Neighbourhood Pool Watch: Weekly network forecast 17th June 2013

17th June, 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.

Errata: I hadn't realised that bitcoincharts.com had changed the way their API worked and I was only pulling part of the week's data. I now pull the data directly from MTGOX.

This undoubtedly has had an effect on the accuracy of the estimates for recent weeks, but probably not much of one. The method 2 difficulty modelling has been back calculated to include the new data, but I can't do the same for method 1 difficulty modelling or network hashrate modelling. This means that the historical method 2 estimates will be slightly different but the other estimates will not.

0.Introduction

The network hashrate increase is slowing a little - a 12 Thps increase in the weekly average network hashrate from the 10th to 17th June 3rd June. The Canary Model plot indicates these are unlikely to have been influenced by the recent MTGOX BTC price changes - ASICMiner solomining and their high priced Blades, and the onset of the Batch two deliveries.

The "peakiness" of the MTGOX BTC price-unrelated hashrate changes are a real problem for the models. Not only is the hashrate partially uncoupled from the price, but the rapid changes and plateaus make the hashrate and difficulty very hard to model - it's clear that the two three and four week forecasts will be inaccurate, and the method 2 Difficulty modelling will also be inaccurate.

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.