If you're confused about whether the US economy is in a recession, you're not alone.

On one hand, gross domestic product, a key measure of economic output, shrank for the second straight quarter this week, raising fears that the country has entered -- or will soon enter -- recession territory. On the other hand, the job market remains very strong, telling us the economy is still robust.

Some economists call two consecutive quarters of contraction a technical recession. And with good reason: 10 out of the last 10 times the US economy shrank for two consecutive quarters, the US economy was declared to be in a recession. But massive job losses occurred during seven out of the past seven recessions, and that's not happening now.

There's no steadfast rule governing what defines a recession in the United States. Instead the official designation is determined by eight economists who serve together on the Business Cycle Dating Committee. The group works under the umbrella of the National Bureau of Economic Research (NBER), a private nonprofit organization. It has yet to use the "recession" label.

They abide by a relatively vague definition that allows for wiggle room: A recession, they write, "involves a significant decline in economic activity that is spread across the economy and lasts more than a few months."

So are we in a recession, really? It's hard to say. But here's why we may be. And why we may not be.