IB ESS HL 8.1 Human Populations Question Bank

Outline the similarities and differences between "crude birth rate" and "natural increase rate".

Differences:
a. Crude birth rate (CBR) is the number of (live) births per 1000 individuals / CBR focuses only on births;
b. Natural increase rate (NIR) is the CBR - CDR divided by 10 / NIR is expressed as a percentage / NIR takes both births and deaths into account;
c. NIR can be negative / CBR may assume only a positive value;
d. Can estimate doubling time, if divide 70 by NIR;
e. NIR is a more accurate/direct indicator of population growth;

Similarities:
f. Both involve number of births in their calculation;
g. Both refer to mean values;
h. Both give some indication of potential for growth;
i. Both are (usually) annual values;
j. Same data sources/data collection methods for both (census, civil registration, household surveys);
k. Both are required for assigning a country into a specific stage of the Demographic Transition Model;
I. Both exclude immigration and emigration.

Note to examiners: Allow [3max] if only differences or only similarities.

Answers may demonstrate:
- understanding concepts \& terminology of population policies; development policies; anti-natalist/pro-natalist; China's one child policy; female emancipation; gender equality; contraception; child benefit/child tax; population pyramids; population momentum; demographic transition; sustainable development; limiting factors; carrying capacity; S-J curves; DTM; demographic tools (CBR, CDR, TFR, DT, NIR);
- breadth in addressing a range of population and development policies and linking them to their impact on the stability of various human populations and comparing their success.
- examples of relevant national \& international population policies and their degree of success in stabilising the population;
- balanced analysis comparing various population policies from a range of countries and evaluating the extent to which these policies managed to effectively stabilise the population on which they were implemented.
- a conclusion that is consistent with, and supported by analysis and examples given e.g. Economic incentives and disincentives can be effective in curbing the growth of human populations, but, generally, the most effective means of stabilising growth seems to come naturally with the development of populations, as evidenced by the relatively stable MEDC populations.

Note to examiners: There is a definition in literature of stable population having stable (=constant) demographics, i.e. CBR, CDR, age structure, but also NIR! Thus it contradicts the definition of a stable population as one with a constant population size (CBR = CDR). Do not penalize the former, although, most probably will lead to convoluted analysis. A response should not earn the higher MBs, unless addressing the latter definition.

Please see markbands on page 23.