answer is quite easy, employment data is a lagging indicator. to prevent econ from overheating , a preemptive strike is necessary.

I do agree with you part of it. Firstly. There is no doubt that employment rate increase will cause economic increase too. The question is why you think it will cause the economic overheating.

First, From March 2009 to the present, the US stock market Nasdaq index soared 294%. On the other hand, although the US economy has improved under the flooding of water, it is far from being able to support the 194% increase in US stocks (the debt ratio is as high as 300%). Therefore, to raise interest rates is to prevent the stock market from being overheating. please see the pic 1
next picture is the stock nasdaq index in 2014, though there was a drop in Oct, the price soared rapidly. incresing interest rate was not an issue

second, The Fed’s interest rate dropped for many years, which have led to the lowest interest rate in the US, and the following is the US interest rate chart.

as we know he lower the interest rate means that the tools in the toolbox are getting fewer and fewer. In the future, if there is a financial crisis, it will be very passive. Therefore, the Fed uses the current economic opportunity to raise interest rates slowly. The unemployment rate is generally judged by the economic good or bad. The important indicator is that the current US unemployment rate is 4.3%, which is a very low level.

2014年8月至11月，新增非农就业人数稳步上升，美国经济复苏。美联储提前加息。这个例题有问题吧.

I m very appreciate the way you are thinking. The thing I need to say is that none of us are wrong. The wrong thing is the question itself. Because it only said the US federal government will increase interest in advance. It didn’t say increase in which level? however, your summary was that interest will increase slightly. Thank you for your answering.

美国经济这几年一直在复苏，但不一定经济复苏就一定要降息，它是一个综合的考虑。像我上面说的，本来利率就已经很低了，如果不加息，一旦遇到金融危机，财政政策就基本没用了因为不能再使用降息政策等等。如果你有关注，上几个月特朗普一直批评财长，不满他为什么经济增长那么好还要加息。我想财长一定是担心经济发展过热。所以顶住压力也要加息。这里面其实有一个隐含的冲突。就是理论和实践的区别。很多理论是有很多前提假设的。一般都很难运用在实践当中，因为现实问题要比假设来得复杂得多。