Open veeral-patel opened 4 years ago
A $0 loss isn't really a loss, and in any case the lognormal can't capture a 0 low loss accurately (it can't deal well with large high loss/low loss ratios).
Instead when I am eliciting low/high loss values I describe them like this:
In the low loss scenario, imagine everything goes well (other than that a loss occurred)--detection systems worked, we noticed the alarm as soon as is feasible, we stopped further loss, and recovered quickly. A 5th percentile makes sense by that description, because we might become extraordinarily lucky and have an even lower loss than described.
In the high loss scenario, imagine everything goes wrong--we don't detect the loss, and it continues basically as long as it can, up to and including losing all the data. Here a 95th percentile can still make sense because things can always become worse, for example high publicity around the loss, litigation, regulatory fines, etc. beyond what we might expect.
@mdeshon thanks for your reply!
detection systems worked, we noticed the alarm as soon as is feasible, we stopped further loss, and recovered quickly
The way I'm thinking about it is that the loss is correlated with the amount of customer data lost. In the low loss scenario, a "small amount" of customer data is lost, but that feels arbitrary to me.
Should I say 1% of data was stolen for low loss? 5%? 20%?
High loss is easier for me. I just compute the cost of losing the data itself, plus secondary costs like regulatory fines, litigation, loss of employee productivity, hiring forensics firms, etc. It's a reasonable worst case scenario...am I thinking about this right?
@mdeshon wanted to follow up!
Let's take an example of Alice stealing our company's customer data, which is worth $1M to us.
Intuitively, the low loss is that she fails to take any data ($0) and the high loss is that she steals all the data ($1M).
Am I choosing the low loss and high loss correctly here? Also, I read that the low loss and high loss should create a 90% confidence interval...how does that apply here?