Theory of Optimal Currency Areas Should a country be more inclined or less inclined to join a currency union (common currency) under the following events:
a) Increase in the size and frequency of AD shocks to the economy.
b) Increase in the size and frequency of money demand shocks to the economy.
c) Increase in the cultural similarities between the country and the country or region it is joining.
d) Decrease in capital mobility restrictions combined with an increase in immigration restrictions.

In case a, I feel as though it depends on whether or not the AD shocks are similar between the joining regions; if they are, then they would be more inclined, but if they're not, then otherwise.
In case b, I think the country would be less inclined since they would have less control over monetary policy.
In case c, I would say more inclined because it would encourage labor movement.
Finally, in case d, I would say less inclined because, although capital would flow freely, a decrease in labor flows would be worse.
What are your thoughts on these four cases?
a) Increase in the size and frequency of AD shocks to the economy.>


More inclined would encourage more demand from other regional countries, which in turn supports the shortage of domestics demand


  b) Increase in the size and frequency of money demand shocks to the economy.>


Less inclined would be better since independent currency regime provides local goverment (ie. the central/state bank) more flexibility in controling supply and demand money in order to deal with money demand shocks


  c) Increase in the cultural similarities between the country and the country or region it is joining.>


More inclined should be a great idea in this case as countries in that region could exchange labor and goods at lower relative cost compared to remain local currency regime


  d) Decrease in capital mobility restrictions combined with an increase in immigration restrictions.>


More inclined to common currency is my answer. Common currency is not the same as establishing an OCA (Optimal Currency Area) so immigration is a less-crucial criteria than capital mobility in considering a decision of commmon currency.