W14 posting by han seung gu

1.Summary

Demography is the study of human population dynamics.
It represent the whole societies.Demography relies on large data sets.And it focus on specific indicators of change. But accurate numerical values are often difficult to achieve.
There are various studies about demographic.
Fertility that ability of females to produce healthy offspriing and
Fecundity that the potential reproductive capacity of a female are one example of demographic.
And demographic transition means that The transition from high rates to low rates is referred to as the demographic transition.
#Overpopulation is a ratio: population over resources.
It has some problem: Child poverty,High birth rates,Lower life expectancies....
And there are several arguments for solving this.
First, a huge number of plant and animal species become extinct. So it result in terrible pollution in some areas that would be difficult to abate
Second,disease or starvation are "natural" means.
Third,economic development can reduce population growth.
#Urbanization is the physical growth of urban areas as a result of global change. it's movement of people. It has some effect.
Economi effects: a dramatic increase in costs, pricing the local working class.opportunities for jobs, education, housing, and transportation.
Environment effects:the urban heat island., prevent overpopulation ,leaving more for nature,puts a stop to destructive subsistence farming techniques.
And Urbanization varies in shape as the age changes.

2.Mention and Question. 

This chapter is ineresing to me. Because I have a lot of interest in this part.
I knew roughly about this part, but I did not know it professionally.I read this article and learned a lot about demogrphic. And I simply thought it would be a problem if the population was small. However
read this document, I realize that overpopulation  is also a problem.
I have a Question. It is a problem of all statistics. A sample of statistics can not be done by everyone.
So What are some ways to increase the credibility of statistics except for increasing specimens?