1. Comparing Crop Yields Effect of the Change from a Command Economy
to a Market Economy

2. Since the breakup of the Soviet Union,
wheat yield in Russia has gone up.
Part of the gain is because they just stopped farming
about 20% of the worst land.

3. Meanwhile, wheat yield also went up
for the world as a whole.

4. An important point: yields went up
even faster in countries like Mexico.

5. to “smooth out” year-to-year variations.
You can add trend lines
to “smooth out” year-to-year variations.

6. Comparing these trends
leads to one simple conclusion:

7. BUT the increase Comparing these trends
Wheat yields in Russia
did go up after the change
from a “command economy”
to a “free-market economy,”
BUT the increase
was basically the same
as the world average.
Comparing these trends
leads to one simple conclusion:

8. more complicated graphs,
Here are three
more complicated graphs,
each one making
a simple point:

9. Grain area
in Russia
went down
about 20 %.

10. Wheat yields
in Pakistan
and India
are low,
but they
are rising
faster than
in Mexico.
And yields in Mexico
are rising faster
than in Russia.

11. that grain yields are reaching
There is
some evidence
that grain yields are reaching
some kind
of limit.

12. Here’s the question:
How do we start
to give children
the tools to evaluate
assertions about
cause and effect?