Domain Authority

[DaveMiddleton]

This latest report from MOz shows our DA dropping 2 points. I do not see anything that would have caused that? I saw on June 21st Moz wasn't reporting DA is this a Moz issue or should I dig deeper into my website?

[KristinaKeyser]

Hi Paula - Kristina from Moz's Help Team here.

Sorry to hear about your DA dropping. 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.

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

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

As always, you can contact our team in the future on questions about metrics or tool-specifics by shooting us an email at help@moz.com, but I hope this helps!

Thank you,
-Kristina

[elsenorglobo]

Hello,

I think if you Moz your DA reduced by 2 points, there is some reason. It can happen for example that you have not changed anything from the web but some page url low reputation without your doing has bound you, it appears in some form or spam for something your domain on your page and until it is removed naturally will be penalized eyes of the robot.

[Deacyde]

I'd also check to make sure all backlinks are still present and accounted for, or see if you have plus or negative backlinks from moz here.

If for some reason their index didn't get as many of your backlinks as it had before, you'd DA will be lowered. Now I don't think this is very fair nor accurate for smaller sites, since unless your a huge site, you will not get all your backlinks crawled, so you won't get a complete picture of your DA nor the Backlink profile, infact, only google holds the keys to all your backlinks and even they could use some work in how they are listed to us.

Just remember, backlinks play a HUGE part of the SEO game, when in doubt, check backlinks.

[SilverStar1]

Funny enough our site dropped by 4 positions also, and we got the exact word for word answer as Kristina used there?

[DaveMiddleton]

Yes, I was checking other sites (not ours) and it seems to be across the board DA dropped.