BTEC L3 IT Unit 5 Data Modelling, Learning Aim A1: introduction

1. Unit 5 Data Modelling
A1 STAGES IN THE DECISION-MAKING PROCESS
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2. This section covers :
1. Understanding the scenario.
2. Identifying information and sources.
3. Factors affecting the quality of information.
4. Analysing the information.
5. Identifying alternatives.
6. Identifying consequences of implementing the alternatives.
7. Making a decision.
8. Justifying the decision.
9. Communicating decision(s) to others
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3. Understanding the scenario.
A scenario describes a situation where a problem exists that needs to be
addressed. It will include some details on the problem, a required
solution and a time frame.
Most scenarios are incomplete. This may not be deliberate, but due to a
lack of information, or a lack of clarity on the required solution.
A key skill in developing a solution is Systems Analysis. This can be
summarised as:
 Identifying what is currently done
 How the task is currently done
 What the problem is
 What is the proposed logical solution
 What is the proposed physical solution
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4. Identifying information and sources.
 Information required
 Information that is already available
 Additional information needed
 Sources of additional information
 Requirements for verifying the information sources.
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5. Factors affecting the quality of information.
Currency - time sensitivity of the data
On August 1st 2021 the price of Gold was £1306.08 per oz.
On July 1st 2021 the price of Gold was £1296.27 per oz
On June 1st 2021 the price of Gold was £1348.96 per oz
This asset price is governed by pure supply and demand (excluding
speculation).
Consider the implication of buying and selling items at different
prices if you use the wrong purchase and sale price figures.
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6. Factors affecting the quality of information.
Accuracy
 1) Accuracy relates to the difference between the data used and
the actual data.
 If the data used is 14, 18, 23 and the real data is 11, 15, 20 the data being
used is inaccurate. In this example it is consistently inaccurate, all values
are 3 more than they should be.
 If we look at data being used as 7.2, 12, 14.4 when the real data is 6, 10,
12 the data is consistently inaccurate by 20% over actual.
 These 2 cases can be rectified mathematically by reversing the
discrepancy.
 If the values are different by a varying margin, this is unable to be
rectified.
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7. Factors affecting the quality of information.
Accuracy
 2) Precision is how “precise” the data is – the number of
significant digits.
 As an example a tray of 24 tins is purchased for £37.50 which gives a price
per can of £1.5625.
 If we use a mark-up of 20% the selling price per tin is £1.875.
 Precise, (and accurate), but of no real-world use.
 Scientific notation, e.g. 2.563 *10^6 is really 2563000 are the last 3 digits
really all 0? This can result in approximation, but on certain values this is
acceptable.
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8. Factors affecting the quality of information.
External factors
 SWOT analysis.
 Strengths and Weaknesses are internal, you can control.
 Opportunities and Threats are external, you have no control.
 Consider each of the following and how they can have an impact:
 Government changes a rate of tax (NI, VAT, Income Tax)
 You import/export goods and are unable to do so (9/11 grounded all flights
for an extended period, the current Pandemic)
 Exchange rates move up/down
 Asset values change due to changes in demand.
 Health and Safety legislation changes
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9. Analysing the data.
 Data is the values in the spreadsheet, Information has context.
 Looking at the data in context:
 What can we see at the current time?
 What trends are there ?
 Can we identify e.g. the good and weak sales and is there a reason?
 Is it best displayed as numbers, or graphically?
 Does statistical analysis show anything
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10. Identifying alternatives.
 In programming we have different PARADIGMS
 Object oriented, Structures, visual etc
 Each results in a different approach to the task.
 What different alternatives are there in spreadsheets
 Organisation of the spreadsheet
 “efficiency” of calculations
 Data entry by “keyboard”, dropdown or slider.
 Internal/External access to data
 Each different point you consider could generate an alternative
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11. Identifying consequences of
implementing the alternatives.
 Each alternative will have its own benefits and drawbacks
 This is about identifying the differences of each alternative
 You must compare like to like, so the list of points is the same
 What is the degree of difference
 Is 2 days significant on a 6 month contract?
 Is £150 significant on a £5000 contract
 Each point could have a variance – difference from that of the others
 Here you are only identifying the consequences
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12. Making a decision.
 Decisions have to be based on justification of a number of points.
 What are the key points,
 How do they apply to each alternative
 How do you “score” them to identify the best to worst.
Consider how I could put each of you in order of “best” to “worst”
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13. Making/Justifying the decision.
 The decision you make could be challenged – WHY do this?
 What data are you working with
 What options were considered?
 For each option what were the characteristics you considered
 How were these weighted
 How did you come up with the weightings
 What was the ranking of “best” to “worst”
 If yours isn’t “best” Why
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14. Assessment note
GENERALLY
 Gathering the data and explaining it equates to PASS criteria
 Comparing or Analysing data equates to Merit criteria
 Evaluation of options and justification equates to Distinction criteria
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15. Communicating decision(s) to others
 It is unusual for you to be the sole member of the team
 Your colleagues need to know what is happening
 Plans for all to follow
 Understanding of individual roles and deadlines
 You work with a team leader who holds responsibility
 Needs to know what is going on, and when, and by whom
 Your work is for a client
 Who needs to be kept informed of progress and problems
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16. Task
This link opens a Moodle task.
There is insufficient detail to produce a “solution”.
Using the previous work, identify, using the 9 points, what further
information you need to be able to address all of the points
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