Data, Information, and Knowledge Overview

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Describe the difference between data and information.

Data usually refers to raw data/unprocessed data. Information is data that has been processed in such a way as to be meaningful. Information is data that has structure and context.

Tick four correct statements in the following table. There are different types of data.

True and false are examples of Boolean data (correct)
How many times a student has taken an exam would be stored as a Date/time data type
A field containing the value 253 would be a field containing text data
A real number is an integer which has already been used in a database
All numbers are stored as decimals
A percentage value is usually stored as text as it has a percentage sign
245.6 is an integer
'13cm' is an example of alphanumeric data (correct)
Currency is a type of numeric data (correct)
An integer stored in a field is a form of numeric value (correct)

Tick the correct statement regarding the coding of data. There are many ways of changing data to suit a purpose including coding, encoding and encryption of data.

An advantage of coding data is that codes are never complicated
A disadvantage of coding data is that it becomes much slower to type in the data
A disadvantage of coding data is that it makes the data very difficult to read and understand
An advantage of coding data is that it saves storage space (correct)

Tick the correct statement regarding the encryption of data. There are many ways of changing data to suit a purpose including coding, encoding and encryption of data.

Encryption is the conversion of data into a form that cannot be easily understood by unauthorised users (D) Signup and view all the answers

A shop selling Konia mobile (cell) phones keeps records of all the phones it sells. The shop only stocks three models but each model has either 32 or 64 GB of memory. An example of the shop's database is given below. Name this validation check and describe how it would work.

Lookup check. A table of the three models would be stored. Data is entered into a cell with the rule. Data is compared to entries in the table. If data matches an entry it is allowed/lf data entered does not match any of the entries in the table it is rejected. Signup and view all the answers

Giving examples, explain how consistency checks could be used to ensure that the data that is entered in the shop's database is valid. A shop selling Konia mobile (cell) phones keeps records of all the phones it sells. The shop only stocks three models but each model has either 32 or 64 GB of memory. An example of the shop's database is given below.

Rule could be that price must match model number. If the model number is 1273C3 price must be $300. If the model number is 1273C6 price must be $400. If the model number is 1275C3 price must be $350. If the model number is 1275C6 price must be $450. If the model number is 1278C3 price must be $500. If the model number is 1278C6 price must be $600. Rule could be that memory must match model number. If model number ends in 3 memory must be 32. If model number ends in 6 memory must be 64. Signup and view all the answers

Using another appropriate example, describe what is meant by static data. A newspaper story is regarded as static data.

Data that does not change. It can be read without being written back to a file/not changed when written back. Limited amount of information in a static information source, because as soon as it is created it is difficult to have information added to it, Static data tends to go out of date quickly. Appropriate example such as a CD ROM contains static data. Signup and view all the answers

Ashraf has used a word processor to type up an essay for his history assignment. He wishes to make sure that there are no errors in the text he has written. Describe how he could proofread his essay.

Read the text carefully to find/correct typographical errors/mistakes in grammar/style/spelling. Printing a copy is sometimes better than reading on screen, as it allows you to catch more visual errors. Read the essay out loud, as this will help you catch errors in grammar and sentence structure. Use a blank sheet of paper to cover up the lines below the one you are reading, to prevent you from skipping ahead of possible mistakes. Use the search function of the computer to find mistakes he is likely to make, such as 'it,' for instance, if he confuses 'its' and 'it's', 'there' for 'their' or 'they're'. Check separately for each kind of error he is likely to make, moving from the most to the least important. Read through once backwards, sentence by sentence. Read through again forward to be sure subjects and verbs agree. Signup and view all the answers

A school secretary has just been given some student data to enter into a school's database of student records. These include student numbers and dates of birth such as: 13542767, 14/07/2000 and 11987643, 13/10/2001. In order to ensure accuracy of the input, the data will be validated. Possible validation checks which could be used are range checks, check digits and format checks. Analyse the effectiveness of these checks in validating this data.

To be marked as a level of response: Level 3 (7-8 marks) Candidates will describe each check and give benefits and drawbacks of each check/consider different reasons for using each check. The issues raised will be justified. The information will be relevant, clear, organised and presented in a structured and coherent format. Specialist terms will be used accurately and appropriately. Level 2 (4-6 marks) Candidates will describe each check and give benefits and drawbacks of checks/consider different reasons for using each check although development of some of the points will be limited to benefits or drawbacks. For the most part the information will be relevant and presented in a structured and coherent format. Specialist terms will be used appropriately and for the most part correctly. Level 1 (1-3 marks) Candidates may only describe checks, and give basic reasons. Answers may be simplistic with little or no relevance. There will be little or no use of specialist terms. Level 0 Response with no valid content. Signup and view all the answers

A CD-ROM encyclopedia is considered to be a static information source whereas a website encyclopedia is considered to be a dynamic information source. Explain the differences between static and dynamic information sources.

Static information sources are carefully checked for accuracy, as once the data are used it is difficult to change. There is a limited amount of information in a static information source, as soon as it is created it is difficult to have information added to it. A dynamic data source can have information updated quite quickly. The data in a dynamic data source is usually up to date/static data tends to go out of date quickly. There can be many contributors to a dynamic data source such as a website, so the information can be inaccurate. Signup and view all the answers

A school marks all its exams out of 100. It has recently introduced a system of positive marking for students in years 12 and 13 whereby students will be awarded 10 marks for just sitting the exam and then, as normal, will be awarded further marks for correct answers. After the papers have been marked, the school secretary will enter the marks into a student database together with the year the student is in and their date of birth, which must be entered in the form dd/mm/yyyy. It is acceptable for data to be omitted for certain students. Apart from type check or length check, describe four different validation checks which should be carried out on the data to help prevent mistakes occurring.

Range check for the exam mark. No mark should be less than 10 or greater than 100. Lookup check for year. Years should match 12 or 13. Format check for date of birth. All dates of birth must be two digits followed by a slash followed by two digits followed by a slash followed by four digits. Consistency check on year with date of birth. The date of birth can be checked to see that the year the student is in corresponds to that. Signup and view all the answers

A health inspector, Josefine, is investigating the health of students. She wishes to study the effect on them of traffic on roads passing close to the school. One road seems to be causing more problems than others. She is going to collect data regarding the amount of traffic and its effect on their health. Describe, with specific reference to the investigation, how she could gather data from direct data sources.

She could give questionnaires to students who walk to school using that particular road asking about their general health/number of days missed through illness, She could give questionnaires to students who walk to school using other roads asking about their general health/number of days missed through illness. She could interview students who walk to school using that particular road asking about their general health/number of days missed through illness, She could interview students who walk to school using other roads asking about their general health/number of days missed through illness. She could observe/keep a count of traffic coming down the busy road, She could observe the amount of traffic/keep a count of traffic coming down the other roads. She could use sensors to detect the flow of traffic going down the busy road, She could use sensors to detect the flow of traffic going down the other roads. She could give questionnaires to residents who live in that particular road asking about their general health, She could give questionnaires to residents who live in other roads asking about their general health. She could interview residents who live in that particular road asking about their general health, She could interview residents who live in other roads asking about their general health. Signup and view all the answers

Describe the drawbacks of gathering data from direct data sources. A health inspector, Josefine, is investigating the health of students. She wishes to study the effect on them of traffic on roads passing close to the school. One road seems to be causing more problems than others. She is going to collect data regarding the amount of traffic and its effect on their health.

Data gathering may be expensive as other companies may have to be hired to get it. It may involve having to purchase equipment such as data loggers/computers/printers. Compared to indirect data sources using direct data sources may be very expensive in preparing and carrying out the gathering of data. Costs can be incurred in producing the paper for questionnaires, It takes longer to gather data than to acquire data from an indirect data source. By the time the project is complete/all the data is collected the data may be out of date. The sample size may be small. Signup and view all the answers

Give reasons why the information that Josefine collects may be inaccurate, A health inspector, Josefine, is investigating the health of students. She wishes to study the effect on them of traffic on roads passing close to the school. One road seems to be causing more problems than others. She is going to collect data regarding the amount of traffic and its effect on their health.

In questionnaires and interviews the questions may not have been very clear and the respondents may have misunderstood them, so that the respondent thought they knew the answer Josefine wanted - resulting in similar answers from different respondents. Questions may have been open-ended allowing the respondent to produce answers which could not be quantified. In a multi-choice type question there may not have been a sufficient number of alternatives. The respondents selected for the study may not have been very representative. There is the possibility that Josefine may have made errors when collecting it. Josefine may have made errors when entering the collected data into the computer. If the data was collected automatically by sensors the computer/microprocessor may not have been set up properly to accurately interpret the readings. Signup and view all the answers

Give three reasons why the teacher is planning to code the data. The school's students have collected data about cars for a maths project. The teacher has decided to code the data. Here is some of the data. The codes he will use are in brackets.

Speeds up data entry. Accuracy of entering data is increased. When data has been coded it makes it easier to use validation. Less storage space is required. The smaller the size of the database, the faster it will be to search and produce results. Signup and view all the answers

Give three reasons why the IT teacher has warned against some of the coding the maths teacher plans to use. The school's students have collected data about cars for a maths project. The teacher has decided to code the data. Here is some of the data. The codes he will use are in brackets.

The code B does not give a clear idea of what shade of blue. The approximate age of the driver is too vague/too general and would be difficult to use in calculations/graphs. There may be many makes of car beginning with the same letter. Signup and view all the answers

Lan wants to apply encryption to all his emails. He is not sure whether to use asymmetric or symmetric encryption. Describe what is meant by the asymmetric method of encryption.

Asymmetric encryption is often referred to as public key encryption, The public key is used to encrypt the data while, the corresponding private/secret key is used to decrypt the data. The public key is published to everyone, but the private key is kept secret. Anyone with a copy of the public key can encrypt information, but only the private key holder can read it. It is not possible to deduce the private key from the public key. Signup and view all the answers

Tick the four most accurate statements regarding the quality of information.

Irrelevant information leads to poor quality information (A), The more complete the collected information is, the better its quality (E), A great deal of detail can sometimes lead to poor quality information (I), The accuracy of the information collected affects its quality (J) Signup and view all the answers

Tick the four statements which most accurately refer to encryption.

Encrypting a hard disk prevents viruses from deleting the information (C), The recipient can only decrypt the message with the key provided by the originator (D), Encryption is the scrambling of the text in a message (I), Encryption is the process of encoding messages in such a way that only authorised parties can understand them (J) Signup and view all the answers

A school secretary has been handed some data by a student: Prasad, Anoushka, SR132516, 52, 01/09/2000. Explain why they are regarded as just items of data. In your explanation give a possible context for the data and describe how this would make the data become information.

They are just a collection of text, numbers and symbols with no meaning. A possible context is that the data is about the student and represents: their family name, first name, student id, their latest maths mark and their date of birth. Signup and view all the answers

Atat Iron Ltd uses computers to process its payroll. The company pays its workers weekly which involves the updating of a master file. Two sets of data are shown below. The first set represents part of a transaction file containing workers' ID numbers and the hours worked by those workers in a particular week. The second set represents part of the master file used by the company. This shows the workers' ID numbers, departments they work in and the rate per hour at which they are paid in Indian Rupees(2). Without using a type check, describe three other validation checks you would develop to make sure all the data entered is sensible.

Length check on Workers ID number. Must be exactly 6 characters long. Lookup check on Department. Must be one of Foundry, Cold rolling, Tube production, Extrusion or Hot rolling. Range check on hourly rate. E.g. be between 50 and 65. Signup and view all the answers

Tick the four most accurate statements referring to the meaning of data and information.

Data consists of raw facts and figures (E), Data is a collection of text, numbers, symbols, images or sound (F), Knowing that 159.5, 164.3, 162.9 and 172.3 are the heights in centimetres of pupils in a school makes it a set of data (G), Data must have a context to become information (H) Signup and view all the answers

Tick the four most accurate statements referring to dynamic and static data.

Data on a web page that is updated from time to time is an example of dynamic data (C), Data that is read from and not written back to a file is called static data (D), There can be many contributors to a dynamic data source so the information can be inaccurate (G), It is very difficult to add information to a static information source after it has been created (H) Signup and view all the answers

The secretary of a company is transferring workers' records from paper to a new computer database. She wishes to make sure the data in the database is accurate. To check the data she is using verification and validation. Using an example, or otherwise, explain why she is using validation as well as verification.

Verification is checking that data that has been/is being entered into a computer has been copied correctly from the data source. Validation is checking that the data entered is reasonable/sensible. Neither method checks that data is accurate/correct. Although verification helps to stop users from making mistakes when entering data it cannot check that the data was originally correct. Validation is needed because although the data might be copied correctly, the original data might be invalid. The date of birth might be in the form dd/mm/yyyy and the data might have been correctly copied as 1994/12/31 but this is not in the correct format, a format check would have picked this up. Common errors when copying data are transcription and transposition errors. Verification would pick up a transposition error but most validation checks (except a check digit) would not. Verification would pick up transcription errors but validation might not. Signup and view all the answers

When data is entered into a database it needs to be checked for accuracy. One of the methods used to help in this process is verification. Compare and contrast the different methods used to carry out verification.

Both involve checking that data has been entered correctly not that it is correct. Visual verification is visually checking the entered data against the source document. Double data entry is usually two people entering the data/entered (by the same person) twice (and each version compared against the other). Visual verification is carried out by a human/user/yourself. Double data entry - verification is carried out by the computer. Visual verification will enable the user to see mistakes if they have been made, while double data entry the computer will alert user to the fact that a mistake has been made and they decide which version has been copied correctly. Signup and view all the answers

Jasmine is carrying out a study of the effect of pollution on her local countryside. She intends to use data from direct data sources as well as indirect data sources. Describe what is meant by direct and indirect data sources using examples from this scenario.

A direct data source is a source where data is collected for a specific purpose or task. Examples of direct data sources are questionnaires or data logging. An indirect data source is when data is obtained from a third party not necessarily related to the current task. Direct data source. It gives us data that is often called 'original source data'. Questionnaires could be distributed amongst farmers and local people asking about the effects of pollution. Interviews could be carried out with farmers and local people asking about the effects of pollution. Indirect data source. Means data that was collected for a particular reason but is then used for another purpose. Could collect data from local government agencies which may have pollution data for the local area. Could collect data from local environment groups. Signup and view all the answers

Encoding of data can be thought of as applying a code such as letters, symbols and numbers to data for conversion into a cipher. It can also be thought of as a form of analogue to digital conversion such as used by codec software. At times it is the term applied to the coding of data. Evaluate the need for encoding data and analyse the different methods that can be used to encode data.

This question to be marked as levels of response: Level 3 (7-8 marks) Candidates will discuss the importance of encoding data including the advantages and disadvantages. Candidates will explain the effectiveness of the main methods of coding in detail. The information will be relevant, clear, organised and presented in a structured and coherent format. There may be a reasoned conclusion/opinion. Specialist terms will be used correctly and appropriately. Level 2 (4-6 marks) Candidates will discuss the advantages and disadvantages of encoding data. Candidates will describe the main methods of encoding in detail. For the most part, the information will be relevant and presented in a structured and coherent format. There may be a conclusion/opinion. Specialist terms will be used appropriately and for the most part correctly. Level 1 (1-3 marks) Candidates will present advantages or disadvantages of encoding data. Candidates will describe at least one method of encoding in detail. There will be little or no use of specialist terms. Level 0 (0 marks) Response with no valid content. Signup and view all the answers

What is data?

Data is raw, unprocessed facts and figures, like numbers, words, symbols, and images.

Define information.

Information is processed data that gives context and meaning. It answers questions like 'who', 'what', 'when', 'where', and 'why'.

Explain knowledge.

Knowledge is the understanding and application of information. It's how we learn and make sense of the world.

What is data processing?

Processing transforms raw data into meaningful information. It involves operations like sorting, calculating, and analyzing data.