Faktory ovlivňující hodnocení vyhledávačů Search Engine Ranking Factors

Hodně rozporuplné

Poněkud rozporuplné

Průměrná shoda

Částečná shoda

Všeobecný souhlas

Tag <title> v HTML, který se obvykle ukazuje nahoře v okně prohlížeče a často také v SERP jako popisek webové stránky.

The sites and pages linked to from a document. These may positively or negatively influence rankings based on the quality of the links, their relationship to the linking document and any existing relationships between the sites hosting the documents.

Terms used on a page or in a query may be the same or only related by search engines. If a term is stemmed to its root form (i.e. financing & finance to financ) it could be that anchor text, queries, etc. containg that term would be equivalent & interchangeable.

These are structural signs that a piece of content is of great merit. Although we may not be aware of all the factors that fit into determining a document's quality through automated analysis, it is presumed by many that the major search engines have invested time and effort to find automated systems to measure a document's relative quality.

The use of text in alt tags and image tags is figured into the overall text in a document, although it probably does not undergo the scrutiny of body text in terms of quality, grammar, reading level, etc. Both of these tags are more commonly used for targeting image searches at the engines, along with the filenames of the images shown.

The relevant internal documents pointed to by a page may help to indicate to a search engine the subject of the page and the general subject of the content therein. Persitent navigation links (those in a menu or footer nav) will generally be ignored.

This factor will most likely be applied relative to the query entered so that sites in particular categories, such as humor, culture-specific, artistic and other areas where misspellings are intentional do not get filtered.

Reading level is typically calculated by measuring the words in a document and measuring their syllables or obscurity against wordlists from educational guidelines. Thus, complex documents might be considered to be at a 12th or 13th grade level (high school senior or college freshman in the US) while low-level, simplistic documents would be at a 5th or 6th grade reading level. A higher or lower level does not necessarily indicate a better result, but based on search terms, it could be more or less likely that a higher or lower reading level document would be preferable.

A website's primary topic (as determined through analysis of the content opf its hosted documents) may influence how well it is able to rank pages on similar, corresponding or off-topic subjects. If a site is particularly focused in one niche or another (from finance to politics to restaurants), documents hosted at that site on specific subjects encompassed by the broader topic may have a better chance of ranking well. There are also many sites on topics like news or general information distribution (e.g. CNN.com, Topix.net, etc.) that encompass all or many subjects equally and may be able to rank documents for a wide variety of topics.

Topical communities are measured by the search engines as groups of websites who interlink to and with one another frequently and carry a similar topic or theme. Since topical communities are relevant and "on-topic", the links from them carry great weight. A site that is included in a topical community by way of links from many other members may be considered more relevant and authoritative on the community's subject matter.

A site's internal link structure may influence the rankings of its pages by virtue of its organization. Search engines and visitors alike typically expect a persistent set of navigation elements as well as a hierarchy from broad subject matter to narrow. Sites exhibiting these types of linking structures may be rewarded with better rankings.

The links pointing to a document over time may be measured and have data extrapolated by the search engines to help the determine the legitimacy and value of new links. This may in turn affect the rankings of any documents hosted at the site, whether they are directly receiving external, inbound links or not.

The primary user-action in the SERPs would be a click-through to a search result. If a site receives a high click-through rate in the natural results and few searchers return to the engine immediately to select an alternate result or conduct a new search, the website and any hosted documents may benefit.

As links are found by the search engines pointing to a site and others that are removed disappear from the cached pages, data about link fluctuation, generation and dissipation can be stored in the search engines' repositories. This data may then be used to analyze future activity, make predictions, compare against other sites and find abnormalities. Sites that receive very few permanent links may be ranked lower than those whose links remain. Other websites where link stagnation is fast may be compared against others in the industry to see if this phenomenon is normal. All of these factors of link gain and loss over time may result in higher or lower rankings for hosted documents.

The size of a website as measured by the number of documents hosted on the site may raise or lower rankings depending on whether a search engine has a query-dependent or universal preference for larger/smaller sites.

A site's rankings(and its hosted documents') in the search results over time may be used by a search engine to influence ranking ability up or down over new documents or documents suddenly ranking much better than before. This is most often used in cases where large jumps in rankings over a short period are seen and the engine wants to investigate whether that jump was natural or the result of spamming, but other uses for the data are also possible.

"incestual" linking

There is speculation that some websites have gained the implicit trust of search engines. Educated guesses on their identities range from places like CNN.com to DMOZ.org to Whitehouse.gov, all in varying degrees, and all purely hypothetical, unknown in truth to all but a few engineers. Links from these sites may carry special weight and rank boosting power, although it will probably never be possible for SEOs to correctly identify or quantify them.

The extension of a site may impact the value of its links - .edu, .gov & .mil have all been surmised to carry stronger weight in their links than ordinary commercial documents (.com, .biz, .net, etc.).

If two websites link to one another's documents, subsequent links between the two or to a third party site which the other has already linked to may reduce the value of the link partially or fully.

Dostupnost dokumentu

Session variables can produce hazardous search rankings as duplicates of a URL's contents are indexed hundreds or thousands of times, diluting the incoming links and ranking power of the page as a stand-alone document.

Although difficult to detect, search engines finding evidence of IP-based content delivery on a website are likely to penalize or devalue that site in the results.

URL Hijacking includes the infamous use of 302 re-directs to assume control via the search results of a well listed domain. This issue can cause ranking issues over the short term for the hijacked site and long term potential problems for the hijacking site should the attempt be discovered.