Salton cosine: understanding this mathematical measure in SEO

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Salton Cosine

Salton's Cosine is an essential concept in SEO.

This method, also known as Cosine similaritycan be used to measure the semantic relevance between text documents and can be used to improve the optimisation of a website.

In this article, we will define this mathematical concept and its application in the world of SEO.

The Salton Cosine: a mathematical approach to assessing similarity

The Salton Cosine is named after Gérard Salton, a computer scientist renowned for his work on automatic text processing and information retrieval.

This researcher has developed this approach in order to quantify the similarity between two objects such as documents or vectors in an n-dimensional space. The Cosine measure consists of calculating the cosine of the angle formed by the vectors representing the objects under study.

If the Cosine is equal to 0, this means that the two objects under consideration are orthogonal and therefore unrelated.
If the Cosine is equal to 1, the two objects are perfectly aligned and have maximum similarity.
On the other hand, if the Cosine is equal to -1, this indicates that they are diametrically opposed.

Application of Salton's Cosine in natural referencing

When it comes to SEO, understanding and analysing semantic relevance is crucial to optimising a website. The Google algorithm considers content quality to be one of the main ranking criteria. So content that is relevant and rich in information on a given subject will rank higher in search results.

Creation of textual content

The Salton Cosine can be used to estimate the similarity between two pieces of textual content, such as web pages or newspaper articles. blog. Search engines use this type of mathematical measurement to determine whether a text is original enough compared to other existing sources. Content that is too similar to other online documents is likely to be penalised in terms of referencing, as it provides little added value to visitors and to the search engines themselves.

Website audits and analyses

The Salton Cosine can also be used during SEO audits to evaluate the thematic coherence of a website. By comparing the different sections of the site, as well as the keywords and expressions used, an approach based on this measurement makes it possible to assess whether the content as a whole is well aligned with the expectations of the target audience and the commercial objectives set.

How the Salton Cosine works: a deep dive into the method

To apply Salton's Cosine in SEO, it is necessary to follow a number of successive steps that will enable textual data to be analysed in mathematical form. These are as follows:

Text pre-processing: cleaning up documents, deleting irrelevant or too common words (stop-words), standardising terms (lower case, accents, etc.).
Vector representation of documents: each text will be transformed into a vector formed by the association of a word and its weight, often calculated using the method called TF-IDF (Term Frequency-Inverse Document Frequency). This weight represents the relative importance of the word in the document and across all the documents considered.
Calculation of the Salton Cosine: we then calculate the scalar product of the vectors of the two objects, divided by the product of the Euclidean norms of the two vectors.

The limits of Salton's Cosine

Although this mathematical approach is useful for evaluating the similarity between two textual contents, it nevertheless has certain limitations:

Sensitivity to changes in content : Two texts with different grammatical structures but dealing with the same subject can obtain a low measure of similarity according to Salton's Cosine.
Purely statistical analysis : This method only takes into account the quantitative aspects of texts (word frequency, weighting) and omits a large part of the semantic richness of a text (meaning of words, context, syntax).

Complementarity with other tools and methods

To overcome these limitations, we recommend using the Salton Cosine in conjunction with other SEO methods or tools.

For example, advanced semantic analysis using natural language processing (NLP) algorithms will make it possible to study the qualitative aspects of texts and refine the assessment of relevance.

In a nutshell, Salton's Cosine is a mathematical concept that helps quantify the level of similarity between two text documents, in particular to assess their relevance for natural referencing.

However, its limitations should be taken into account and it should be used in combination with other techniques to obtain a complete and reliable analysis of a website's SEO performance.