Talk:Morale/Fatigue/@comment-24269960-20140503071717/@comment-61.127.97.155-20140509045029

You use two tailed test when you are unsure what difference you are testing to see. The general speculation is line abreast is evasive and so the alternative hypothesis to test is unarguably "line abreast increases evasion". Besides, in such a case you generally would use the 5% SI

I'm not sure how the 'cumulative probability' has become 0.458 and is not 0.39. What are you cumulating?