You’ve surely noticed that digital marketing has become more sophisticated. Maybe you can recall a pair of shoes that seemed to follow you around the web for weeks. Or perhaps, just days after adopting a puppy, ads for organic dog food popped up in your social-media feeds.

But how effective are these ads really? And, should you care to, can you get them to stop? We have gathered a list of common perceptions—or misperceptions—about the industry and asked a pair of experts to tease them apart: Which are true and which are false?

Take the quiz below. Then learn from Kellogg’s Brett Gordon, an associate professor of marketing, and Boston University’s Garrett Johnson (formerly a visiting assistant professor at Kellogg) just how much your perceptions of this quickly changing industry match reality.

When I go online, websites track a lot of information about my movements and actions.

Digital advertising is so sophisticated that marketers know what I will probably purchase tomorrow.

Most people never click on ads—so they must not really do anything.

Psychographic ad targeting—where people are targeted based on various psychological attributes—has been proven to be especially effective.

Spending on digital advertising is growing quickly and is now as big as spending on TV advertising.

Platforms like Facebook and Google are just trying to sell me things I don't need or want.

Customers demand privacy. So if offered the chance, lots of customers would pay to keep their data completely private on platforms like Facebook.

When I go online, I have no control over what data are collected about me or how ads target me.