Question

Discuss the problems you see in comparing the GDPs of two countries, say, the United States and the People's Republic of China.

Short answer

Directly comparing the GDP's of nations like United States and People's Republic of China can be misleading due to variances in population size, exchange rates, cost of living, nominal and PPP adjusted GDP and most importantly, the structural differences of the economies.

Step-by-step solution

- Understand the basic definition and calculation of GDP

GDP is the total economic output of a nation within a specified time period. It represents the monetary value of all goods and services produced in a country. It's calculated by adding Consumer spending (C), Investment (I), Government spending (G), and Net exports (X - M). GDP = C + I + G + (X - M)

- Evaluate the impact of population size

When comparing GDPs, the population of a country can influence the comparison. For instance, a country with a larger population may have a higher nominal GDP disregarding the actual standard of living or well-being of the citizens. So comparisons are better done using GDP per capita which takes population into account.

- Assess the effect of exchange rates

Exchange rates matter for international comparisons of GDP. If a country's currency is undervalued, it will artificially lower its GDP when converted to dollars. Same is true vice versa. Hence, comparisons taking into account purchasing power parity (PPP) are apt.

- Factor in the effect of living costs

The cost of living in different countries varies widely. If the cost of living is low, the citizens can maintain a higher standard of living even with a lower GDP per capita. So, cost of living adjustments are necessary when comparing GDPs.

- Consider the difference in economic structures

Countries can have different economic structures. For instance, the US economy is service-oriented while China is more manufacturing-oriented. Such structural differences can impact GDP and thus the comparison.