It depends on which course you're studying. Different nomads had different reasons. I'm sorry I wasn't able to give you a better answer.
I believe the answer is: hindsight bias
Hindisight bias refers to mindset that make a person beleive that a certain event is predictable even if they have no objective measurement to make the prediction. Hindisight bias generally created by either memory distortion or self fulfilling prophecies.
The last few decades have seen significant changes in the percentage of women's workforce, especially mothers with underage children, most of whom are working full-time. For example, from March 1975 to March through March 2000, the percentage of mothers with children under the age of 18 rose from 47% to 73%. Thus, According to the data of the U.S. Bureau of Labor Statistics in 2007, this percentage is 71%.
Answer:
This is true because due to push and pull factors information is spread.
Explanation:
For example if a U.S. company moved to China for a better business opportunity then the ideas and cultural backgrounds would travel as well.
