9. Troubleshooting and adjustment. In your first few years as a search optimizer, you’ll almost certainly run into the same problems and challenges everyone else does; your rankings will plateau, you’ll find duplicate content on your site, and you’ll probably see significant ranking volatility. You’ll need to know how to diagnose and address these problems if you don’t want them to bring down the effectiveness of your campaign.
Moreover, the PageRank mechanism is entirely general, so it can applied to any graph or network in any field. Currently, the PR formula is used in bibliometrics, social and information network analysis, and for link prediction and recommendation. It's even used for system analysis of road networks, as well as biology, chemistry, neuroscience, and physics. 

The first component of Google's trust has to do with age. Age is more than a number. But it's not just the age when you first registered your website. The indexed age has to do with two factors: i) the date that Google originally found your website, and; ii) what happened between the time that Google found your website and the present moment in time.
SEO experts have a really bad habit: They like to throw around strange words and industry jargon when they talk to customers without checking to make sure that their clients understand the topic at hand. Some do this intentionally to paper over the fact that they use black hat techniques that will ultimately hurt their customers. But for most, it’s simply a matter of failing to recognize that part of their job is to educate their clients.
On another note, I would like to express my contempt for Google and its so called terms of service regarding the legitimate acquisition of links. why should it care if links are paid for or not? Thanks to the invention of pagerank, it is Google itself that has cancelled out reciprocal linking and has stopped people giving out links due to fear of them losing pagerank, and blogs and forums are worthless thanks to the nofollow trick. so it is now impossible to get decent links organically, without having to pay for them, and those who do give out free links are considered fools. Google has brought this dilemma on itself, and yet it seems like punishing us for trying to get links other than freely! Face facts, no one is going to link to someone without getting a link in return! google has invented pagerank which is like a currency, and so people expect to be paid for links, as giving out links devalues their pagerank and so compensation is now required. It is forcing people to use underhand methods to get links, mostly the ‘paid’ variety.

In both versions of my model, I used the total of my initia esitimate to check my math was not doing south. After every iteration, the total Pagerank remains the same. This means that PageRank doesn’t leak! 301 redirects cannot just bleed PageRank, otherwise the algorithm might not remain stable. On a similar note, pages with zero outbound links can’t be “fixed” by dividing by something other than zero. They do need to be fixed, but not by diluing the overall PageRank. I can maybe look at these cases in more depth if there is some demand.
Links still matter as part of the algorithmic secret sauce. The influence of a site’s link profile is plain to see in its search engine rankings, whether for better or worse, and changes in that link profile cause noticeable movement up or down the SERP. An SEO’s emphasis today should be on attracting links to quality content naturally, not building them en masse. (For more on proper link building today, see http://bit.ly/1XIm3vf )
“So what happens when you have a page with “ten PageRank points” and ten outgoing links, and five of those links are nofollowed? Let’s leave aside the decay factor to focus on the core part of the question. Originally, the five links without nofollow would have flowed two points of PageRank each (in essence, the nofollowed links didn’t count toward the denominator when dividing PageRank by the outdegree of the page). More than a year ago, Google changed how the PageRank flows so that the five links without nofollow would flow one point of PageRank each.”
Site owners are using the toolbar to find “good” sites that they should get links from, regardless of the fact that link context is also important, not to mention many, many other factors that are used by Google to rank a web page. Other site owners, getting a gray PR0 toolbar for their site, immediate assume the worst, that they’ve been blacklisted.
As a webmaster or business owner, you're going to get a plethora of emails or form submissions offering things like guest posting services, backlink building offers, offers to buy domains with a "high page rank" and whatnot - like the one right here I got just today. Don't entertain them! It's tempting to think that hey, "I can pay someone to build more backlinks to my website and reap the fruits of their labors... mwahaha" but 99% of those services are more trouble than they'll ever be worth. Why?
Due to the importance of backlinks, there are lots of bad practices followed by website owners to gain backlinks. Some of these bad practices are: purchasing backlinks, link exchange networks, selling backlinks, etc. Most of these practices are not recommended by search engines. They usually deindex and penalize websites suspected of involvement in such practices.
However, if you're going to understand online marketing, you have to understand the importance of building Google's trust. There are three core components involved here. These three core components are like the pillars of trust that comprise all of Google's 200+ ranking factor rules. Each of those rules can be categorized and cataloged into one of these three pillars of trust. If you want to rank on the first page or in the first spot, you need to focus on all three, and not just one or two out of three.
If you don’t want to rebuild an expired domain, just take its backlinks and allow the linkers to be aware of the “to-dead-resource” linking. You can ask a link-builder to replace non-working links with your website’s one. If the content is relevant, you can try to restore it. Be sure that you can make it better than it was before. Reach out and inform the link-builder about the renewed content.
My main concern though, is Google appears to becoming reliant on sites doing MANY things for SE only. It also appears that Google is lowering the bar for YouTube videos in the organic SERPs and forcing their insertion as the cost of relevant pages. It even seems they are now doing the same for pictures, despite BOTH having their own SEs. I fear Google is attempting to increase profits, for it’s shareholders, in a rather impatient manner.

The SEO starter guide describes much of what your SEO will do for you. Although you don't need to know this guide well yourself if you're hiring a professional to do the work for you, it is useful to be familiar with these techniques, so that you can be aware if an SEO wants to use a technique that is not recommended or, worse, strongly discouraged.
Ask for a technical and search audit for your site to learn what they think needs to be done, why, and what the expected outcome should be. You'll probably have to pay for this. You will probably have to give them read-only access to your site on Search Console. (At this stage, don't grant them write access.) Your prospective SEO should be able to give you realistic estimates of improvement, and an estimate of the work involved. If they guarantee you that their changes will give you first place in search results, find someone else.
Such an enlightening post! Thanks for revealing those sources, Brian. This really has opened up my mind to the new ideas. I have read many articles about SEO, especially the ones in my country, most of them don’t really tell how to increase your presence in search engines. But today I found this page, which gave me much more valuable insights. Definitely going to try your tips.. 

Denver Colorado Internet Marketing