbers and symbols
e.g name address postcode tel no
Coded Data
Advantages
• Save memory
• Faster to type in
• Less likely to have transcription errors
• Greater consistency of data
Disadvantages
• Value judgments fitting into a certain category or
group
• Coarsen data by fitting itHow
into
groups
clever
am I ?
•Thick
•Average
•Very
•Genius
Good quality information is up-to-date,
accurate, and
complete, relevant and correctly targeted
•Add value by aiding decision making Decision-making is based on
information that is available at the time and if this is either out-of-date or
incomplete then this can have a bad effect on the organisation or company.
•Monitor progress. Information obtained by market research (e.g. people in
the street stopping certain passers-by, questionnaires sent to a sample of
homes) and sales figures can help to achieve this.
•Can target reasoning and strategy making e.g. buy more of a certain
commodity because sales are good. Advertising and marketing a product
should be aimed at people likely to buy it otherwise it is a waste of time and
money.
•Gain advantage over competitors. Information can tell an organisation how
well it is doing compared to its competitors. For example information can
identify gaps in a particular market which can then, on the basis of sound
information be filled.
Cost of information
3 categories
•Money
•Time
•Human resources
Collecting the
data
Data entry
Data collected directly
The organisation or company has to produce a way of
collecting information e.g. creating forms, questionnaires,
sampling etc. In the case of forms and questionnaires,
these will have to be printed, sent out and collected. Not
all people respond to forms or questionnaires so many more
will have to be sent out in order to get a fair sample back.
Often, an incentive is given to encourage people to respond
e.g. your name being entered into a free prize draw if the
form is completed and returned.
Data collected indirectly
The organisation may have to buy the information or pay a
third party to gain access to data.
Keying in
Data keying takes time and staff will have to be paid to do
it.
Direct input
There are automated methods of data entry - optical mark
readers (OMR), optical character recognition (OCR), bar
code readers, etc. Specialised hardware/software needs
to be purchased and staff trained to use them.
Data processing
Once the data has been inputted it needs to be processed
into information. This requires hardware and software
resources. The software may be ‘off the shelf’ or it may
have been developed specifically for the organisation or
company. Either way it will cost money.
Data
maintenance
There are costs involved in making sure that data remains
accurate and up-to-date. For example, an organisation
maintains a database of its customers. The database will
only remain accurate and up-to-date if changes to
customers’ details are reported and then updated. This
involves communication with customers and checking that
their details are correct.
Methods used include:
The task of keeping data up-to-date is expensive.
frequent updating (typing in the changes)
frequent collecting of data through questionnaires, letters or checksheets
interactive systems where a person can update his/her own detail
deleting out-of-date data or data which is no longer needed
making sure that all copies of the data are updated so that everyone uses the
same, amended data.
Example 2
It is no good having a mailing list when the addresses are no longer correct.
When people move house, mail continues to be sent to the old address until the
relevant mailing list is updated.
Companies who sell their products through direct mail (junk-mail is the more
commonly used name!)need up-to-date lists of names and addresses of people who
are likely to be interested in their product.
An out-of-date list is of no value whatsoever.
Remember people move house, grow old, die, and change their interests or buying
habits.
Errors on data entry
Verification is the process of checking that data has been correctly
copied from one media to another.
Visual checking for errors.
Double entry keying
Types of errors that can be found;
•Transcription /typing errors
Typing in the wrong character by accident egg 2 instead of a 7
•Transposition Errors
i.e. keying in, in wrong order
e.g. 56789 instead of 57689
Validation is the process of ensuring data is valid and legal.
•Format checks
e.g. date is 2002/ 09.11 instead of 11/09/02
•Input masks e.g. entering data in a controlled way Postcode if LLNN NLL
•Input mask on a date 99/99/99
Validation type
Explanation
Example
Range checks
Data is between stated ranges
Admission No must be between 1
and 9999999999
Format checks
Dates
12/04/03
Presence checks
There must be a character present
ina particular place e.g. the
first 2 letters must be YR to
represent year
YR7
Check digits
No added to a code
Bar codes on library tickets
Date of birth
Format checks 12/09/95
Range check between 1/9/86 –
31/8/94
Input masks 99/99/9999
Admission no
Library code
Presence check e.g.
YGA 123454 ( must start with YGA)
Check digit
Gender
M or F
Advantages of using ICT
•
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Speed of processing
Accuracy of processing of repetitive tasks
Fast transmission speeds
Different output formats graphs reports etc
Save and edit work in future
Factors affecting the efficiency of
use of ICT
• GIGO
• Suitability of hardware and software for
task
• Level of user ability
• Changes in circumstances of during
development of the computer system
• Poor implementation and maintenance
procedures
• Cost restrictions on solution
HCI’s
• GUI’s Windows Icons Menus pointer,
online tutorials – good for inexperienced
user . Children.
• Dos text based has short cut keys- expert
user
• Menu driven when want to limit choices
• Voice
• Specialists e.g. touch sensitive
Flatfiles vs relational databases
Database
–A large collection of related files of data items and links between them, structured in
a way that allows it to be accessed by a number of different applications programs.
File
–a collection of related records
Records
–The basic unit of data stored in a data file.
–It is a collection of items which may be different data types, all relating to the
individual or object the record describes.
–It is treated as a unit for processing.
Fields
–Is part of a record designed to hold a single data item of a specified type.
–Holds data items of the same data type
Primary Key
–It is a unique value which is used to identify a record.
Members
Bookings
Staff
Members
Bookings
Members
Staff
Staff
Flatfile
Relational
database
Advantages
Disadvantages
Minimise s data duplication
More expensive to create
Ensures data consistency
DBMS needs full time maintenance
Ensure data integrity
Controls data redundancy
Computer Assisted Learning (CAL)
Tutorials
Special needs pupils;
Spelling programs which have an interactive component
testing student with games, quizzes and tests.
A scoring system allows students to assess their progress.
Often after 3 tries the answer or clues will be given to them.
Picture and sound are used to enhance the experience.
GCSE revision programs
DISTANCE LEARNINGStudents not always be in the same place as the teacher.
Distance learning course where the tutor is in North Wales. Students are provide
with course booklets and practical work and videoconferencing is used to discuss
problems that ariseAssignments are marked electronically.
Online courses e.g Open University
These can be intranet based in universities or Internet based.
Some university modules are completely computer based with knowledge sections
and task sections. The software records how much of the course you have
covered and if you do not complete the full module you will fail the module..
E – learning sites are now available. Subscribers can even do A levels online
approved by exam board such as OCR. Schools in England are given E-learning
credits which they can use to purchase online courses.
Chat rooms to discuss courses and problems with tutors.
Advantages of using ICT FOR TEACHING AND LEARNING
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Greater interactivity holds a pupils attention.
Quicker feedback in online tests
Offers a variety of different ways to learn and a variety of information sources.
Allows user to learn at own pace and can learn at times suitable for themselves.
Allows user to ‘go over’ earlier work again in case they did not understand i.e repeat
sections they found difficult earlier.
Computer based training significantly reduces costs for the employers and can be
safer if it is a danger
Advantages of using ICT FOR ADMINISTRATION
• Improved speed of access to data - faster searches/ e.g looking for all the pupils in a
particular form and faster sorts e.g. listing pupils by alphabetical order of Surname.
• A variety of output formats available e.g. printed reports, mailmerged documents. Etc.
– Faster and simpler to transfer data e.g. exam entries
• Saves time when reproducing standard letters e.g. lettes to parents informing them
about parents evenings, school sports day programs. Such documents will only have
minor changes each year.
• Increased security
• Saves on storage/office space
Problems with using ICT in Education
ICT is expensive and requires a great deal of capital investment which is
constantly updated and has to be maintained.
Maintenance contracts can run into thousands of pounds which takes money away
from traditional teaching materials such as books.
Unfair distribution of ICT resources and hence learning opportunities.
Richer schools will have greater resources.
Cuts down on social interaction skills
Some educationalists argue that younger pupils do not have as great an
opportunity for group learning.
Text messaging has been blamed for a reduction in spelling skills because of the
use of abbreviations.
Lack of personal support.
Distance learning does not provide the personal support needed by most students
as and when they need it, particularly crucial when a student lacks confidence or
cannot interpret the written instruct
Over reliance e.g. if there is a power cut you cannot use it.
Wordprocessing / DTP
Editing
Alter text and graphics and save
Formatting
Text styles, paragraph styles, bullets etc
Templates
Master documents which are stored have
predefined layout e.g. letter headed notepaper
Style sheets
Have predefined indents, tab settings and
subheading styles
Spreadsheets
Graphs
Easy to read data in graph form than in lists
or tables. Instant transfer understanding
Templates
Saves redoing layout for a firm spreadsheets
each time.Standardises image.
Statistics
Use of commonly used standard functions
such as SUM AVERAGE etc saves time
Presentation Software
•Templates
Background styles and themes with each slide
being the same as the master slide. Has same
logo colour scheme layout etc
•Animated transitions
Movement and direction of text and picture.
Graphical display when moving from one slide to
another
•Formatting
Use of font styles and sizes bullet point scheme for
headings and subheadings
Web Authoring
• Frames to work in and control layout
• Hyperlinks to other web pages
• Hotspots are hyperlinks on graphics/
pictures to other web pages or other parts
of the web page
• Bookmarks are hyperlinks internally to
other parts of the web page
• HTML language code for creating web
pages
CAD
Computer Aided Design
Feature
Definition
Advantage
Hatching or rendering
Different finishes or
materials can be dispalyed
Can do many ‘what if ‘
type investigations to
explore the best finishes
Zoom
Enhance parts of a
drawing to make it bigger
To produce work of more
detail or add detailed
design
Rotate
Rotae in 3D across X Y
and Z axis
See design from all angles
on the outside
Walkthrough
Visit rooms etc in 2D
Allows spatial awareness
of what the design looks
like in relation to other
features
Costings
Produce estimate of cost
of building materials
Automatic estimates are
given and designer can
investigate different
options or work within a
budget.
Stress and strain
Working out the weights
materials can take
Avoids disasters later on
when building as the
designer should build well
within the safety
requirements
Wire drawings
See design without any
finiahes or solid form
Helps with perspective
and working out stresses
and strain areas
Hazard
Prevention
RSI repetitive strain injury caused by prolonged
working at computers or computer games
Ergonomic keyboards ; wrist and foot supports: correct
chair positioning
Eye Strain and epileptic fits
Non flickering screens; Screen filters t remove glare;
correct lighting in the room
Back problems
Adjustable chairs; foot supports:; tilting screens
Ozone irritation from laser printers
Locate personal laser printer 1 metre away from user
Radiation affects embryos leading to miscarriages
No real evidence for this
Expert Systems
• An expert system is a computer system
which emulates the decision-making ability
of a human expert.
• A knowledge-based system which attempts to
replace a human 'expert' in a particular field.
• It diagnoses problems and gives advice on
that the cause of those problems are. They can
also give advice on solutions.
Medical diagnosis
The computer does not take the place of the doctor but can be used to help the
doctor make decisions.
An expert system would have information about diseases and their symptoms,
the drugs used in treatments etc.
A patient is asked by a doctor about symptoms and the replies are input to
the expert system. The computer searches its database, uses its rules and
makes suggestions about the disease and its treatments. Sometimes
probabilities are assigned to diagnoses.
Advantages.
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The computer can store far more information than a human. It can draw on a wide
variety of sources such as stored knowledge from books case studies to help in diagnosis
and advice.
The computer does not 'forget' or make mistakes.
Data can be kept up-to-date.
The expert system is always available 24 hours a day and will never 'retire'.
The system can be used at a distance over a network. So rural areas or even poorer
third world countries have access to experts.
Provides accurate predictions with probabilities of all possible problems with more
accurate advice.
Some people prefer the privacy of talking to a computer.
Limitations /Disadvantagesof expert systems
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Over reliance upon computers
Some ‘ experts’ could loose their jobs or not be given training if computers are available
to do the job.
Lacks the 'human touch'! – lack of personal contact
Dependent upon the correct information being given. If data or rules wrong the wrong
advice could be given.
Expert systems have no "common sense". They have no understanding of what they are
for, nor of what the limits of their applicability are, nor of how their recommendations fit
into a larger context. If MYCIN were told that a patient who has received a gunshot
wound is bleeding to death, the program would attempt to diagnose a bacterial cause for
the patient's symptoms.
Expert systems can make absurd errors, such as prescribing an obviously incorrect
dosage of a drug for a patient whose weight and age are accidentally swapped by the
clerk.
Shopping
Input devices
Output devices
Storage devices
Processes for automatic stock control
Benefits of automatic stock control
Benefits of e commerce
Disadvantages of using computer based shopping systems.
•Do not tell anyone your password
•Change password regularly
•Virus scan all discs
•Do not misuse the Internet e.g email, chat rooms
•No hacking
•Do not steal hardware / software
•Hacking
The Computer
Misuse Act 1990
•Blackmail using
•computer
•Spreading a virus
The Copyright
Act
Illegal to copy software
•Illegal copying : -software piracy
•Purchasing one legal copy and loading it
into several computers memory
•Downloading software over the Internet
creating a copy.
The Data
Protection Act
People were worried that;
Being asked for data which was
irrelevant to the purpose
e.g. What is your religion ?
Demand to see data and have it
corrected
Must have good security
passwords etc.
Justify and register why they
need that data
Length of time data was held on
computer about them
Get rid of any unused data when
finished with
Data given for on purpose e.g.
medical data was being sold on to
companies who produce mailing lists
for junk mail.
Not allowed to sell data on.
Data was wrong
Hacking into personal data
1. Personal data shall be kept up to date and accurate .
2. Personal data obtained lawfully only for one purposes must not used for another
3. The data must be relevant to the purpose for which it is given
4. Personal data shall not be kept for longer than is necessary
5. It should be kept secure against unauthorised access and loss
6. Personal data shall not be transferred to a country outside the EEC
Exemptions on data
1.
Personal data required by the Inland revenue
2.
Personal data used by national security or a
solicitor in a legal case
3.
Personal data kept by the user on himself or family
e.g. files on birthdays, addresses etc.