With the threat of $4-a-gallon gas once again hanging over the economy -- and over President Obama's re-election campaign -- the White House on Friday left the door open to tapping the country's oil reserve to ease prices.
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When consumers think the price of a good will be more expensive in the future, they will buy now at the lower price. As the number of consumers increase, the demand curve will shift to the right pushing the price of the good higher. The market mechanism, the price, then allocates the good among those consumers willing and able to purchase the good. This concept of future expectations is captured in this
Amosweb.com graph. (Note how only the demand curve moves as economists assume a static equilibrium and ceterius paribus.) Note also, that there's a change in the quantity supplied.
As the price of a good increases, producers respond by supplying more of the good. In order for producers to supply more, they have to make choices. When producers make a choice, they incur opportunity cost. In the case of ethanol, producers plant more corn that can be converted into biofuel and less corn for edible consumption.
Using a graph is mathematically rigorous, but does a cartoon say it better?
In this cartoon, Mr. Toles uses exaggeration to how the relative differences in supply and demand. The cartoon suggests that when there is a large demand for a good, the price rises.
I think this cartoon makes the point that the general public is ignorant of fundamental economics. A cartoon allows the reader to laugh at the man buying the gas because he is ignorant. But in the graph above, the reader might become angry at himself because the reader can't interpret the information contained in the graph.
I think cartooning allows the reader to learn with negative self-talk and ego defense mechanisms in a non threatening way. Plus, cartoons make learning fun which is what the high school learn wants.