Neighbourhood Pool Watch: Weekly network forecast 22nd July 2013

24th July, 2013

Last post

Important:
These posts are a test of the methods used to create the forecasts, and definitely do not forecast non-MTGOX US$ / BTC price related changes - for example the current massive decrease in the cost of a hash. Please do not use the forecasts here for financial forecasts - these posts might be useful in that respect.

0.Introduction
Ooops! I forgot to post this on Monday, my apologies. Although it's 24th July today, all data is from the week up until 0:00 UTC 22nd July as usual.

I'm still learning new forecasting methods, and it will be a while before I know enough to come up with a new forecasting method, and a while of testing after that.
Anyone interested in learning forecasting should probably start at Rob Hyndmans excellent textbook "Forecasting: principles and practice". It's a free online textbook, and doesn't expect a reader to have specialist knowledge. The textbook survives on donations, but they don't yet accept bitcoin.

1. Models and datasets:

The model datasets have been collected into one paste to save time. Model estimates have been likewise aggregated.

Forecast and canary model analysis

All datasets

All estimates

Canary model: An estimate of the current hashrate estimate based only on current price and previous network hashrates. Used to detect changes to the network caused by agents other than the direct action the MTGOX US$ / BTC price as determined by the model.

Models f1, f2, f3 and f4: These are the one, two, three and four week forecasts of the network hashrate, based on the modelled relationship between the MTGOX US$ / BTC and the network hashrate.

Difficulty modelling: Method one calculates a difficulty estimation using the network hashrate estimation and is recalculated each week. Method 2 calculates difficulty estimation based only on previous difficulties and the MTGOX price, and is only recalculated after each difficulty retarget.

2. Results

3. Charts

Chart 1:

A graphical history of the one, two, three and four week forecasts of the weekly average network hashrate compared to the actual network weekly average hashrate.

Chart 2:

A graphical history of the Canary model estimates of the weekly average network hashrate compared to the actual network weekly average hashrate.

Chart 3:

A graphical history of the last twenty six weeks of retarget date and difficulty estimates, actual retarget dates and actual difficulties. It should be noted that each retarget will often be forecast by two consecutive weekly forecasts, hence the multiple points per retarget on the new chart.

Chart 4:

A graphical history of the one, two, and three retarget forecasts of the Difficulty, modelled directly as a function of previous Difficulties and MTGOX US$ / BTC prices.