A randomized study compared two different techniques for improving one's memory. The treatment group using Technique A reported that the subjects were able to memorize a mean of 8.9 words. The treatment group using Technique B reported that the subjects were able to memorize a mean of 12.1 words. To determine if the results are significant, the data are re-randomized and the differences of the means are shown in the dot plot. What is the best conclusion to make based on the data?