Correction to my own post above:
30 USD is (probably, I didn't calculate it myself) the result of linear regression and, as I understood sarc, removing some outlier data (i.e. the bubbles).
The other charts I've seen that use the entire data have as at around 50 USD, IIRC.
Topic: Wall Observer BTC/USD - Bitcoin price movement tracking & discussion - page 33293. (Read 26498590 times)
June 05, 2013, 10:12:29 AM
June 05, 2013, 10:06:00 AM
Anyway, unless we start doing the mathematical part of this discussion in a more systematic fashion, I'm afraid we will keep misunderstanding each others' points.
I'm game for it. If you're looking at base notation, I seem to recall having used [for example] loge(x) and log10(x). Obviously, it is not standard notation but a compromise for a text-based medium.
I believe prof clarified things a little at one point and sarc continued to assert the incorrect thing as correct [ log(x+1) ].
Let one thing be said, though: whether sarc's graph or method was entirely accurate or not, the prediction "in the range of 30 USD" seems to be the one you get in fact, if you do a simple regression on the entire historical data.
This is not due to some massaging the data by sarc or a mistake in his method, but simply the result of that particular analysis. Whether that type of analysis is actually predictive of the future price is a different matter.
This is not due to some massaging the data by sarc or a mistake in his method, but simply the result of that particular analysis. Whether that type of analysis is actually predictive of the future price is a different matter.
No disagreement there. The exponent definitely changed. The question is whether it is a bubble or represents a different phase of Bitcoin's growth. I'm holding on to mine...
June 05, 2013, 10:05:49 AM
Haha. Cant even agree on Math.... long live the Wall Observer thread!
June 05, 2013, 10:04:49 AM
You are missing the point. A trendline is to best match the development of the price, and if it does match it is consistent and can be used as a model for an expectation.
One could even estimate the "offset" systematically to better match the graph and this would be as valid or even more valid than doing otherwise.
Oh, for sure. I just don't agree with "We add 1 because it's the correct thing to do".
June 05, 2013, 10:03:12 AM
@prof7bit
[...]
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
[...]
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
No. Adding a constant before taking the log of an exponential function distorts the curve. You would only add a constant if the exponential was starting from an offset (to counteract that offset).
If there is an offset in the bitcoin price (unlikely but possible), there is absolutely no reason to assume it is $1.
I never said you should add a constant to the value. I was talking about the equivalence of mapping to a log n and log n+1 chart. And that part is certainly true.
EDIT: I see the problem now. Damn sloppy notation :) you're talking about 'x', and I'm talking about base 'n' in log_(n)(x).
My point was, since the entire discussion between the two was sort of messy and unstructured, I'm not entirely sure what the claims of each party are, and I though at some point the two were arguing whether the above matters.
Anyway, unless we start doing the mathematical part of this discussion in a more systematic fashion, I'm afraid we will keep misunderstanding each others' points.
Let one thing be said, though: whether sarc's graph or method was entirely accurate or not, the prediction "in the range of 30 USD" seems to be the one you get in fact, if you do a simple regression on the entire historical data.
This is not due to some massaging the data by sarc or a mistake in his method, but simply the result of that particular analysis. Whether that type of analysis is actually predictive of the future price is a different matter.
June 05, 2013, 10:02:32 AM
June 05, 2013, 09:57:00 AM
@prof7bit
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
No. Adding a constant before taking the log of an exponential function distorts the curve. You would only add a constant if the exponential was starting from an offset (to counteract that offset).
If there is an offset in the bitcoin price (unlikely but possible), there is absolutely no reason to assume it is $1.
You are missing the point. A trendline is to best match the development of the price, and if it does match it is consistent and can be used as a model for an expectation.
One could even estimate the "offset" systematically to better match the graph and this would be as valid or even more valid than doing otherwise.
^yes.
June 05, 2013, 09:36:07 AM
@prof7bit
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
No. Adding a constant before taking the log of an exponential function distorts the curve. You would only add a constant if the exponential was starting from an offset (to counteract that offset).
If there is an offset in the bitcoin price (unlikely but possible), there is absolutely no reason to assume it is $1.
You are missing the point. A trendline is to best match the development of the price, and if it does match it is consistent and can be used as a model for an expectation.
One could even estimate the "offset" systematically to better match the graph and this would be as valid or even more valid than doing otherwise.
June 05, 2013, 09:29:31 AM
@prof7bit
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
I think he might be being facetious for a laugh...oh and to deny the need to sell his bitcoins.
Actually this is about if other people would consider selling them.
June 05, 2013, 09:26:38 AM
@prof7bit
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
No. Adding a constant before taking the log of an exponential function distorts the curve. You would only add a constant if the exponential was starting from an offset (to counteract that offset).
If there is an offset in the bitcoin price (unlikely but possible), there is absolutely no reason to assume it is $1.
June 05, 2013, 09:25:13 AM
@prof7bit
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
I think he might be being facetious for a laugh...oh and to deny the need to sell his bitcoins.
June 05, 2013, 09:23:48 AM
and then sell your bitcoins.
My bitcoins are none of your business. But you are free to do whatever you want with yours. You can even plot log(2 pi cos(price + $42)) or whatever else you want and also make sure to try different values of 42 (maybe 42 Yen or 42 EUR) until the chart looks like you want it to look and then base your trading decisions on it.
god, you're such a nerd.
Not that nerdy. You can't take cos of a value with units.
June 05, 2013, 09:22:00 AM
@prof7bit
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
Calm down, please. You're going as far as accusing sarc of posting false information on purpose, when all that goes on in reality is a disagreement about the math behind what was posted here.
My take on it (already mentioned above, shortened version to follow):
I don't know exactly what sarc did in his model, but if the dispute between you and him boils down to plotting the data on a chart with a log n y-axis vs. plotting the data on a chart with a log n+1 y-axis, then there is no dispute. The two are, for our purposes, equivalent.
If that's not the point of your dispute, I'm sorry that I missed it.
June 05, 2013, 09:19:01 AM
and then sell your bitcoins.
My bitcoins are none of your business. But you are free to do whatever you want with yours. You can even plot log(2 pi cos(price + $42)) or whatever else you want and also make sure to try different values of 42 (maybe 42 Yen or 42 EUR) until the chart looks like you want it to look and then base your trading decisions on it.
god, you're such a nerd.
June 05, 2013, 09:11:51 AM
and then sell your bitcoins.
My bitcoins are none of your business. But you are free to do whatever you want with yours. You can even plot log(2 pi cos(price + $42)) or whatever else you want and also make sure to try different values of 42 (maybe 42 Yen or 42 EUR) until the chart looks like you want it to look and then base your trading decisions on it.
June 05, 2013, 09:11:44 AM
To linearize things (make them 'straight' for analysis) that have points below and above 1, you add 1 to your log (i.e. log x+1).
No you dont!
You might have accidentally done log(x+1)
because log(x) +1 would not matter, it would only shift the entire graph up on the y axis while your log(x+1) totally distorts it.
not when it's logged. try it with numbers above and below 1.
I'm afraid I'm seeing prof7bit's side of things here.
Don't take my word for it, go grab your GCSE (or whatever) maths book.
y=exp(x)
x=log(y)
June 05, 2013, 09:11:29 AM
only that math cannot predict the bitcoin price of the future...
June 05, 2013, 09:03:43 AM
Don't take my word for it, go grab your GCSE (or whatever) maths book.
Yes, you should grab yourselfs a maths book and read it before you start posting nonsense plots of made up nonsense series agan. Good idea. Do it.and then sell your bitcoins.
June 05, 2013, 09:02:32 AM
June 05, 2013, 09:02:01 AM
Don't take my word for it, go grab your GCSE (or whatever) maths book.
Yes, you should grab yourselfs a maths book and read it before you start posting nonsense plots of made up nonsense series agan. Good idea. Do it. Jump to: