I have to write a short summary of all three of the economic noble prize 2021 winners. I don't need information on Card. My main problem is I don't understand specifically what Angrist and Imben's work really is. I need to understand them separately because so far I am not seeing a difference in their work. It appears as though they partnered up but my professor wants me to write about each one separately. When I read the summary on the Nobel Prize page it literally makes no sense and I have no idea how to explain each economist's work in my own words. Also, I am having a difficult time finding any detailed information that provides a clear explanation of Joshua D. Angrist and Guido W. Imbens'swork that led to their winning the noble prize. Can you clearly and separately explain each of their contributions, independent of each other, that led to the importance of natural experiments in economics to me? For example, I understand that their work is tied but can you explain ( more like teach me) about each economist work by explaining exactly what each did, what made each special economist work different or special for the others, how was it used, and how they tied each other work together and how it will make a difference to future economist that caused them to win the Nobel prize. Unfortunately, I need it asap.