If you change your story, the probability of your guilt is 1.00. If one version of your story includes a false accusation (i.e., of another person), that goes up to 2.00

...and if your accusers are people who say things like the above, your probability of innocence is 10.00.

In all seriousness, you appear to be completely ignorant of the subject of coerced statements, as well as wildly overconfident about your ability to predict your own (not to mention other people's) behavior in highly abnormal situations. This, indeed, will make it difficult for you to understand the case for Knox and Sollecito's innocence.