First, consider deliberate thinking. Deliberate thinking is relatively slow, rule-based and explicit; a contemplative process of weighing pros and cons, gathering scientific or statistical evidence. It would appear that this makes for pretty solid decision-making.
Jul 24, 2015. Outliers increase the standard deviation. Mean is most affected by outliers, since all values in a sample are given the same weight when calculating mean. A value that is far removed from the mean is going to likely skew your results and increase the standard deviation. Say you have five values: 2, 1, 2, 1.5, and 2.1.
Then say you have five values: 2, 1, 2, 1.5, and 10. Your mean would be 3.3 and your standard deviation would be 3.77. That one outlier (10) makes your standard deviation much greater when compared to the earlier set of numbers. The effect would be less though if our sample size was larger and we only had one outlier.