Correção de texto "There is a high contrast..."

Correct my grammar, please.

"There is a high contrast in how private and public spaces are seen in the countries analyzed in this lecture. A public space is open and accessible to all citizens. Yet How far does the frontier between the public and the private go?
It was said that americans are highly individualistic; the cause of it might be that americans overvalue the private rather than the public. Which is different in other cultures, because of the different interpretations of the topic."