The average test score of all students in a public school before the introduction of a new teaching method was 14. A researcher randomly selects a sample of 15 students from this public school after the introduction of the new teaching method and finds their test score to be 19.93. The standard error of the mean for these test scores is found to be 2.97. What is your conclusion on the introduction of the new teaching method (at 0.5 level of significance)?