You know what, Brick might just love lamp.

This classic clip shows beloved Brick trying to convince Ron that he really does ‘love lamp’ (0:15). By repeating his undying love three times, the audience should be more likely to believe and accept his statement according to Pratkanis’ repetition technique. This is supported by a study into advert claims (Hawkins, Hoch & Meyers-Levy, 2001). In this study, participants were asked to read 20 sets of general claims, and 4 supporting claims for each of these. For example one general claim may be 'when it comes to security, ACE provides the best door locks.' One of the supporting claims would be 'the cylinders in ACE locks are more difficult to pick than any other lock.' Different claims were repeated to a different extent for each participant to remove any effects which may be due to the particular claim seen. They studied these and then saw the same 80 claims with an additional 30 filler claims after a break. They were told that they had seen some before and that some were new. They were also told that some were true and some were false, to make sure that just because they had seen some before did not mean they were true. For each claim the participant rated how true they thought it was and how familiar it was. Overall, the more times a claim was repeated during the study phase, the greater the belief the participant had in the claim. The biggest increase was after 1 repetition. Following this, each repetition did produce an increase in belief ratings, however the increase was smaller.

As we can see from this table, for each condition there is a general increase in the participants' belief in the claims after multiple repetitions. There are only two points were there is a decrease in belief ratings following a repetition. As a second repetition is added, the ratings decrease for both the 1 and 2 other claims conditions. However it wasn't stated whether this decrease was significant or not, and so we can still observe a general increase in ratings after more repetitions. 

The circled area of the table corresponds to the data which can be applied to this specific clip. Brick repeats his love for the lamp an extra two times, and this general claim is not supported by any other claims. The study did not state whether there was a significant difference in ratings between the number of other claims present. We can't therefore know whether if Brick had included some supporting claims in his persuasive message, whether this would have made his message more effective.

Overall, repetition has been found to help increase people's belief in a claim, and therefore make the claim more persuasive. 

Hawkins, S. A., Hoch, S. J., & Meyers-Levy, J. (2001). Low-involvement learning: Repetition and coherence in familiarity and belief. Journal of Consumer Psychology, 11, 1-11.