Vienna Formula for Technical Texts

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The Vienna Formula for Technical Texts is used to calculate the readability of German-language texts. It indicates which school grade level a non-fiction text is suitable for. The scale starts at grade 4 and ends at 15, with levels above 12 being considered more as difficulty levels rather than school grades.

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How the Wiener Sachtextformel Works

The Wiener Sachtextformel (Vienna Formula for Technical Texts) was developed by Richard Bamberger and Erich Vanecek to calculate the readability of German-language texts. It provides an indication of which school grade level a non-fiction text is suitable for.

The formula uses the following variables:
MS = Percentage of words with three or more syllables
SL = Average sentence length (number of words)
IW = Percentage of words with more than six letters
ES = Percentage of one-syllable words

There are four variants of the Wiener Sachtextformel:

WSTF1 = 0.1935 * MS + 0.1672 * SL + 0.1297 * IW - 0.0327 * ES - 0.875 WSTF2 = 0.2007 * MS + 0.1682 * SL + 0.1373 * IW - 2.779 WSTF3 = 0.2963 * MS + 0.1905 * SL - 1.1144 WSTF4 = 0.2744 * MS + 0.2656 * SL - 1.693

The scale starts at grade 4 and ends at 15, with levels above 12 being considered more as difficulty levels rather than school grades. A value of 4 represents a very easy text, while 15 indicates a very difficult text.

Interpretation of scores:
4-5: Very easy text, suitable for 4th-5th grade
6-7: Easy text, suitable for 6th-7th grade
8-10: Average text, suitable for 8th-10th grade
11-12: Difficult text, suitable for 11th-12th grade
13-15: Very difficult text, suitable for college level and above

The Wiener Sachtextformel is particularly useful for assessing German non-fiction texts, technical documents, and educational materials. It helps ensure that texts are appropriate for their intended audience, supporting better comprehension and learning outcomes.