Question

Bearman and bruckner (2001) found that teens who made a public virginity-till-marriage pledge became somewhat more likely to remain sexually abstinent than similar teens who do not make the pledge. this is an example of how status produces psychological reactance. teens seek to maintain emotional distance from would-be sexual partners. prior commitment reduces susceptibility to social influence. there is cohesion in a group.

Answer 1

I believe the answer is: somewhat more

When a person make a public virginity-until-marriage pledge, they tend to be more likely to feel some sort of social pressure to follow on their words in fear of being seen as a hypocrites by other peers. This would indeed improve their likelihood to stay a virgin,   But the effect of the social pressure tend to diminish over time