Zusammenfassung der Ressource
ICT GCSE -
Topic 1 :
Data,
Information,
Knowledge
- Evaluating
data for
fitness
for
purpose,
accuracy
and bias
- GIGO
- Abbreviation for
garbage in
garbage out. It
means if you
out rubbish in
the computer -
then you get
rubbish out.
- Data
- Raw
facts
and
figures
with no
meaning,
e.g.
readings
from
sensors
and
survey
facts,
etc.
Data
can be
numbers,
words,
images,
sound.
- Processing
- Data is
processed by a
computer.
Performing
calculations or
arranging the
data into a
meaningful order.
Eg. Working out
an athlete's
average age over
3 tears.
- Information
- Data that has
been been
processed by
the computer.
- Data + Meaning + Context = Information
- Knowledge
- Derived from information by
applying rules to it. Knowledge
is the application of
information to a situation.
- Example -
- 99 = Data,
£99 price of
tv =
information, I
only have
£90
therefore I
do not have
enough
money to
buy this tv
- Encoding
and the
storage of
data
- Encoding
- Assigning
codes to
the data,
reducing it's
size.
- E.g - Size
of clothes
- S =
Small, M =
Medium, L
= Large.
- E.g - Airport
codes - LHR
= London
Heathrow,
MAN =
Manchester.
- Advantages
- Takes up
less storage
space, easily
transferable,
easier to
back.
- Disadvantages
- Easily
stolen,
training
needed,
security
problems,
viruses
etc.
- Data Validation
- Transcription error
- Error made
when typing in
data using a
document as
the source of
the data. E.g -
Mishearing
what a person
says over the
phone and
entering it into
the computer.
- Presence Check
- Is used to check that data is entered is entered into the correct fields. E.g
- Entering your username and password into facebook.
- Transposition error
- Error
made
when
characters
are
swapped
around so
they are
in the
wrong
order. E.g
- putting
in
faceboko
instead of
facebook
- validation Checks
- Are checks a developer of a solution sets/ creates, using the software, in order to
restrict the data that a user can enter, so as to reduce errors. Presence and range
checks are validation check examples.
- Check digit
- A decimal
number (or an
alphanumeric
character) added
to a number for
the purpose of
detecting the
sorts of errors
that humans
normally make on
a data entry. E.g
- Account
numbers will have
check digits, to
check that the
numbers inputted
are correct.
- Range
check
- Data validation
technique which
checks that the
data input to a
computer is within
a certain range. E.g
- checking the data
of birth of a year 9
pupil is lower than
1998, since the
system wouldn't
allow that person to
enter that date as
they are too old for
year 9.
- Data verification
- Batch total
- A meaningful total
that is used to check
that the computer has
input all the data. E.g
- adding up all the
totals of a batch of
sold ebay items.
- Hatch total
- Meaningless total
of numbers, such
as order numbers,
used to check
that all the data
has been entered.
- Parity check
- Check to make sure that the data
sent is the same as that recieved
when data is transmitted from one
computer to another. E.g - An email
sent from one person to another.
- Verification
- Checking that the data
being entered into the
ICT system perfectly
matches the source of
the data. E.g - Checking
the text/ data in an
email and making sure
when it arrives to the
recipient that no error
has been introduced.