Is everybody seeing DA/PA-drops after last MOZ-api update?

[NielsVos]

Hi all,

I was wondering what happend at the last MOZ-update. The MOZ-health page has no current errors and i've checked a lot of websites probably about 50 a 60 from our customers and from our competitiors and everybody seems to have a decrease in DA's / PA's. Not just a couple went up and down like normally would happen, but all seems to have dropped.... Is anyone seeing the same in their campaigns?

Greetings,
Niels

[Astute-Media]

Hi,

Yes i have just asked something similar. One client has seen a 10 point drop.Not an easy one to explain...

[Cannetastic]

Yep yep. I'm seeing drops across the board, for everyone!

[Astute-Media]

Anyone got more than 10!???

[Cannetastic]

Thankfully not, only between 1 and 3.

[NielsVos]

Yes, a new website we haven't worked on yet has dropped from 14 to 1. -.-

[Astute-Media]

Well, on the good side, there is only one way to go...

[ViviCa1]

Yep, the biggest drop we have seen is from 10 to 1 on a small website we haven't worked on in months. Mostly smaller drops but bigger than other months. I monitor some competitors as well and out of 24, 2 have stayed the same, 1 has improved, all others have dropped. Our websites have all dropped except for one (which has stayed the same).

Glad to know we're not the only ones!

[Cannetastic]

Are the websites you're all seeing drops on http or https?

The reason I ask is that I've seen a small drop on some http sites and a small rise on https sites. Wondering if there is a correlation?

[Astute-Media]

Our 10 point drop is on a https site

[Cannetastic]

Throws theory out of window

[ViviCa1]

Yeah, I can't see a pattern either. Most domains I track are still http including ours but the https ones I track have seen drops as well (4 out of 5, 1 has stayed the same).

[Astute-Media]

bounces theory of chest on to his knee, then volleys into the back of the non-existent net, and celebrates with Gillon the fact they have ruled something out

[Cannetastic]

Haha

[Hurf]

Yep. All HTTP. Drops of around 3 - 4 points across the board. It's almost reassuring that we're not alone.

[valdemarweb]

Dropped 3 points, so did all of our competitors. The number of links seemed to have taken a dive for all sites I follow.

Is anyone from Moz looking into this?

[Jan-Peter]

Any news around this topic yet?

We also dropped in Da from 29>27 and another of our sites even from 21>17 (both https). All of our competitors also dropped in DA (one 30>22).

No drops in rankings fortunately.

[Vertaalbureau_Perfect]

I'm also curious about any news/updates regarding this topic. So is there any news?

We suddenly dropped in DA from 40 > 34 (!) and our competitors lost a little less, from 3 to 5 DA points. We also lost like 185 external backlinks and so did our competitors.

Rankings are the same.

[tawnycase]

Hi there! Tawny from Moz's Help Team here.

Aw, man! Sorry to hear about your DA dropping. You're right that it appears to have happened for everyone, across the board.  I think I can help explain. The reasoning behind this can be hard to pinpoint without the help of an SEO consultant or the specific web designer for your website. Domain and Page Authority scores are both calculated using Moz's Ranking Models. In essence, we take a lot of rankings data from the search engines (by running queries) and then try to build a predictive scoring system using our own on-page analyses and Mozscape link data to construct an algorithm that will effectively reproduce the search engines' results. Our current accuracy hovers in the 70% range, but over time, we expect to improve.

Once we have a ranking model (which we internally call "uber"), we can create scores that best approximate the combinations of all our page-specific link metrics or domain-specific link metrics (removing the keyword-specific features like anchor text, on-page keyword usage, etc). These scores represent the model's query-independent or non-keyword-based ranking inputs.

In simple terms, Domain Authority is our best prediction about how content would perform in search engine rankings on one site vs. another. Page Authority answers the same question for an individual page. Both are amalgamations of all the link metrics (number of links, linking root domains, mozRank, mozTrust, etc.) we have into a single, predictive score.

It's important to note that both Domain Authority and Page Authority are on a 100-point, logarithmic scale. Thus, it's much more difficult to grow your score from 70 to 80 than it would be to grow from 20 to 30.

It is also important to note that if the higher authority sites that your site is seeded from drop in score, it will ripple down to all of the other links branched off from the very top. A good place to start is to compare the DA from the linking root domains from the previous index. Also take a look at your competitors scores to see how much they have dropped as well. As our indexes grow in size, there are more links that are included in our calculations. I think this is a big part of why we saw drops in Domain and Page Authority this time around - more links included in our calculations will skew the scores a bit lower.

We recommend keeping track of how many linking root domains you have from index to index, as this will be a quick way to confirm possible reasons for an increase/decrease in the score. For an in-depth discussion from Rand, check out this article: https://moz.com/community/q/da-pa-fluctuations-how-to-interpret-apply-understand-these-ml-based-scores I've found this article to be most helpful when I'm trying to determine why Domain or Page Authority scores may have fluctuated so much, especially when it's across the board like this.

Here's some places to really delve into what is going on: 
http://moz.com/blog/whiteboard-friday-domain-trust-authority 
http://moz.com/blog/googles-algorithm-pretty-charts-math-stuff 
http://moz.com/blog/whiteboard-friday-domain-authority-page-authority-metrics

Here are some good resources to help you take a look at the factors.
http://moz.com/blog/whiteboard-friday-domain-authority-page-authority-metrics
http://apiwiki.seomoz.org/w/page/20902104/Domain%20Authority
http://moz.com/blog/whiteboard-friday-domain-trust-authority

I hope this helps!

[SCL_Moz]

I also noticed that the number of External Links plummeted. Ours dropped from ~80 to ~45. Our biggest competitor lost about 150 of their 400.

Correct me if I'm wrong, but isn't this more likely to represent the Moz crawler not crawling certain URLs, rather than an actual loss of those backlinks?