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

[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?

[tawnycase]

You're not wrong! Seeing a drop in links is likely to mean that our crawlers just didn't pick up those URLs this time around and include them in our index, but in all likelihood those links that we previously reported are still out there on the web. Our tools just haven't re-visited them to add them back into the index.

[NielsVos]

Are you guys seriously using templates to answer questions about a lower DA. -.- ? I've got the exact same answer in the chat...-.- Atleast you could admit something went wrong with the last API-update.... As i'm counting the people here... more then 13 seo-consultants who pay a lot of money per month for accurate tracking all dropped down with a lot of websites.

Normally i wouldn't bother with a dropdown and it will probably be fixed in the next update but some customers even use it as a KPI and we gotta explain them we worked hard but they dropped with 10 points. -.- So answering something like:

"The reasoning behind this can be hard to pinpoint without the help of an SEO consultant or the specific web designer for your website".

Ain't gonna cut it for me..-.- What do you think we are? Atleast give us something we can communicate to our customers. -.- What i see in the API is a loss of:

• Januari 2017 » 1,100,261,648,691 (1.1 trillion) links.
• December 2016 » 1,114,899,547,461 (1.1 trillion) links.

So i could see it as a loss of 14 billion links since the last update? And because those links where lost for all high DA-websites everything dropped down. That would be the answer i aspected.
No hard feelings, but just be transparant with us, so we can communicate it to our customers.

[Cannetastic]

I second that.

[randfish]

Hi Niels - yep, I saw a bit of this too. I believe there's two causes:

1. We crawled a larger swath of the web in this index, so we captured more sites and more links, and that may mean the scaling of PA/DA (which are logarithmic) stretches to accommodate the larger number of links found, especially to sites at the top of the scale. For example, if Facebook has a DA of 100 with 5 Billion links, then we find 5 billion more links to it, Facebook still has a DA of 100, but it's a much higher threshold. Thus, sites with fewer links (and less quality links) will fall in DA as the scale is now stretched.

2. We crawled some weird stuff in this index, by mistake (or rather, because spammers built some nasty, deep crawl holes that Google probably didn't fall for but we did). A ton of odd domains on strange ccTLDs were seen, and crawled, because they gamed PageRank with lots of sketchy links. We've now excluded these for indices going forward, and hopefully will see the impact abate.

All that said, over time, as our index grows, you can expect that raw DA/PA numbers could get harder to achieve, meaning a lot of sites will drop in PA/DA (and some will grow too, as we discover more links to them in the broader web). My best advice is always to not use PA/DA as absolutes, but rather relative scores. That's how they're designed and how they work best.

It's like back when Google had PageRank, and Moz.com grew from PR4 to PR7, then as Google got bigger and bigger, and the web got bigger, Moz.com fell to PR5, even though we had way more links and ranked for way more stuff. The raw PR scale had just become stretched, so our PageRank fell, even though we'd been improving.

[therealfudgypup]

Yeah all my own and client sites are down 2-4 points.  I'm seeing a decline in backlinks tracked so I thought that may be a factor.  It's either a one time change moving forward or perhaps a bug that will correct itself next week?  No idea.