How do SEM and 95% confidence interval help a scientist measure confidence in the mean? Answer on your answer sheet. Error bars are added in a +/- fashion to the mean in a graph and can be called confidence interval bars. What is the length of the bar telling you about your confidence in the mean value? Answer on your answer sheet. Scientists normally report either +/- 1SEM or +/- 95% CI bars to evaluate the mean. SEM bars bracket 68% of the variation while 95% CI brackets 95% of the variation The use of +/- 1 SEM is normally used in larger sample sizes while 95% CI is used as sample size decreases. Why do you think scientists report more standard error as sample size decreases? Answer on your answer sheet. In experiment 1, scientists are looking to see if the treated enzyme has a greater effect than the untreated control. Using the mean activity and +/- 1 SEM. Scientists claim that the treated enzyme shows greater activity than the control in this study. How would you use the mean and degree of error bar overlap to evaluate this claim? In experiment 2, another enzyme is used in comparison to the control. The scientists claim that the treated enzyme is not statistically different than the control and shows no effect. How would you use degree of error bar overlap to evaluate this claim?