Cambridge International as and a level Economics Ebook

SELF-ASSESSMENT TASK 
2.18
1
In each of these cases draw a diagram to show 
how an increase in the price of the fi rst good will 
aff ect the demand for the second good:
a 
Lipton tea and Tetley tea
b 
Ink cartridges for a PC
 
and computer paper.
2
In each of these cases draw a diagram to show 
how a fall in the price of the fi rst good will aff ect 
the demand for the second good:
a 
Duck and chicken
b
Cricket bats and cricket balls.
Fashion, taste and attitudes
We all buy products for a reason: our behaviour 
is purposefully motivated, at least at the time of 
purchase! Economists usually consider our behaviour 
to be a refl ection of our tastes and preferences towards 
diff erent types of goods and services. You may buy a 
particular type or brand of PC because of its reputation 
for reliability. You may buy a pair of brand-name 
trainers because you want to play sport and you 
genuinely believe them to be of better quality or you 
may buy them simply because they are fashionable and 
you want to look cool.
Detailed understanding of the psychological motives 
that determine our behaviour are beyond our scope here, 
but clearly we are infl uenced by our own individual likes 
and dislikes, by peer pressure and by various forms of 
advertising and the marketing images that surround us. 
Nowhere is this more evident than in markets for designer 
58
Cambridge International AS Level Economics

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SELF-ASSESSMENT TASK 
2.19
1
Suppose there has been an outbreak of chicken fl u 
in a particular country. Use a diagram to show how 
this is likely to aff ect the demand for chicken in that 
country. Explain your answer.
2
Medical trials have indicated that drinking erh-pur 
tea from Yunan in China can reduce blood pressure 
and cholesterol in Europeans. Use a diagram to 
show how this might aff ect the demand for this tea. 
Explain your answer.
Nike trainers – a fashionable designer brand
clothing and accessories, where tastes and preferences can 
be extremely volatile.