Hello, for my Thesis im trying to measure the impact of online product review characteristics on perceived source credibility and purchase intention, i am planning to do this by employing a 2x2 factorial design 2 (Review Valance - Good - Bad) x 2 (Review Quantatiy - Few - Many).

Roughly, the experiment would work like follows: Introduction -> Show respondent randomly assigned one of four manipulated product review (God -Few, God - Many, Bad - Few, Bad -Many) -> measure perceived source credibility & purchase intention. However, my problem here is that i dont know how i could implement a control group in this scenario, when im just showing a product i have no ground to measure source credibility as there simply is no review present.

Hopefully im not on completely wrong tracks here, hopefully someone can help here or offer some imput :)

Thank you!