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Showing posts from May, 2016

Survival analysis of hard disk drive failure data: Update to Q1 2016

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Ross Lazarus, May 2016This is an update to http://bioinformare.blogspot.com.au/2016/02/survival-analysis-of-hard-disk-drive.html now that additional data for Q1 2016 has been released from https://www.backblaze.com/b2/hard-drive-test-data.html.
I reran my scripts and got the plots shown below. Whole process only takes a few minutes.

For me, the interesting thing is that so little really changes in the KM curves and statistics with 10% more data, suggesting that this statistical approach is reliable and robust, although in general we expect that more data provides better resolution. 

The WD30-EFRX and WD10-EADS and drives are reordered in terms of failure risk with more data down near the middle of the pack, but the updated models KM curves otherwise suggest the same pattern of risk of failure over time. Hitachi and HGST have reversed their positions at the top of the manufacturer survival curves as a result of the additional data, but the other manufacturers remain largely unchanged.

In t…