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Articles including the ads: on the left side two samples of articles including display ads are shown, while on the right side, the same samples including native ads are shown. Each sample, regardless of the ad format, shows three ads of the total four, since the fourth ad, to be seen by the user, is required to scroll, an action that each participant performed to read the article. The third ad located in each sample was fixed and always visible while scrolling the page.
