This seems like a poorly executed analysis of very interesting underlying data.
With this degree of average age variability they can't compare failure rates.
They should show us Kaplan-Meier (survival) curves not failure in this quarter.
Unless they set some datacenter on fire, not much in Q2 should be different vs Q1 for the same hard drive other than it being older.
Sure, internally, I'd do a better analysis controlled for age that shows if there are common failure rate increases but here they focus on model failure rates which is completely confounded by age differences.
I published the same criticism in relation to one of their earlier summaries. Backblaze responded with something along the lines of (paraphrasing liberally)
> We're giving you this data for free and providing a brief summary of what you should expect to see in it. We do not get paid to teach our readers advanced statistics, nor is that what we want to do. We encourage you to take the raw data and explain to people how you think it should be analysed.
which seems like a fair response. I'm very, very grateful that they release the data freely the way they do. It reflects well on them and more companies should do that.
croemer · · focus · HN ↗
With this degree of average age variability they can't compare failure rates.
They should show us Kaplan-Meier (survival) curves not failure in this quarter.
Unless they set some datacenter on fire, not much in Q2 should be different vs Q1 for the same hard drive other than it being older.
Sure, internally, I'd do a better analysis controlled for age that shows if there are common failure rate increases but here they focus on model failure rates which is completely confounded by age differences.
kqr · · focus · HN ↗
> We're giving you this data for free and providing a brief summary of what you should expect to see in it. We do not get paid to teach our readers advanced statistics, nor is that what we want to do. We encourage you to take the raw data and explain to people how you think it should be analysed.
which seems like a fair response. I'm very, very grateful that they release the data freely the way they do. It reflects well on them and more companies should do that.
croemer · · focus · HN ↗