TA3: Data and testing

What you need to know

• The difference between data and information • What the relationship is between data and information.

Data is just facts and figures that have no meaning or links. When data is processed into information, it is given a meaning. Data Data is facts or figures that have no meaning or link. Information Information is where data is given some meaning, so that you understand what it is about. For example, a travel agent may have a list of airport codes for destinations where it has special offers. The codes are all 3 letters long. LIN is Milan Linate. Relationship formula To remember the relationship between data and information, use this formula: Information = data + [structure] + [context] The information might need to be in a specific format, like a postcode, which is why structure is sometimes needed. • Data is a list of items that have no meaning or structure. Remember it! 1 Define the term ‘information’. (2 marks) 2 Explain why some information Practise it! SAMPLE has a structure, using a • Information is where data has been given suitable example. (3 marks) some meaning. 3 Discuss the impact of selling information • Information = data + [structure] + [context]. about your customers. (9 marks)

Tip: This has a link to TA4 and the different legislation.

What you need to know

• The different data types and how they can be used • Which data type is suitable to use in a given context.

When data is stored, it uses a chosen data type. When applying a data type to a set of data, it is important to think about what the data is and how you are going to use it. Common data types Name Brief description Example Alphanumeric Combination of letters and numbers. Password1 Boolean Only has two responses. Yes Date/Time Stores a range of date and time formats. 24/12/2024 Text Stores any possible character. Password1P*£ Numeric Stores a number in a variety of ways. £20,000 Real, e.g. π Numeric Data Types Integer, e.g. –9786 Percentages, e.g. 67% Decimal, e.g. 8.9856 Currency, e.g. £5.99 • Numbers can be formatted as different numeric data types. • Alphanumeric only contains text Remember it! Jefferson is creating an ordering system for his furniture workshop. Complete the table to show which data types Jefferson should use Practise it! SAMPLE and justify your choice. and numbers.

Field Data type Justification • The Date data type also includes time.

Item name

Price

Collection date

(6 marks)

What you need to know

• What the purpose of validation and verification is • What tools verification uses.

Entering data into a system is useful. Validation and verification check that the data being entered is sensible and matches the original data entered. Validation This checks that the data entered is sensible, for example, a date is entered that is in the future rather than in the past. It also checks that it is reasonable, for example, an amount entered is £100 rather than £100 000. If the data entered does not meet either of these checks then an error message appears. It does not check that the data is correct. For example, if you are trying to reserve a table in a restaurant, you are only allowed to book a table in the future rather than in the past. Verification This checks that the data that is entered matches the original data. It does not check that the data is correct, for example, that a road name is spelt correctly in an address. It is often completed through double entry or by manually checking what has been entered. For example, when filling in an online form you might be asked to enter your email address twice. Double entry is a more common form of verification than manual checking as a computer is less likely to make mistakes comparing entries than a user. SAMPLE • Verification and validation tools don’t check that the data is correct. • Verification tools are double entry or manual checking.

Practise it!

1 Explain the term ‘validation’. (2 marks) 2 State one validation tool. (1 mark) 3 Explain how double entry is used as a verification tool. (2 marks)

Remember it!

What you need to know

• Validation tools • How each tool can reduce errors.

There are checks that can be made to validate data. Some of these have a specific role. Each validation tool helps reduce errors when entering data but it does not check the data is correct. Different validation tools Tool What is it checking? Example Data type check Is the data entered using the correct data type? A Boolean data type will not accept ‘X’. Format check Is the data entered in the expected format? If it is a date, does it look like dd/mm/yy? Input mask Is the data being entered in the expected way? Most postcodes look like LLNN NLL. Input masks help input the data into the correct format. Length check Is the data the expected minimum length? A mobile number is 11 digits long. A length check can have a set length or a minimum or maximum amount. Limited choice Is the data you want to enter on the list provided?

There might be a choice of drinks you can choose from. Lookup Is the data an accepted value? When inputting your postcode. Presence check Has the data been entered? Have you entered a date? Range check Is the data within a specific range? Is the date between 11/12/2022 and 11/12/2023? • There are three types of limited choice Remember it! Which validation tool would you use for: Practise it! SAMPLE (a) Entering a password that has to tools: drop down lists, radio buttons and be 11 characters long? (1 mark) tick lists. (b) Entering a hotel price in $? (1 mark) • Presence check is as it suggests – is the (c) Entering a car number plate? (1 mark) data there? (d) Picking a number between 1 and 10? (1 mark)

What you need to know

• Each method of collecting data • The advantages and disadvantages of each method.

Choose from the many ways in which you can collect data and information based on what is to be collected, where it is from and how you will process and store it. Primary methods are where you collect it yourself. Method Description Advantages Disadvantages Email Sending an interactive form or link to a survey. There could also be questions within the email itself. • No limit on the number of people. • Results collated automatically – low risk of human error. • Qualitative feedback. • Might be sent to wrong address or put in the junk folder. • Not everyone has an email address. • Emails might not be checked frequently. • Reliant on an internet connection. • Harder to analyse. Interview A dialogue between two people, asking open questions in person. • Questions answered more honestly between interviewer and interviewee. • Questions can be adapted and answers clarified. • Costs time and money. • Inconvenient for a large number of people. • Poor interview leads to poor questions. Online questionnaire and survey Specific set of open and/ or closed questions. • No limit on the number of people. • Simple to analyse. • Often cheap to conduct.

• Depends on internet access. • Inaccurate results if an unintended audience respond. • Results depend on welldesigned questions. • Primary data collection is where you Remember it! 1 Define the term ‘primary Practise it! SAMPLE data collection’. (2 marks) collect the data yourself. 2 Describe one advantage of conducting • Larger responses are received if you use primary research using email. (2 marks) email or an online survey. 3 Explain one disadvantage of conducting primary research using an interview. (2 marks)

What you need to know

• Each method of collecting data • The advantages and disadvantages of each method.

Data and information that has been already collected is known as secondary data.

Method Description Advantages Disadvantages Book Written by a specialist on a specific topic. • Author knows the topic. • References to the data being collected. • Might be out of date. • Author bias. Government statistics Data collected and analysed by the Government. • Large sample size. • Unbiased. • Not focused on a specific area. • Age of data. Magazine Published on a specific topic. • Author usually knowledgeable. • Data and information up to date. • Data and information could be presented in a biased manner. Website Published online about a specific topic. • Data updated quickly and frequently. • Simple and quick to search.

• Not clear how and by whom the data was collected. • Specialism of the author. It is important to remember that whenever you are using secondary research you need to consider the source of the information, as bias is going to be an influence. As well as bias, the location of the secondary data will also be an influence as this may be a global source rather than in the country you are in. • The sample size is often not clear or suitable. Remember it! 1 Define the term ‘secondary data collection’. (2 marks) Practise it! SAMPLE 2 Describe one advantage of • The age of the data should be considered. conducting secondary research using government statistics. (2 marks) 3 Explain one disadvantage of conducting secondary research using a website. (2 marks)

What you need to know

• Description of the Cloud and how it is used to store data • The advantages and disadvantages of using the Cloud.

What is the Cloud?

This is a general term for storage that can be remotely accessed through the internet. Location of the data is not important but rather that the data is stored on a server that is connected to the internet.

No limit on how much you can store. Accessed from any device with an internet connection.

Security is dealt with by the Data easily shared with other users

Cloud company. at the same time.

Advantages If you have access to your data from any location, then potentially so does a hacker.

Reliant on an internet connection. Cost of increasing storage limit. Owners of the servers have access to your data. Reliant on someone else’s security. Disadvantages SAMPLE

Practise it! Remember it!

1 Explain why relying on the internet is a disadvantage of Cloud storage. (3 marks) 2 A law firm uses Cloud storage for their client information. Give two benefits this has for the law firm. (4 marks) • Data is either stored logically or physically. • The Cloud relies on an internet connection.

What you need to know

• There are internal and external storage devices • The advantages and disadvantages of both locations.

Physical storage of data can occur either inside a device (internal storage) or outside of a device (external storage). Location Description Advantages Disadvantages Internal storage Method of storing data built into a device. • User has main control over access. • Easy to back up. • Easily damaged when moved. • Needs to be kept cool. • Noisy. External storage Method of storing data that is separate to a device. • All options are portable. • All options can be used as a back-up.

• Needs additional security. • Most reliant on a power source. When considering using internal or external storage, there is a range of considerations to think about. The main constraint will be the type of device you are using and how you use the device. Remember it!Practise it! SAMPLE • Security needs to be considered for both internal and external storage. • The environment the storage is kept in should also be considered.

A new shop is opening in town. The owners need to plan how they will store their customers’ data as they plan to operate a loyalty scheme. Discuss the options and make a recommendation. (9 marks)

What you need to know

• The different ways data can be stored internally • The advantages and disadvantages of internal storage devices.

These are devices which are generally kept in the same location and are the initial storage device a user will access. Type of drive Description Advantages Disadvantages Primary hard drive Storage that is built into a device; only the user of the device can access the data in order to create, edit or delete files. • Large storage amount. • Low cost. • Not reliant on any external connections for access. • Access to the data is limited to the users. • User responsible for security and back-ups. • Limited accessibility via the device. • Storage space not easily extended. • If the device breaks, the data could be irreplaceable. Network drive Storage accessed via a series of servers within the same location as the device. • Accessible from multiple devices within the same location. • Other users can access the same data. • Remote access is possible. • The company knows exactly where the data and information are stored.

• Users have limited access. • User responsible for security. • Both setting up and security can be costly. • Need to have specialist knowledge. • If security is weak then hackers can still access the data and information. It is a simple assumption that internal storage is physically within a device. However, the use of network drives ensures that the internal storage is available via remote access within the same location as the device. SAMPLE • Users are limited to the location of the device. • A network is a series of devices linked together, usually through a server.

Practise it!

Tim runs a small law office. He has a partner and a secretary. Which method of internal storage would suit Tim’s office? Justify your choice. (4 marks)

Remember it!

What you need to know

• The different ways data can be stored externally • The advantages and disadvantages of external storage devices.

These devices are much more portable and therefore can change location with ease. Some of these external storage devices are newer and are starting to become more commonplace. Type of drive Description Advantages Disadvantages Portable external hard disk drive (HDD) Storage similar to a primary hard drive. It has its own casing and is connected via USB. • Increases storage of connected device. • Useful as a back-up device. • Can improve performance of the main device. • Easy to damage with a low chance of recovering data. • Vulnerable to damage from natural sources such as heat, sunlight. • Not automatically secure. Portable solid-state drive (SSD) Storage similar to a portable hard drive. It has no moving parts. • Faster accessibility. • Lighter and therefore more convenient. • Robust and not as noisy. • Expensive. • Hard to restore data if it’s deleted or the device is damaged. • Not automatically secure. Networkattached storage (NAS) device Storage device connected to a network, usually in a central location for stored data. • Remote access. • Set user permissions for security. • Easy to set up and install. • Too many users can make it slow. • Specialist needed if there is a problem. • Stored in same location so off-site back-up needed. Portable USB flash drive Small device that connects via USB port. • Can be used with many devices. • User has control of security and back-up. • Provides remote access when used with internet. • Limited storage space. • Small in size so easy to lose. • Needs additional security adding. Portable wireless drive Connects via Bluetooth or Wi-Fi to most mobile devices. • Useful as a back-up. • Battery powered.

• Limited security. • Small, so easy to lose. Remember it!Practise it! SAMPLE 1 Explain two advantages of using an HDD to store data. (4 marks) 2 Give one reason why the owner of a smartphone might use a portable wireless drive instead of a USB flash drive to back up photos. (1 mark) • HDD and SDD devices operate in a similar way but HDD is a cheaper option. • Each device is limited by its storage size. • No additional security is in place on any of the devices. This is something the user has to add such as a password.

What you need to know

• The reasons for testing, and the advantages and disadvantages of testing • The types of data that can be used in a test, and why.

Products and solutions are tested to ensure that they meet the needs of the client or brief, and are fit for purpose, secure and safe. Testing is not just seeing if something works or not and should be considered during design.

Purpose of testing • To check that it works. • To check that the finished product meets the needs of the client/brief. Advantages Disadvantages • Saves time and money, especially if you test as you make it. • Confidence in the finished product. • Product will work as expected. • Allows you to find and solve problems as the product is created. • Takes time to test. • It can be costly to test a product. • Length of project needs to include testing time. • Testing needs to be planned. • Not all problems might be found in testing. Types of test data Type Description Example Invalid/Erroneous data Data that is incorrect and the product should reject automatically. If you are asked to input a date in the future but you add one from last week. Extreme data Data that is close to being correct but isn’t and should still be rejected. If you are asked to input a date in the future but you add today’s date. Valid data Data that is correct and should be accepted by the product.

If you are asked to input a date in the future and you add one for next month. Remember it!Practise it! SAMPLE

Amy has created a website for her new baking business. She doesn’t think she needs to test it as she used a pre-made template to create it.

Give two reasons why Amy should still test her website. (2 marks) • Testing is good practice for any product. • Testing should always be planned into the life span of any project. • When testing it is important that all three types of data are used as this will accurately test the product.

What you need to know

• What technical testing is • What happens in technical testing.

There are two ways a product can be tested: technically and by the user. Technical testing is where the product is tested to make sure there are no errors and it meets the specifications of the client brief. Need for technical testing • To check that the product works overall. • To check that the product meets the specifications from the client. • To test that each command works as expected. Examples of technical testing include: • Checking links and navigational elements on websites. • Checking that apps behave appropriately on different device formats. • Checking that macros in spreadsheets produce expected results. Advantages Disadvantages • Spots any errors early in development. • Helps measure progress. • Identifies any risks so a solution can be found.

• Takes time to test. • Problems can delay the project. Technical testing is done by a member of the team who is making the product. For example, it could be one of the software engineers who is creating the program. • Technical testing only focuses on the Remember it! Babu has created a website for his new Practise it! SAMPLE accounting business. technical elements of the project. In other (a) Give three examples of tests Babu words, does an element work? could use to test his homepage. (3 marks) (b) Explain one reason why Babu needs to have both technical and user testing for his website. (2 marks)

What you need to know

• What user testing is • What happens in user testing.

User testing is when the product is tested from the point of view of the final user. It is always important that the user tests a product. Need for user testing • To check the product from the viewpoint of the intended user. • To check that the product is user friendly. • To test that the user can complete necessary tasks. Examples of user testing include: • Asking users to find information within pages or sections of a website. • Ensuring users can navigate to specific information within a given number of clicks or swipes. • Asking users to rate the readability of text on small screen sizes. Advantages Disadvantages • User feedback helps develop a product. • No specific workspace is needed. • Can check how long it takes to complete specific tasks. • Can see how happy users are with the product.

• It takes time to test with a range of users and they will need to be paid. • Focus is on the quality of the product rather than the technical errors. When conducting user testing, it is important that you have a full range of potential users. For example, this could be based on age or interests. Ultimately it needs to be representative of your intended demographic. Remember it!Practise it! SAMPLE • More than one user is needed for user testing – you need a range of audiences. • User feedback has additional costs – paying for the time of the tester.

Mia has created an app for her new enterprise. Before she launches the app, her friend has suggested that she spend some time getting it user tested. Discuss the benefits user testing would have for Mia. (4 marks)