Do countries with a higher urban population have a higher HDI?

In a multivariate research course, I must present a hypothesis of a causal relationship between two variables while controlling for spurious or intervening variables.


I was thinking that the basis of my hypothesis would be that as urban populations grow, Human Development will become higher. (Additionally, in countries with higher rural populations, we can generally expect a lower HDI.)


The relationship between the two variables is linear, has a corr of .78, and slope= .33+ .006x.


The t-value for the coef is 12.59, R-squared is 61.7, and the P-value is 0.00.


All looks good except the slope and intercept, though there is a relationship, is the effect of X on Y too small? All other data seems to indicate statistical evidence.





Any help would be appreciated, especially with overall identifying significance (if there is one because of the slight change in "Y") of relationship and interpreting F-value === F(1, 98) = 158.39, Prob %26gt; F ) = 0.0.





(This is about 30% of my grade for the course, professor gave us 'til Monday to do it...I know I'll get a "do your own homework" response but I'm looking for honest help. I'm not a statistician and this is a time-crunched assignment.)|||Urbanization is probably not causal in this case.





There is a very strong correlation between GDP per capita and HDI


http://freakonomics.blogs.nytimes.com/20鈥?/a>


and as a country moves from under-developed to developed, the percentage of the population that is rural declines and the percentage that is in the metropolitan areas increases. That gives the correlation between HDI and urbanization.





This is because as the economy develops, agricultural workers become more productive. That means the rural areas need fewer workers so the workers have no choice but to go to the cities to find jobs in the factories.





This has been the pattern in every instance of industrialization, from England, centuries ago,


http://en.wikipedia.org/wiki/British_Agr鈥?/a>


through China today.


http://en.wikipedia.org/wiki/Urbanizatio鈥?/a>





For example, in the U.S. less than 0.6% of the labor force is in agriculture:


https://www.cia.gov/library/publications鈥?/a>


For Bangladesh, with a per capita GDP 1/40th that of the U.S.,


http://en.wikipedia.org/wiki/List_of_cou鈥?/a>


the percentage in agriculture is 63%


https://www.cia.gov/library/publications鈥?/a>


For India, where the per capita GDP is 1/20th that of the U.S., 60% of the labor force is in agriculture:


https://www.cia.gov/library/publications鈥?/a>


While for China, where it is 1/9th the U.S. per capita GDP, it is 43%


https://www.cia.gov/library/publications鈥?/a>