Today we use non-aggregate model and add technology change and make it fluctuate
according to some random process. We approximate the continuous random model:
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by switching model with infinite many states in order:
![]()
.
.
.
where
![]()
![]()
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.
.
.
for many states.
We calculate each policy function for each
as it is set like:
independently for each i and calculate the next index number.
The random process
can be
![]()
for
as in 0818.
The random movement of technology change(A
sample path of
)

The corresponding capital movements

where the gap will not pile up because we usually do not use the same policy functions
in a row. The gap may become zero or very small in the middle.