CO4001 – Data Analysis

Modelling 2Charts, Text Box and Multiple worksheets

Data Handling

• Database– Record keeping– Add, delete, edit, select, sort– Avoid duplication of data

• Enter once• Store in one place• Use in many ways and places

• Spreadsheet– Algorithms (calculations, look-up, functions)– Primarily numeric data – Option to present results graphically

Spreadsheet

• Problem definition• Model

– Constants– Variables– Parameters

• Process model– Formulae– Functions

• Human-Computer Interface– Data entry and validation– Results– Automation

What many people find difficult

Method

• Design spreadsheet• Testing

– Right answers when input variables change?– Is format OK?

• Set input cells to initialised state and cursor to ‘home’• Protection

– Unlock input cells then activate protection• Last check

– Is it suitable for the user’s skill level?– Does it meet the user’s requirement?

• Save spreadsheet

Data

• Variable– Value changes frequently

• Constant– Value NEVER changes (e.g. number of days in a week)

• Parameter– Value chosen for particular use of the spreadsheet (e.g. today’s

date, number of people present)

Table versus Chart?

• A chart often presents information more clearly

Jan Feb Mar Apr May Jun Total

John 80 82 85 75 80 90 492

George 30 35 38 25 40 43 211

Sue 50 54 58 43 55 61 321

Sally 48 51 55 60 61 63 338

Task 1 Table versus Chart?

• Who has highest total sales? Who has lowest sales in March?• Who has highest sales in June? What is % share of total sales?

Jan Feb Mar Apr May Jun Total

John 80 82 85 75 80 90 492

George 30 35 38 25 40 43 211

Sue 50 54 58 43 55 91 321

Sally 48 51 55 60 61 63 338

Who has highest total sales?

Total sales

0

100

200

300

400

500

600

John George Sue Sally

personnel

pro

du

ct

Total

Who has lowest sales in March?(rows in legend)

0 20 40 60 80 100

Jan

Feb

Mar

Apr

May

Jun

Sally

Sue

George

John

Who has lowest sales in March?(columns in legend)

0 20 40 60 80 100

John

George

Sue

Sally

Jun

May

Apr

Mar

Feb

Jan

Who has lowest sales in March?(stacked bar chart)

0%10%20%30%40%50%60%70%80%90%

100%

Jan Feb Mar Apr May Jun

Sally

Sue

George

John

What is % share of total sales?

“Horses for Courses” – choosing chart type

Sales

0

20

40

60

80

100

Jan Feb Mar Apr May Jun

1998

Un

its

x 1

,00

0John

George

Sue

Sally

Sales

John36%

George15%

Sue24%

Sally25%

0

50

100

150

200

250

300

Jan Feb Mar Apr May Jun

Sally

Sue

George

John

Each person’s ‘share of the cake’

What has each person contributed to the total, month by month ?

How do people compare, over time ?

Create a column chart

Column chart

Chart Layout - Title and Axis labels

Switch data – row to column

Change style of chart

Move chart to a chart sheet

Name sheets

To improve the design of your spreadsheet give sheets meaningful names rather than sheet1 sheet2 etc

Click on sheet tab

Select Rename

Type new name

e.g. ToyData

Change the chart type – Column to Bar

Lies, Damn Lies, Statistics … and Charts

• Scales can make the chart present a misleading view

Not Really

1000 1001 1002 1003 1004 1005

0

200

400

600

800

1000

1200

2000 2001 2002 2003 2004 2005

Year

Pri

ce

Big Trend?

10001001

10021003

10041005

997998999

1000100110021003100410051006

2000 2001 2002 2003 2004 2005

Year

Pri

ce

Text box to describe chart

In your assessment a text box containing justification for choice of chart is required

Move to required named sheet

Click Insert Text Box

Hairline appears drag and daw required bovx in required position

Enter text

Multiple worksheets

In your assessment worksheets need to be named and linked

If data on toys on ToyData sheet and analysis to be on ToyAnalysis sheet

Move to ToyAnalysis sheet enter =AVERAGE(click on ToyData sheet, click list of toys required i.e. B4 to D4 close bracket)enter

=AVERAGE(ToyData!B4:D4) appears on ToyAnalysis sheet

Workshop

• Exercise 2.1 – Toys charts• Exercise 2.2 – Deliveries chart and text box• Exercise 2.3 – Ratio Analysis and multiple worksheets• Exercise 2.4 – Cars charts• Exercise 2.5 – Accounts charts