Session 5

Secondary Data

So what is secondary data?

• Secondary data is data which exists

• Secondary data is a reflection of a

situation which occurred at some time in

the past

• Secondary data is therefore always

historic

• Primary data is data which does not

exist, at least in the time frame required

Always remember, never forget!

• YOU ALWAYS COLLECT SECONDARY

DATA BEFORE PRIMARY DATA

Why? Because it is cheaper !!!

The problems with secondary data!

• It was not originally collected with you in mind

• It may be out of date

• It may use different forms of measurement

• Is the data consistent with our problem?

• Is there adequate detail?

• How accurate is it?

• Do the authors have a vested interest in it?

• Can it be cross checked?

Ways to lie with secondary data

• Change the criteria of measurement

• Include the mid point in your calculations

• Elongate the scale

• Position your typography to be suggestive

• Inconsistency between facts and

conclusions

• Selective perception / selective retention

Data Mining at Tesco’s

• Data is collected by POS from shoppers, 92% of

whom are Clubcard members and who get a 1%

discount on all their goods.

• Data is cross tabulated and cluster analysed into

groups of customers who are “customised”

through multimedia channels of promotion

• Data mining adds 3.5% to Tesco’s profit (2.8%

net). Being done in Thailand by Tops (?)

Classification of Secondary data

• Based on two criteria:

• Cost (ranging from free to expensive!)

• Availability (open access to very restricted)

• Cost normally determined by method of funding / funding agency.

Free and open access sources

• The Internet

• Books, periodicals and journals

• Governmental sources (national and

regional), census and consumption

• Media sources

• Commercial sources

• Investment analysis

Cost and Limited access

• ACORN and TGI

• Mintel and Keynote (UK only)

• Customer derived data from POS

A Classification Of Residential

Neighbourhoods

• Based on UK census data

• Derived by cluster analysis of selected variables taken from the data

• Each of 1.6 million postcodes has a unique ACORN classification, split into 54 types, 17 categories and 5 groups.

• Used to determine patterns of consumption in conjunction with TGI (Target Group Index)

What is ACORN used for?

• Market potential estimation

• Retail outlet determination

• Customer targeting

• Sample selection

• Media selection

“ACORN / TGI is used by over 85% of retailers in the UK, and all major ones”

Target Group Index

• Based on 25,000 annual survey covering

over 5,000 products in 600 categories

• Data expressed as an index where 100 =

national average consumption

• Used in conjunction with ACORN for store

location

• Used extensively by the media for

evaluation of different mediums.