.........首先，利率和收入并没有必然的联系，要是有的话只要抬高或降低利率那百姓就能富起来了。IS-LM模型里面利率和收入之间的关系并不是他们之间的决定于被决定的关系，而是通过总需求总供给推到出来的，其中IS曲线是是结合了投资函数表示的r和I之间的相互作用与凯恩斯交叉图表示的I和Y之间的相互作用，以此推导出的r和Y之间的关系，同样LM是由货币需求函数和流动偏好理论推导出来的r和I之间的关系。
总之，概括来说就是他们之间没有必然的关系，只是通过其他关系间接地联系到了一起，用来旨在分析短期经济中物价水平不便的经济波动问题

楼上正解

Simply speaking, in the short run, under the assumption of sticky price, output is determined by the aggregate demand (however, in the long run, output is decided by supply which in turn depends on these factors, like labour, capital, education, and technology...), and output can be seen equal to income. Based on Mundell-Fleming model (which is just a similar model as IS-LM in open economy, lower interest rate (say as a result of expansionary monetary policy) will raise the investment, thereby expanding aggregate demand, on which output is determined in the short run.
However, it is worth noticing that low interest rate will therefore reduce saving by individuals and this repercussion reduces level of capital within a country in the long run. Hence, a continuous low level interest rate in the long run will be detrimental to a country`s economy, worsening output rather than improvement.

恩恩 谢谢ls各位老师的解答，谢谢

``好想是这么回事··要回去翻翻课本才行了··基本都忘掉了··

Put another way, according to AA-DD model, lower domestic interest rate will cause domestic currency depreciating (interest parity condition). As a consequence, current account improves (this conclusion is derived from Mashall-Lerner theroy), and aggregate demand for domestic goods thus increases. Output, which is equal to demand in the short run, is increased.

这只是IS-LM模型,在其他条件不变的情况下,收入才会增加。

1# 江上輕舟
l利率降低，所以投资旺盛（i=e-dr），收入增加。

我是这样理解的，这里的收入不是指个人收入，而是指总收入。在其他条件不变得情况下，利率降低，则投资增加，带动产出增加，根据IS曲线的收入恒等式Y=C+I+G，总收入增加

利率与收入没有必然的联系。

利率与收入没有必然的联系。

还有一点就是消费也增加。

谢谢楼主的提问，在你问这个问题之前，我还没注意到这个问题。