Information Technology 9626/13 October/November 2024: question paper and mark scheme

Mark scheme

1 EIGHT from: 8 1 mark for each correct symbol (1st mark) (max 4) 1 mark for each correct matching purpose stated (max 4) Taken from syllabus: Purpose Symbol

Mark scheme

2 SIX from, e.g.: 6 • MIS is a computer-based system that provides managers with the tools to organise/evaluate/efficiently manage departments within an organisation (1) • It provides past, present and prediction information (answer must include TWO from) (1) • It is software based (1) • It includes a database/databases (1) • It includes a number of decision support systems (1) • It can be used to produce reports (1) • Can produce graphs/charts (1)

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3(a) TWO from: 2 • A database is in 1NF (accept list of 1NF principles) (1) • All the non-key attributes depend entirely on the primary key/it has no partial dependencies. (1) 3(b) EIGHT from, e.g.: 8 Benefits MAX 6 • Atomised data is easier to search on specific criteria (1) • Any change to one record which is needed can instantly be made to any related records//data editing is straightforward (1) • The database does not have redundant data (1) • File size is small/less storage needed (1) • There is no data duplication (1st) – so there are fewer errors in the data (1) – so there is less chance of storing incorrect copies of the data (1) Drawbacks MAX 6 • It can take longer to set up the database (1) • It is a more complex database (1st) • due to the relationships between tables (1) • Making data atomic may not always be the best solution (1ST) • such as (E.G.) date of birth can be separated into day, month and year but this may serve no purpose • Has more/multiple tables (1) • therefore setting up queries/reports/input forms can become more difficult (1) • making it difficult to keep track of data (1) • May require greater expertise (which may need to be bought in) (1).

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4(a) THREE from: 3 • Verification is checking that data that has been/is being entered into a computer has been copied correctly (1). • Validation is checking that the data entered is reasonable/sensible/valid/follows a set of rules. (1) • Verification will not pick up the fact that the original data might be incorrect. (1) • Validation can not tell if the data has been entered incorrectly (1) • Verification would pick up a transposition error. (1) • Verification would pick up a transcription error. (1) 4(b)(i) TWO from: 2 • It is a validation method (1) • It checks that data is possible/sensible for the context (1) • It checks that data is between an upper and lower acceptable value (1) • Sensible example (1) 4(b)(ii) TWO from: 2 • It is a verification method (1) • It is used to avoid/pick up transcription errors (1) • Two versions of the data are entered and compared (1st) – If a discrepancy between the two versions is found, user will be alerted (1) • Sensible example (1)

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5 FOUR from: 4 • The public key is used to encrypt the data (1) • The private key is used to decrypt the data (1) • The private key is sent separately to the receiver (1) • The private key is kept secret (1) • Anyone with a copy of the public key can encrypt information (1) • Only the private key holder can decrypt the information (1) • It is not possible to decrypt the data from the public key (1)

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6 THREE from: 3 • It will check the contents of cell B6 (any awareness that outcome is based on contents of B6) (1) • If the contents are NOT less than 5 (1) OR NOT greater than 8 (1) (accept converse) – ONLY award following if both above stated (NB note effect if answer above is converse) – The cell displays 4th Quarter (1) – if not/otherwise the cell displays a null string. (1) (Answer is dependant) OR • If condition not met, a blank cell is displayed (1)

Mark scheme

7 FOUR from: 4 • It is used in backward chaining (1) • It starts with a goal/set of goals (1st) – which establish the rules to be followed (1) – to identify initial conditions (1) • Inference engine uses the rules base (1) – to find one which has a THEN part that matches a required goal (1) (Award once only) • Inference engine explores the rules (1st) – until it finds one which has a THEN part that matches a required goal (1) (Award once only) • If the IF part of that rule is known to be true (1st) – it is added to the list of goals. (1)

Mark scheme

8 EIGHT from, e.g.: 8 Award ANY description of differing access to Information Technology leading to digital divide. ONE mark per description e.g. • Access to fast broadband can be better for those people living in urban areas than for those living in rural areas (1) • The quality of connection to the internet may be poorer in underdeveloped countries (1) • Buying televisions/personal computers/smartphones can be more expensive in rural areas (1) • Richer people are more/poorer people less able to afford the latest versions of televisions/personal computers/smartphones computers (1) • Lower paid workers may not be able to afford the hardware to be able to access the IT (1) • Uneducated people are often not aware of IT/importance of IT/benefits of IT/possibilities of IT (1) • Young people have grown up with the technology/older people may feel they are too old/unwilling to learn about new technology (1) • Disabilities of some users may inhibit the use of smartphones/computers. (1)

Mark scheme

9(a) FOUR from: 4 • Spyware is software that is installed/operates on a computer without the user’s knowledge (1st) – often the first indication is a noticeable reduction in processor speeds. (1) • Records/tracks what a user does on their computer (1) • Can gather information like e.g. web browsing habits (1) • Can capture email messages//a user’s personal data/information (can exemplify) (1) • Transmits this data to a third party over the internet (1) 9(b) FOUR from: 4 • A program (1) that replicates itself (1st) – until it fills all of the storage space (on a drive or network) (1) • It searches for more computers (1) • Exploits security holes in networks (1) • Worms can slow down a network (1st) – by consuming bandwidth (1) • Worms often originate from email attachments (1) • Worms then spread to a user’s contacts via their email account/address book. (1)

Mark scheme

10 EIGHT Marks available: 8 Definition of online processing: ONE from: • User is in direct connection with a central computer (1) • A real time relationship between user and seller via the internet (1) Max EIGHT: • Give a positive impact (1st) • Give an extension that is a positive implication on a customer or business of the identified justification. (1) e.g. • Speeds up the process of an individual order (1st) results in better customer satisfaction (1) Other areas of focus • Speeds up the process of a large number of orders • Allows online purchases • Allows online financial transactions • Helps to keep track of your stock levels • Continues to collect data, therefore more accurate • Reduces the time between ordering and delivery • Automated reordering • Integration with other online systems.

Mark scheme

11 FOUR from: 4 • Calibration improves the accuracy of sensors after they have become inaccurate (1) • Can correct the sensor so original reading is accurate (1) • (OR) can apply an offset to take account of an inaccurate reading (1) • Only one measurement point is needed (1) • Appropriate for sensors that have to measure a single type of value/variable (1) • Does not need to be calibrated against any other range of parameters (1) • Often needed for sensors being used at extreme values (1) • Reading is taken (from the sensor) and compared with a known value (1st) – in the range being measured (1) • Sensor reading is subtracted from the known value (1st) – which gives the offset (1) • The algorithm uses the offset by adding it to every reading in the parameter range being measured. (1)