Purchasing treasury means FED is injecting money into the market. Here is the effect of FED decision:
1. More money in the market raises inflation.
2. More money flow into the market makes more US dollar available. The more US $ available, the less desirable dollar becomes. Hence, US $ weakens.
3. Since FED is buying, yield has fallen
4. Since bond yield has fallen, mortgage rates have fallen.
Net impact - Overall, the currency has weakened. Mortgage rates have fallen. Gold price has risen.
1. This is good for housing sector.
2. This is also good for global domestic comanies - this will thelp their earning.
3. But, will raise inflation. To contain inflation, FED would raise interest rate.