Questions: The main goal of the unemployment insurance system is to reduce workers' uncertainty about their incomes. the rate of job separation. the search effort of those who are unemployed. frictional unemployment.

The answer is the first one: to reduce workers' uncertainty about their incomes.

Explanation for each option:

1. To reduce workers' uncertainty about their incomes: This is correct. The primary purpose of unemployment insurance is to provide temporary financial assistance to workers who have lost their jobs through no fault of their own. This helps to stabilize their income during periods of unemployment, reducing uncertainty and allowing them to meet basic needs while searching for new employment.

2. The rate of job separation: This is incorrect. Unemployment insurance does not directly aim to reduce the rate at which workers lose their jobs. Job separation rates are influenced by various factors, including economic conditions and industry-specific dynamics, rather than unemployment insurance.

3. The search effort of those who are unemployed: This is incorrect. While unemployment insurance provides financial support, it is not designed to reduce the search effort of unemployed individuals. In fact, recipients are typically required to actively seek employment to continue receiving benefits.

4. Frictional unemployment: This is incorrect. Frictional unemployment refers to the short-term unemployment that occurs when people are between jobs or entering the workforce. Unemployment insurance does not specifically aim to reduce frictional unemployment, although it may indirectly affect it by providing support during job transitions.

In summary, the main goal of the unemployment insurance system is to reduce workers' uncertainty about their incomes.