With the ongoing development of artificial intelligence and sharper algorithms, our online search results and behaviors are captured and then catered specifically to our interests and needs — including when it comes to booking a vacation.

Whenever we enter a search in Google and land on a discount travel booking site, it's our assumption that these deals are made just for us and that they're the best available, but that may not always be the case. According to a study published by Northeastern University, numerous travel booking search engines are guilty of price discrimination or price steering. The study looks at hotel and rental car searches across six popular travel booking sites: CheapTickets, Orbitz, Expedia, Hotels.com, Priceline and Travelocity.

Be sure you are signed into your account

The study found that CheapTickets and Orbitz presented reduced prices on hotels to "members" who are logged into their respective accounts at the time of their search, thereby using price discrimination. Unfortunately, even though some of these practices may seem shifty they are legal in the United States.

Orbitz admits that they offer lower prices to those who have accounts on their websites. So, it pays to sign up for an account with these websites and to sign in to your account when searching for deals.

Price is affected by what device you search from

The study also found that Travelocity personalizes results for mobile users, specifically those using iPhone devices. Users who search with Safari on their iPhones received different hotels in a slightly different order than consumers using Chrome for Android and other desktop browsers.

Overall, hotel prices were listed at about $15 (or 5 percent) lower on iPhone devices than other mobile operating systems and desktop browsers, providing proof of price discrimination, where a certain group receives lower prices. Interesting to note that those with more expensive phones are rewarded.

What travel booking sites know about you

Discount booking sites personalize search results based on your account history and what you have clicked on in the past. If you clicked on or reserved a low-price hotel room, you will receive slightly different results in a much different order, compared to if you clicked on nothing, or reserved an expensive hotel room.

Priceline and other sites can customize results to show the properties that an individual is more likely to look for, and more likely book.

There’s no foolproof method to ensure you’re getting the best price. Booking sites know a lot about you and we don’t know a lot about them. If you're an ordinary person on the website, you are probably unaware that what you are presented with is based on where you have already been. The prices you are seeing have been curated for you depending on recent clicks and visits, not on what is the best price.