Hello jonnybravo0311,
Thanks for the detailed answer and reading my articles. I'll try to be as specific as possible.
1) "For example, whenever you're trying to predict an end-of-life scenario, or answer the question of, "how many BTC will this hardware mine?" how are you accounting for variable shifts in difficulty?"The variable shifts in difficulty are embedded into the model. The divisor of the equation is representing it, it has very little deviation mapping its variables; what I mean, it is that it accounts for the variability in difficulty. I've modeled the difficulty function before, but this model uses another data. My previous difficulty model was:
y = 8154638 + 0.00189782218745504*x^5 + 2.30690254039052*(10^-12)*x^8 - 659.311924843281*x - 3.39747197204999 (10^-6)*x^6
The problem with it, is that early on its not as precise as one would want. After some values, it gets more accurate. However, this model is not being used in the earnings function.
2) "Also, when you discuss profitability, how do you model the variance for BTC:fiat?"Sadly there's no modeling for BTC:fiat variance in the calculator. I might make a model for this, although I'll recommend to take with a grain of salt. The calculator is mostly a convenience, to save time in solving the equations in the article.
3) "The problem with every single online calculator and prediction engine is the assumption they inherently make with their calculations. Even your calculator at the bottom of your article does the same. It asks the user to input a value for BTC:USD. All of these models will fail simply because the conversion rate directly impacts the effect of electricity costs, and thus the longevity of the hardware. "Yes, you're right. Without a model for the BTC:fiat variance, sadly, that's the easiest thing to do.
4) "Cloud mining contracts come in two basic flavors: the fixed rate contract and the variable maintenance-fee contract. "I didn't know this. Interesting.
5) "Further, the results you obtain from online calculators must be taken with a grain of salt because at best they are semi-educated guesses."You're right again. 100% agree.
Perhaps I'll have to improve the explanation of what my AI does in my website, but I'll try to shed some light on it.
What I do when I use my AI, is giving it my data, and asking it what kind of model should it find, like f(x) = earnings(day). To create the models in the articles, I just asked the AI to map income per GHS per day to the amounts I was accumulating, in so doing it figured out several models which have different margins of error; what I do is pick the one which I feel most clearly represents the situation. Sometimes the most relevant formula has a higher margin of error than others, which has very likely been a result of overfitting in the other equations.
Again, thank you very much for your detailed answer. And if you have insider knowledge on mining, I would very much like to pick your brain if you don't mind.
And if it serves as a disclaimer of sorts, I barely do bitcoin mining; I'm much more interested in the math of it. This is so cool and innovative.