Data is necessary even if we use common sense.

"After years of stressing the importance of evidence-based policymaking, economists have clearly had some influence on politicians," wrote Prof K Basu. "What economists now need to do is to impress upon the same politicians that citing any evidence before adopting policy is not evidence-based policymaking at all." President of Turkey, RT Erdogan used some figures to engineer short term growth with state-guaranteed credit, resulting in inflation of 12%. Granted 12% is high, but we are told that retail inflation of 4% is fine for India because it is mostly due to food. But, surely high food prices will lead to higher wage demands which will force companies to raise prices of goods and services, thus causing inflation in all sectors of the economy? Donald Trump cites huge deficits in trade with other countries to call for protecting jobs at home, but this will hurt the very people he is trying to protect. US government debt is already over $20 trillion so Trump is right to worry about it, even if most of it is at home. "Theorist Eric Maskin: Globalization is increasing inequality," wrote N Berger of the World Bank. "The right thing to do is not to try to stop globalization -- that would be foolish -- because globalization certainly does increase average income in all countries," said Nobel Prize winner, Maskin. "Rather, what we want to do is allow the low skilled workers of the world to share in the fruits of globalization." But, how? Maskin recommends training low skilled workers. Trump is a businessman. He knows that a plumber or mason cannot be retrained as a computer engineer. Politicians have to think about the whole country when deciding policy. In a referendum Catalonia voted for independence from Spain mainly because "Catalonia contributes 119% of national resources compared to the national average, but receives only 102% of the national average after central government redistribution", wrote
Prof V Dahejia. For every Rs 100 a citizen of Maharashtra contributes to national coffers she receives Rs 15, compared Rs 420 for a citizen of Bihar. Basu recommends using common sense. "While there is certainly value in collecting data (via, for example, randomized controlled trials), there is also a need for deductive and inductive reasoning, guided by common sense -- and not just on the part of experts." But, human beings make economic decisions on moral and altruistic reasons and not solely based on logic, wrote Prof R Hausmann. Perhaps, decisions made by Erdogan and Trump are based on "common sense", as Basu recommends. Human beings have emotions, economics is data. Not the same.