3.1.1 Data, information and processing

3 disadvantages of original source data?

-Data gathering may take a long time to collect. -Data gathering may be expensive as you hire other companies to get it for you. -It may involve having to purchase equipment such as data loggers and computers.

3 methods of verification?

-Entering the data twice and making sure they are the same. -Checking the data against the original paper document as it is inputted. -Printing out the data and comparing to the original paper document.

2 advantages of archived data?

-Even though data is no longer being used, there is a permanent copy available just in case it is ever needed. -Expensive computer storage is released as unused data is removed from the system.

2 disadvantages of archived data?

-If archived data is needed in a hurry it has to be located, fetched and re-loaded back onto the computer system. -If there was a theft or fire, archived data might be lost. There might not be another copy.

3 disadvantages of static information source?

-If held on a CD, the disk could be lost or damaged. -If a mistake is found in the information then new copies need to be printed and distributed. -Can take a long time to produce i.e. in terms of checking, publishing and distribution.

3 disadvantages of using video to convey information?

-If viewing online then need a fast connection and plenty of bandwidth. -Need equipment e.g. computer, in order to view the video. -May become out of date and will cost to replace. (offline)

3 advantages of using LEDs to convey information?

-LEDs light up very quickly. -LEDs are very cheap and very long lasting. -Can display text in a wide range of colours and character heights which can help people with visual impairments (on display boards).

3 disadvantages of using sound to convey information?

-Need to be able to understand the language in order to understand what is being said. -People with poor hearing might not be able to hear the sound or instructions. -Some public speaker systems are muffled and difficult to understand.

3 disadvantages of using LEDs to convey information?

-Only able to impart limited information. -No use for people with visual impairment. -Difficult to see if bright background light or if positioned at the wrong angle.

3 advantages of using pictures to convey information?

-People understand images no matter which language they speak. -Can communicate ideas and concepts which might be difficult to do with text alone. -Convey information very quickly.

3 reasons why we code data?

-Speeds up data entry, e.g. faster to type 'F' than 'Female' -Increases accuracy of data e.g. avoids the risk of typing 'Femail' if 'F' is used. -Less storage space required as 'F' only uses one byte of data.

3 advantages of indirect source data?

-Takes less time to gather than original (direct) data. -Makes extra use of original data you already have by processing for a different purpose. -It may be cheaper to obtain than gathering original data.

3 advantages of static information source?

-Usually checked for accuracy so often more reliable than dynamic sources. -If the information is paper-based then it can be used without access to a computer. -Have a historical copy to refer back to even if a later version is produced. Whereas with a dynamic source, the data can be overwritten or vanish.

3 advantages of original source data?

-You get the exact data you need. -You only gather as much or as little as you need. -You know exactly where the data came from and so you can estimate how reliable it is.

3 advantages of archiving?

-You have a permanent record or source of the data/files that are no longer in use. -Reduces data which is stored on the network or system thus making it faster to back-up. -Network storage space is expensive. By archiving data it frees up space for data or files which are currently in use.

Example of Data

51,77,58,82,64,70 chocolate, strawberry, vanilla, strawberry, vanilla, vanilla, strawberry, vanilla, vanilla.

Real

A 'Real' data type is numerical data which contains decimal numbers, it would be used when extra detail is required and a whole number would not provide enough information.

Presence Check

A presence check makes sure that a critical field cannot be left blank, it must be filled in. If someone tries to leave the field blank then an error message will appear and you won't be able to progress to another record or save any other data which you have entered, e.g. your first/ second name.

Range Check

A range check is commonly used when you are working with data which consists of numbers, currency or dates/times. A range check allows you to set suitable boundaries, like lower and higher boundaries.

Factors affecting the quality of information?

Accuracy, Level of Detail, Completeness, Age, Relevance, Presentation.

Archived Data

Archived data is not immediately available online. It has been copied, then removed from the system and stored safely offline.

Archiving

Archiving is the term used to refer to making a copy of data or files which are no longer in use, removing the files from the network or system and then storing the files away from the computer, ready to be accessed at a later date if required.

Full Back-up

Backing up the whole system- the 'ultimate' protection against data loss as any of the tapes can provide the ability to restore the system very quickly at any point in time. This is probably not the most efficient back-up strategy because if files haven't been changed then you will be copying the same files that you did yesterday and the week before, even the month before, and a thief would have access to all the company data.

Boolean

Boolean data holds one of two values, for example yes/no. A boolean data type is used to answer questions where there are exactly two options, three options would mean it was no longer boolean data.

Input

Entering data into a system e.g. with a keyboard typing in data. Input data could be the grades of students from homeworks.

Level of Detail

For information to be useful you need the right amount of detail- there is a risk of having too much detail which makes the information overwhelming and difficult to extract the bits that you want to know about- there might not be enough detail in which case you won't understand the full picture. This links closely to one of the factors we covered earlier, 'completeness', e.g. telling you to use flour but not saying how much.

Information

INFORMATION = DATA + CONTEXT + MEANING OR Information is data which has been processed within a context and structure in order to give it meaning.

Relevance

In order for information to be useful it must be relevant to you, e.g. Whilst it might be interesting to find out what the weather is like in Florida or Melbourne today, it isn't really relevant to your everyday life. It won't help you decide whether you need to take an umbrella with you.

Completeness

In order for information to be useful it needs to be complete. If parts of the information is missing then you will not be able to make use of it or make accurate decisions, e.g. if you check the weather forecast and you are only told what the weather in the morning will be like. There is nothing about the afternoon.

Age

In order to be useful, information needs to be up-to-date. In many cases information changes over time and so old or out-of-date information can be misleading or give you the wrong picture of what is happening.

Presentation

Information which is presented in a disorganised way or in a manner that is hard to understand will be less useful to you and be of little value. Choosing the best method of presenting your information and perhaps sorting or organising it before you present it can make it much easier to understand and far more useful.

Software Costs

Initial purchases of the software (e.g. OS, utility and application software), then upgrading it, owning the licence, and technical support all add to the cost.

Knowledge

Knowledge is the capability of understanding the relationship between pieces of information and what to actually do with the information. What this means in simple terms is that you apply rules to the processed information e.g.: The shop manager can see that vanilla is the most popular ice-cream flavour. Next time he places an order, he will ask for five times as much vanilla ice-cream than chocolate ice-cream.

Back-up

Making a copy of your data is called a 'back-up'. The only way to ensure that you will always have access to a copy of your files is to make a copy of your work, preferably onto a removable storage device. This enables you to keep the copy in a different place to your hard disk - just in case there was a burglary or damage such as fire or floods, or the data became corrupted.

Static Information Source

Once a static information source has been created, it is unlikely to be changed or updated for a significant amount of time, e.g. an encyclopedia which has been produced on a CD-ROM. Once the encyclopedia has been written and checked for accuracy it probably will not be updated again for at least a year.

Coding data

One method of storing data is to assign codes to it. This usually means shortening the original data either by removing a few letters.

Hardware Costs

Original costs of the hardware, replacing it if it breaks, maintenance to check and repair it and storage of backups of the information add to the cost.

Feedback

Output from a system is fed back to the system to influence the input- e.g. when the ATM tells you that you can't withdraw the amount you entered as you don't have enough money in.

Validation

Reduces the number of errors in the data being entered into your system, by aiming to make sure that data is sensible, reasonable, complete and within acceptable boundaries.

Picture/ Format Check

Some types of data will always consist of the same pattern- e.g. a postcode. The majority of postcodes look something like CV36 7T. Replace with L for any letter which appears and N for any number that appears and you will end up with LLNN NLL. This means that you can set up a picture/format check for something like a postcode field to ensure that a letter isn't entered where a number should be or a number in place of a letter.

Length Check

Sometimes you may have a set of data which always has the same number of characters, e.g. a UK landline telephone number has 11 characters. A length check could be set up to ensure that exactly 11 numbers are entered into the field. This type of validation cannot check that the 11 numbers are correct but it can ensure that 10 or 12 numbers aren't entered.

Processing

Stage where data is manipulated to produce meaningful information, including sorting/ searching/ graphing/ calculating, e.g. searching sales data to find which products have sold the most.

Output

Stage where information obtained via processing is presented to the user in a suitable format, e.g. showing the weather forecast using graphics.

Manpower Costs

The cost of labour in terms of wages, and training new staff (paying trainers and lost time due to training) add to the cost.

Consumable Costs

The cost of paper, toners and cartridges are known as 'consumables' and all count towards the costs of producing information.

Stages example

The teacher takes a register each morning to see who is in the classroom (INPUT). The data is loaded into the school database and PROCESSED to create an attendance record for each pupil. The data is STORED for use at a later date for student reports. A printed list of all students who are absent is printed out (OUTPUT). A secretary might telephone parents to find out why students are not in school. This data is entered into the system to update the records (FEEDBACK).

Type Check

When you begin to set up your new system you will choose the most appropriate data type for each field. A type check will ensure that the correct type of data is entered into that field, e.g. no 'ten' allowed if it is meant to be '10'.

Lookup

Where you have a field which only allows a limited list of items to be entered then a lookup list can help to reduce errors. For instance, a look up list being used in a spreadsheet that only allows 8,10,11 or 12 to be entered, speeding up data entry and accuracy.

Incremental Back-up

With the method of making incremental back-ups, a full back-up of the system is made initially. Then each night, only the files which have been changed since the last incremental back-up are copied. Software is used to identify which files have changed. An incremental system of backing-up is much faster than making full back-ups. However, if the system should need to be restored it would take much longer than restoring from a full back-up.

4 costs of producing information?

-Hardware. -Software. -Consumables. -Manpower.

3 advantages of using text to convey information?

-Text based information is usually easy to understand. -Most people are familiar and comfortable with reading text. -A large amount of information and detail can be conveyed with text.

Integer

An Integer data type stores whole numbers, the numbers can be both positive or negative but they cannot contain decimal points or fractions. No text/characters/symbols.

Original Source Data

Original source data is where you have made efforts to obtain the data directly, e.g. with questionnaires/ face to face interviews/ observations.

Transcription Error

Person misreads what is written on the source document or perhaps mis-hears what the customer tells them over the telephone. It might simply be down to the person rushing and not being careful over which keys they press- e.g. typing Smyth not Smith.

Dynamic Information Source

'Dynamic' is characterised by continuous change, This is a fairly accurate description in terms of a 'dynamic information source', a good example of a dynamic information source would be a web site which is updated on a regular basis. Think about the BBC news web site - it is changed throughout the day as news stories happen around the world.

3 disadvantages of indirect source data?

-You may not know exactly where the data came from and so it may be unreliable. -There may be only a small part of the data needed so you have to extract what you want from a large data set. -You may not be able to obtain exactly the data you want.

Date/Time

A date / time data type is used to store any data that is related to date or time, however there are so many ways of showing it, and some countries have a different way of representing a date. For example 9/4/94 in the USA means 4th Sept 94.

Text/ String

A text or string data type can hold any alphanumeric character including text, numbers and symbols, the data can be pure text or a combination of text, numbers and symbols.

Sizes of Media

CD-RW- 650mb DVD-RW- 4.7Gb Flash memory- 16Gb Magnetic tape- 100Gb External hard drive- 1000Gb Online- Unlimited Gb

Data

Consists of raw facts and figures - it does not have any meaning until it is processed and given a context.

Accuracy

If the data that you have collected is inaccurate then the information it will produce will inevitably also be inaccurate, e.g. Questions might be poorly worded so that users misunderstand them.

Indirect Source Data

Indirect sources means data has been collected for a particular reason but then that data is used for something else, but not all indirect data is purchased from someone else. Data that has already been processed for a particular use might be re-used for another purpose (by-product of processing).

Storage

Information needs to be stored for use at a later date at any stage of the process (e.g. before any processing has taken place, or before outputting but after processing, or at the output stage like a film on a DVD).

Check Digit

This is used when you want to be sure that a range of numbers has been entered correctly. There are many different schemes (algorithms) for creating check digits. For example, the ISBN-10 numbering system for books makes use of 'Modulo-11' division. In modulo division, the answer is the remainder of the division.

Transposition Error

Transposition errors occur where the person entering the data accidentally changes the order of numbers or letters, e.g. typing 89 not 98.

Verification

Verification means to check that the data on the original source document is identical to the data that you have entered into the system or object document.

Difference between archiving and backing up?

When files are backed up, the original data still remains on the system. Whereas with archiving, once a copy has been made, the original files are removed from the system.

3 advantages of using sound to convey information?

-Can convey information and warnings very quickly e.g. a fire bell. -Don't need to actually see the person or source of sound to hear it. -Conveys lots of information fairly quickly.

3 disadvantages of using text to convey information?

-A large amount of text can be difficult to read and process at speed e.g. when driving. -If you are from another country and don't understand the language then you won't be able to read the text. -Blind or visually impaired people might not be able to access the information.

3 advantages of using video to convey information?

-A lot of information can be conveyed in a very short time. -Can be stopped, started, replayed over and over. -Information is accessible to people with poor literacy skills.

3 disadvantages of using pictures to convey information?

-Blind or visually impaired people might not be able to access the information. -If you don't know what the image means then it can't convey the information effectively to you. -Poor quality/fuzzy images might be hard to see or lose their impact.

3 disadvantages of using animation to convey information?

-Can be expensive and time-consuming to produce. -Can produce large file sizes which take up a lot of hard disk space or can be slow to download. - Animation when used alone might not convey the information. It may need sound or text support.

3 advantages of dynamic information source?

-Can be updated very quickly as changes happen. -A large number of people can access the information at the same time. -You don't need to know where to look for the information because you can use a search engine to locate relevant web pages.

3 advantages of using animation to convey information?

-Can convey a lot of information with very little text or sound required. -Can be custom made for a company to convey a particular message. -Good for catching peoples' attention very quickly.

3 disadvantages of dynamic information source?

-Changes can be made quickly and mistakes may go unnoticed. -There may be conflicting information on different web sites. -You may need certain hardware such as a computer to access the internet or a mobile phone to access information services.

3 problems caused by coding data?

-Coarsening of data, small details are lost e.g. light blue becomes blue. -Coding can obscure the meaning of data if the codes are too obscure -Coding of value judgements are hard to represent, e.g. liking something on a scale of 1-4.