Are there any statistically valid studies on:

How many survivor's stories include the line,"I had given up hope ...."

How many survivor's stories include the line,"Just as I was giving up hope ...."

How many survivor's stories include the line,"I never gave up hope ...."



How do you correct the statistics for those who never gave up hope but did not survive?

How do you correct the statistics to remove your own bias about the attitudes, if any, necessary to survive?