EDIT: Since I wrote this post, IndiaFacts has very graciously published this on their portal here. I recommend reading that piece since it corrects some errors I made in this piece (such as using rasa when i meant svabhava) and it is a little clearer and uses precise sanskrit terms.
In part 1 I described the way to think of how events occur within reality. A brief summary is as follows: Every event that occurs can be modeled as a gaussian distribution. Succinctly, this means that at a particular point in time called the mean, the probability of that event occurring is the highest. At any other time (either before the mean or after it) the probability of this event drops. The way the probability is modeled it looks like a bell which is why GDs are often called bell curves. The “fatness” of a bell curve represents the variance of the GD which essentially models how uncertain that event is. If the GD had a small variance we are extremely certain that the event will occur around the mean value. If we were dead certain of when the event would occur the GD would degenerate into a single line in the graph and it’s variance would tend to 0. But enough of the math, why even choose such a symmetrical function to represent karma?
To answer this one needs to understand how causality works. The most important question here is: what affects you. There is actually a fairly long debate we could have about the definition of you but we shall leave it to our illustrious pitR s for they did it better than I could attempt today. We can say that generally the you is a combination of your experiences, your possible actions and your possible futures.
From the definition of the curves that I gave earlier you must have noticed that I am assigning seemingly arbitrary priors to each GD i.e their mean and variance. I noted that the mean and variance of these curves are fixed apriori, and by apriori I mean before you are even born. They are fixed by a hidden function which takes your past karma and computes the various (mean, variance) tuples and then assigns them to the distributions. So what about free will?
Long story short, it doesn’t exist. Free will is not a meaningful term because of the constraints imposed by a variety of factors such as and not limited to, one’s biology, one’s society and one’s religion. Does this imply that karma is deterministic? Must we now conclude, that since our priors are a function of past karma and are computed without our knowledge we are completely at the mercies of the gods in their wisdom.
No, and that’s why I used the GD rather than some other function. The GD models uncertainty. It allows for variability of the occurrence of the event. There is already randomness within any system so there is also randomness within the event’s occurrence and that is captured by the GD in it’s bell curve.
Even this however is a very narrow way to consider karma. This is because karma’s influence each other just as events influence each other in a Bayesian manner. For instance if we go back to our example of Rohan as @_Mauna_ pointed out, Rohan could simply disobey his mother; let us call it our event B. By definition it has a gaussian curve associated with it and here’s the kicker event A is influenced by event B and the priors for event A are actually assigned only after B is assigned. In this manner we can extrapolate backwards that the first couple priors that are assigned are the priors which govern our temperament: let us call these our innate rasa. After these rasa are assigned the interaction of the infant Rohan’s rasa with the external world moulds the rest of his priors and indeed molds the priors of whether he is going to listen to his mother or not.
If ponder on what this all really means, we can derive three separate types of karma:
This type of karma is related to the earlier discussed rasa found in each of us. The thoughts we have in our moments of solitude are a function of personal karma. Our tendency to overreact to situations is personal karma. Our ability to set aside negative thoughts and power through towards our goal (or lack thereof) are functions of our personal karma.
When we spoke earlier of event B affecting event A (both events specific to Rohan), it logically follows that any arbitrary event B affects any arbirtrary event A (even if the magnitude of the effect is negligible). Parallels to chaos theory or butterfly effect are not totally unwarranted but perhaps imprecise. All this aside it follows that event B occuring to a close family member affects the event A occuring to the individual in more signficiant way thant if it were to occur to any other person. Family karma is thus the effect of the karmas of the individuals within your family or more abstractly within your clan (where I will leave the definition of the term clan open ended on purpose). The things that affect them affect you more than any other individuals karma and thus it is a separate and distinct type of karma which plays a huge role in your well being. A very simplistic example is that of a horrible overbearing spouse whose personal karma is somewhat distatseful. Their karma directly affects your mental wellbeing and in some cases physical wellbeing. Perhaps this is why humans for millenia have engaed in arranged marriage practices, and not left such a difficult and important decision to the whims and fancies of their gullible and capricious children.
This is the final type of karma which can affect any individual. This could also be called transient karma since it’s effects are bound by both time and distance. For instance if you have a bad circle of friends your likelihood for engaging in delinquent behaviour increases in a bayesian manner. Perhaps this is why Indian mothers are so focused on fitting into a peer group with “good influence” since they natively understand that you will be moulded by the company you keep. Proximity karma changes as you age, because the company you keep changes as you age, but it significantly moulds the priors you will carry with you for life. 
Now that I have illustrated the different types of karmas that I have identified, one can perhaps see the value of modelling karma as a mutlivariate gaussian distribution. As I mentioned in the last post, believing in bayesian probability is equivalent to believing in karma. So what of free will, what of our predetermined future, what of the will of the gods?
I think we are best off taking one of the greatest lessons the Bhagvad Gita has to offer.
 The gene determinists among you can think of rasa as an abstraction of the genetic makeup
 I do not claim that this distinction is sufficient to describe karma, simply that it describes karma in an interactive world setting fairly well in my humblest of estimations
 As an aside if this reminds you of ta’veren you are not alone. I find the Wheel of Time to be extremely Hindu. After all the Dragon is reborn once every age to reset the Age and purge the world of Evil and bring back the Good. Who does that remind you of