Transcript Information Revision - Computing and ICT in a Nutshell

Information Revision
• What we mean by data, information and
knowledge
• How data are captured
• The quality of data
• Problems with encoding
• The cost of keeping information up-todate
Information and Data
• Data are (i.e. data is plural) recorded:
– Facts
– Events
– Measurements
– Transactions
• Information has:
– Meaning…
– And the meaning is derived from the context or
processing applied to the data
Knowledge
• Every day we use our experience or understanding of
the way things work to interpret and act upon data and
information
• This experience is known as knowledge
• Our knowledge enables us to form a set of rules to
determine or predict what happens under different
circumstances
• For example:
– IF you forget someone’s birthday THEN they will get
upset
– IF the sky is dark AND you need to go outside THEN it
would be best to take an umbrella
Access to Knowledge
• Because computers are good at following rules (i.e.
programs), knowledge can be replicated by
computer systems
• These are called knowledge bases or sometimes
expert systems
• These are often used for medical or fault diagnosis,
but can only suggest probably (rather than certain)
causes, e.g.
– The NHS Direct Self Help Guide
– Windows Troubleshooting
Quality of Information
Good quality information is:
• Accurate
• Up-to-date
• Timely
• In the right level of detail
• Appropriately presented
Channels of information flow
Formal Channels:
Informal Channels
• Memos/letters and
group e-mails
• Ad-hoc meetings
• Formal meetings
• Intranets
• Conversations
• Rumours
• Individual e-mails
• Notice boards
• Reports
Which is most reliable?
Information Sources
• Organisations can develop their own information from data
generated in the course of day to day business
transactions - sales figures, production statistics and so
on.
• This would be described as internal data from a primary
source.
• The Office for National Statistics and companies such as
Dunn and Bradstreet can also provide specialist business
data
• It is highly refined and organised and is presented in a
manner appropriate to the client organisation.
• This would be described as external data from a
secondary source
Cost
• Producing and refining data into information is an
expensive business
• The more frequently the information changes, the
more expensive it will be to maintain it
• What are cost and technical issues associated with
obtaining information at different frequencies?
– What sort of organisation would require realtime or pseudo real-time processing?
– Who could use the less costly batch processing
method?
Nature of Information
• Some information is quantitative - sales figures,
passenger numbers or stock levels.
• Information can also be qualitative…
• For example, house buyers, house builders,
furniture retailers and financial institutions
depend on the predictions of organisations such
as Institute of Chartered Surveyors or Halifax plc.
in to the state of the housing market
• Clearly these are predictions rather than facts as
no-one can say for sure what will happen
Gathering Information
• It’s not possible to survey every member of a
particular target group (i.e. the people affected by the
issue)
• It is there necessary to sample data - this means to
select a representative section of that group.
• What would be a representative sample? One in a
hundred people? A thousand people?
• What if ask one in every hundred people outside
HMV in Cheltenham on a Thursday afternoon
between 2.45 and 3.45 p.m. what they thought about
pension? Would this be a representative sample?
Sampling
• Imagine that you are in charge of organising and
managing a mass market research survey to find out
purchasing habits of 25 to 30 year olds. You have
the following issues to consider:
– Where should the survey take place and when?
– How many people should we ask?
– How many people do I need to employ to carry out the
research?
– If we were to survey every 25 to 30 year old in the UK
what would the cost implication be, could we process
that amount of data?
Encoding
• Encoding is the process of storing the
information gathered in a form suitable for
processing on a computer.
• Would you just ask the 25-30 year-old What do
you spend your money on?
• How many different answers do you think you’d
get?
• What would be a more sensible approach?
Would it have any drawbacks?
Another Example!
•
How would an information manager predict national Christmas tree
sales for next Christmas to assist a UK importer manage demand?
– by focussing upon Christmas tree sales last year?
– using information processed by a new Internet based information
services company located in Austria?
– by using data related to the North West of England?
•
And what would he or she do with the information?
– pass it to the company's Finance Manager?
– ... on a Tuesday in mid-December?
– Summarised on the back a picture postcard of the Munich
Bierkellar?
– ...via the company's Catering Manager?
– ... in German?
Examiners’ Report
•
Students have been asked about the differences between data,
information and knowledge on many occasions. Unfortunately, many
candidates did not get high marks, mainly for the following reasons.
– they did not give definitions or examples that recognised that data
is plural (so that the use of a single number as an example of data
cannot gain credit)
– they did not give examples in an ICT context.
– for knowledge, they gave examples which were based on the traffic
light scenario i.e. knowledge means you know that if the light is
green you can go through the traffic lights.
– few candidates could define knowledge in an ICT context. Some
candidates defined it simply as: a set of rules, but did not say that
these rules are applied to information. A good definition would be
• Knowledge is a set of rules and concepts that can be applied to
information to gain understanding.
Examiners’ Report
• The data definitions were particularly well expressed, although
many of the examples of data were given single values such as a
telephone number or a date of birth. In some cases, no example
was given at all.
• Information was sometimes described as, “data that was labelled to
give it meaning.” These answers were unacceptable, as were
examples that showed labelling.
• Answers must show an appreciation that data is processed in some
way using ICT to provide information.
• Candidates seemed to find part describing knowledge difficult, and
described it as the interpretation of information, rather than what
allows people to interpret information and its use when making
decisions. Many candidates defined it simply as a set of rules.
• Examples frequently had no relevance to ICT.