Movement Along a Curve versus
Shifting the Curve
To draw a curve showing the
relationship between hours worked
and income, we fix the weekly
allowance ($40) and the wage ($8
per hour).
A change in the hours worked
causes movement along the curve,
for example, from point b to point c.
A change in any other variable shifts
the entire curve. For example, a $50
increase in the allowance (to $90)
shifts the entire curve upward by
$50.