This is an historic time.

This is going to be a multi-year fight.

Why is it taking so long to get a screening test?

It is not a hoax, it is real.

Something that we have never experienced before.

Wash hands, wash hands, wash hands.

I mean you're the scientist, you're gonna have to tell me.

Welcome, welcome to Science Rules, coronavirus edition.

I'm your host Bill Nye and this is the series that brings you the latest analysis and the science of this pandemic to keep you informed, prepared and calm.

We are still all in this together, my friends, and to date more than six million Americans have been infected with a coronavirus with more than 180,000 deaths.

We have roughly 40,000 people testing positive every day for the virus, but people still have questions about those tests, especially when it comes to the different types of tests and how to best use them.

I myself have been tested four times all negative by different techniques and I just wonder which one is which.

So here to help clear things up is Dr. Zoe McLaren.

She's a professor of public policy at the University of Maryland, Baltimore County, where she uses econometrics to answer public health questions.

Dr. Zoe McLaren, welcome to Science Rules, may I call you Zoe?

Of course, it's a pleasure to be here.

Thank you, thank you so much.

Before we even start about starting to begin, what is econometrics?

Economometrics is basically statistics applied in the economics realm.

So basically it's just another way of saying the word statistics.

A charming way to say statistics, but these are statistics related to public health.

Some people test positive, then the test negative, then there's negative positive positive negative, and you're not really sure what's going on.

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