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Readability

Lix Readability Formula

The Lix Reading Formula has become extremely useful for application in several non-English languages, being used for both English and non-English texts. You might have heard of the Rix Reading Formula before. The Lix is much the same as the Rix and assesses reading skills and readability of texts. 

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Introduction

Our text compare tool is a fantastic, lightweight tool that provides plagiarism checks between two documents. Whether you are a student, blogger or publisher, this tool offers a great solution to detect and compare similarities between any two pieces of text. In this article, I will discuss the different ways to use the tool, the primary features of the tool and who this tool is for. There is an FAQ at the bottom if you run into any issues when trying to use the tool.

What makes Originality.ai’s text comparison tool stand out?

Keyword density helper – This tool comes with a built-in keyword density helper in some ways similar to the likes of SurferSEO or MarketMuse the difference being, ours is free! This feature shows the user the frequency of single or two word keywords in a document, meaning you can easily compare an article you have written against a competitor to see the major differences in keyword densities. This is especially useful for SEO’s who are looking to optimize their blog content for search engines and improve the blog’s visibility.

Ways to compare

File compare – Text comparison between files is a breeze with our tool. Simply select the files you would like to compare, hit “Upload” and our tool will automatically insert the content into the text area, then simply hit “Compare” and let our tool show you where the differences in the text are. By uploading a file, you can still check the keyword density in your content.

URL compare

Comparing text between URLs is effortless with our tool. Simply paste the URL you would like to get the content from (in our example we use a fantastic blog post by Sherice Jacob found here) hit “Submit URL” and our tool will automatically retrieve the contents of the page and paste it into the text area, then simply click “Compare” and let our tool highlight the difference between the URLs. This feature is especially useful for checking keyword density between pages!

Simple text compare

You can also easily compare text by copying and pasting it into each field, as demonstrated below.

Features of Originality.ai’s Text Compare Tool

Ease of use

Our text compare tool is created with the user in mind, it is designed to be accessible to everyone. Our tool allows users to upload files or enter a URL to extract text, this along with the lightweight design ensures a seamless experience. The interface is simple and straightforward, making it easy for users to compare text and detect the diff.

Multiple text file format support

Our tool provides support for a variety of different text files and microsoft word formats including pdf file, .docx, .odt, .doc, and .txt, giving users the ability to compare text from different sources with ease. This makes it a great solution for students, bloggers, and publishers who are looking for file comparison in different formats.

Protects intellectual property

Our text comparison tool helps you protect your intellectual property and helps prevent plagiarism. This tool provides an accurate comparison of texts, making it easy to ensure that your work is original and not copied from other sources. Our tool is a valuable resource for anyone looking to maintain the originality of their content.

User Data Privacy

Our text compare tool is secure and protects user data privacy. No data is ever saved to the tool, the users’ text is only scanned and pasted into the tool’s text area. This makes certain that users can use our tool with confidence, knowing their data is safe and secure.

Compatibility

Our text comparison tool is designed to work seamlessly across all size devices, ensuring maximum compatibility no matter your screen size. Whether you are using a large desktop monitor, a small laptop, a tablet or a smartphone, this tool adjusts to your screen size. This means that users can compare texts and detect the diff anywhere without the need for specialized hardware or software. This level of accessibility makes it an ideal solution for students or bloggers who value the originality of their work and need to compare text online anywhere at any time.

What does the Lix do?

It measures readability levels by counting the number of letters in a text. It doesn’t count syllables like other formulas do because syllable counting can be inaccurate if you are using non-English languages. Instead, both the Lix Reading Formula and the Rix use the letter counting method. 

Where did the Lix Formula come from?

The Lix Reading Formula comes from Sweden. A man by the name of Carl-Hugo Björnsson created it in 1968. He published the results in a book called Läsbarhetsindex. If you translate that into English, it means ‘readability.’ Carl-Hugo Björnsson called it ‘Lix’ for short.

What Björnsson did to ensure accuracy in his reading formula

Björnsson kept 162 books which he used to rate readability features. Teachers and student groups used his readability content. These 162 texts consisted of fiction, textbooks, and technical literature. You can see he had a large range of literature available to the teachers and students.

He would compare text features to measure the readability of a text

He would look at the complexity of the text, the length of sentences, unusual words, and different words to assess its level of readability. He would eliminate anything that wasn’t consistently accurate with all readability formulas. There were other readability assessments that counted syllables and unfamiliar words.

Lix is used to calculate the percentage of words with seven or more letters. It is quite similar to other formulas such as the Flesch-Kincaid Readability Score Formula, Spache Formula, and Fry Formula. It calculates the average number of words in a sentence.

Check out a description of the Lix Formula here:

Lix is the percentage of long words plus the average number of words in a sentence.

It was shown that Lix had a high level of accuracy

Jonathan Anderson created the Rix Formula ten years after the Lix Reading Formula was developed. Anderson wanted to take the Lix formula to a grade level because he realized that many librarians and teachers used the grade level. He modified the formula, creating the Rix Reading Formula.

The criteria he used were revealed in a reading study by RM Thorndike in 1973. Anderson tested Lix, using the same texts from the study by RM Thorndike. In a second study, he discovered that the Lix Reading Formula showed a high level of accuracy as a readability test.

Because Anderson was satisfied with his results after testing the accuracy of Lix’s readability assessments, he made a conversion table. Here it is, available in Readable.

The usefulness of Lix

The formula is a simple measure that is useful for determining the readability score of a text. It's used for educational purposes and has been found reliable for detecting reading levels for many ages, from young kids to adults. The Lix is also a valuable formula for categorizing books.

For readability in a few non-English languages, Lix was also studied. One of these studies focused on Lix being used for languages such as German, French, English, and Greek.

To compute Lix scores, these are the steps

  1. Count the total number of words as well as the number of long words that have more than six letters. Also, count the number of sentences in the text.
  2. Then calculate the percentage of long words in the text.
  3. Next, calculate the average words in the sentence.
  4. Add the amounts you come to in Steps 2 and 3 and round them to the closest whole number.

The scores obtained will range from around 20, which is very easy, to around 60, which is very difficult.

The Lix Formula is easy to use for calculation and for examining text at different levels, from small children’s materials to secondary levels and adults’ text.

Lix proved an excellent solution for foreign language readability

Lix used to be a little-known readability index that was only popular in Scandinavia, but now it’s popular all over the world.

  1. Nelson commented on the computation of the Lix like this:


"Lix is not only simple to calculate, avoiding as it does, mathematical formulae, it differs from the English readability measures in two important ways. Firstly, it bypasses the problem of whether to count monosyllabic words, polysyllabic words or total syllables by including only words beyond a certain length; that it is a measure which ignores the linguistic rules of syllabification suggests that it is potentially useful across languages. Secondly, Lix calculates the percentage of long words from 100 word samples while sentence length is computed from separate 10- sentence samples."

The comparisons of French and English Texts with Lix

The French Lix indices correlated 0.87 with Lix indices in English. Flesch indices across languages correlated 0.90. Both of these varying correlations suggest that the French and English formulas were very similar. Using Lix and Flesch for French books, the correlation was -0.80. For the English books, it was -0.78. The results are negative because difficulty is rated high on Lix, and low on the Flesch.

Factors that contribute to making reading difficult

o Factors concerning the reader.

o The purpose of why the text was written.

o How readers ‘read’ the text and interact with it.

Lix, like the other readability measures, only provides incomplete and inexact estimates of reading difficulty with its readability scores.


Björnsson provided this table of readability categories to interpret readability test scores for Lix. The norms are for the Swedish language. You can only interpret Lix scores in the Greek, French, and German languages.

Conclusion

"Lasbarhetsindex" or Lix is a readability formula that was developed in Sweden. It appears to be able to assess text difficulty in other languages too, including English.

For documents in Western European languages, the Lix formula is useful as a readability analysis tool. It bases itself on sentence length and the number of long words. Long words are words that have over six characters in them.

All Readability Tests:

Here is a list of all readability tests.

Jonathan Gillham

Founder / CEO of Originality.ai I have been involved in the SEO and Content Marketing world for over a decade. My career started with a portfolio of content sites, recently I sold 2 content marketing agencies and I am the Co-Founder of MotionInvest.com, the leading place to buy and sell content websites. Through these experiences I understand what web publishers need when it comes to verifying content is original. I am not For or Against AI content, I think it has a place in everyones content strategy. However, I believe you as the publisher should be the one making the decision on when to use AI content. Our Originality checking tool has been built with serious web publishers in mind!

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Frequently Asked Questions

Why is it important to check for plagiarism?

Tools for conducting a plagiarism check between two documents online are important as it helps to ensure the originality and authenticity of written work. Plagiarism undermines the value of professional and educational institutions, as well as the integrity of the authors who write articles. By checking for plagiarism, you can ensure the work that you produce is original or properly attributed to the original author. This helps prevent the distribution of copied and misrepresented information.

What is Text Comparison?

Text comparison is the process of taking two or more pieces of text and comparing them to see if there are any similarities, differences and/or plagiarism. The objective of a text comparison is to see if one of the texts has been copied or paraphrased from another text. This text compare tool for plagiarism check between two documents has been built to help you streamline that process by finding the discrepancies with ease.

How do Text Comparison Tools Work?

Text comparison tools work by analyzing and comparing the contents of two or more text documents to find similarities and differences between them. This is typically done by breaking the texts down into smaller units such as sentences or phrases, and then calculating a similarity score based on the number of identical or nearly identical units. The comparison may be based on the exact wording of the text, or it may take into account synonyms and other variations in language. The results of the comparison are usually presented in the form of a report or visual representation, highlighting the similarities and differences between the texts.

String comparison is a fundamental operation in text comparison tools that involves comparing two sequences of characters to determine if they are identical or not. This comparison can be done at the character level or at a higher level, such as the word or sentence level.

The most basic form of string comparison is the equality test, where the two strings are compared character by character and a Boolean result indicating whether they are equal or not is returned. More sophisticated string comparison algorithms use heuristics and statistical models to determine the similarity between two strings, even if they are not exactly the same. These algorithms often use techniques such as edit distance, which measures the minimum number of operations (such as insertions, deletions, and substitutions) required to transform one string into another.

Another common technique for string comparison is n-gram analysis, where the strings are divided into overlapping sequences of characters (n-grams) and the frequency of each n-gram is compared between the two strings. This allows for a more nuanced comparison that takes into account partial similarities, rather than just exact matches.

String comparison is a crucial component of text comparison tools, as it forms the basis for determining the similarities and differences between texts. The results of the string comparison can then be used to generate a report or visual representation of the similarities and differences between the texts.

What is Syntax Highlighting?

Syntax highlighting is a feature of text editors and integrated development environments (IDEs) that helps to visually distinguish different elements of a code or markup language. It does this by coloring different elements of the code, such as keywords, variables, functions, and operators, based on a predefined set of rules.

The purpose of syntax highlighting is to make the code easier to read and understand, by drawing attention to the different elements and their structure. For example, keywords may be colored in a different hue to emphasize their importance, while comments or strings may be colored differently to distinguish them from the code itself. This helps to make the code more readable, reducing the cognitive load of the reader and making it easier to identify potential syntax errors.

How Can I Conduct a Plagiarism Check between Two Documents Online?

With our tool it’s easy, just enter or upload some text, click on the button “Compare text” and the tool will automatically display the diff between the two texts.

What Are the Benefits of Using a Text Compare Tool?

Using text comparison tools is much easier, more efficient, and more reliable than proofreading a piece of text by hand. Eliminate the risk of human error by using a tool to detect and display the text difference within seconds.

What Files Can You Inspect with This Text Compare Tool?

We have support for the file extensions .pdf, .docx, .odt, .doc and .txt. You can also enter your text or copy and paste text to compare.

Will My Data Be Shared?

There is never any data saved by the tool, when you hit “Upload” we are just scanning the text and pasting it into our text area so with our text compare tool, no data ever enters our servers.

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