Calculating the 'fog factor' in writing

[Jim Brown]

There's a way of meaasuring the complexity of writing called the 'fog factor'. It's based on some calculation based on sentence length in a sample, as well as the number of polysyllabic words. But I seem to think there are other rules, like 'higher' is derived from 'high' so doesn't count as 2 syllables. Or something like that anyway.

As far as I remember, the factor is an indication of the number of years formal schooling the reader would need to be able to cope with the work; so 12 would mean high-school, 15-16 a B degree etc.

I wondered if anyone had come across an automatic tool for doing the calc: type or scan some text in, and Voila! the Fog Factor is x ??

[si_the_geek]

If you could get a full definition I'm sure it would be possible

[MartinLiss]

From http://inspired2write.com/articles/cutfog.html

How to use the Fog-Index


1) Choose several samples of approximately 100 words each. The samples will usually be taken from one manuscript.
Complete steps 2, 3, and 4 for each sample separately.


2) Calculate the average number of words in each sentence. To do this, count the number of sentences and divide the total number of words in the sample by the number of sentences in the sample. 100 words:5 sentences=20 words in each sentence on average.

3) Count the number of words that have three or more syllables but:
Ignore nouns with capital letters (city names, country names, people's names, etc.) Ignore combination words like 'bottleneck' or 'tabletop'. These are terms that could be expressed differently: the bottle's neck, the neck of the bottle, on top of the table. If a term looks like a combination, test to see if you can express it differently. 'Neighbourhood' may look like a combination but it isn't for our purpose. There isn't another way to say neighbourhood using the same word components. We can't describe neighbourhood as 'hood of the neighbour'. Another example of a word we'd include is 'freewriting' because it's a term in its own right. Ignore words that end with '-ed' or '-es' if the ending is the third syllable, for example 'edited' (ed-it would have only two syllables) and excuses (ex-cuse would have only two syllables). Most words with these endings will be past tense verb forms and plurals. If, however, you have a word like 'catapulted', it will still count because it's still a multi-syllable word (cat-a-pult), even without the '-ed' ending. This process is much easier than it sounds. Try it and see!


4) Add the average number of words per sentence and the number of words with 3 or more syllables and multiply your result by 0.4. All it takes is a second if you're using your calculator.

5) Repeat the process with further samples from the manuscript. The results of each sample can be added together and averaged. To do this, add the readability quotients of all evaluated samples and divide by the number of samples used. You'll find an example below.
In most cases, you'll have a result somewhere between 8-20. Here's what your result means.

Under 10 - Your writing is very easy to read. This is the level you should aim for when writing for most online publications.
10 - The average 15-year-old should be able to understand this level of writing.
11-13 - This writing can be understood by the top 20% of 16-year-olds.
14-16 - A first year college student should be able to understand this level of readability.
17-20(+) - This writing requires a university graduate standard of comprehension.

[siyan]

MSWord has the Flesche Kincaid Grade Level calculation....i think its somewhat similar

-C

[enex]

Hi im a complete novice of vb.net and require my application to calculate the fog index of a peice of writing within a textbox I would be grateful for some sample code or where I should begin The formula is as follows,

Select a sample of at least 100 words. Count the number of sentences. Divide the total number of words in the sample by the number of sentences to get the average sentence length (ASL).
Count the number of words with three or more syllables in the sample. Don't count: 1) proper nouns; 2) hyphenated words; or 3) two-syllable verbs made into three with -es and -ed endings.
Divide this number by the number or words in your sample. For example, 15 long words divided by 100 words gives you 15 percent hard words (PHW).
To get the fog index, add the average sentence length and the percent hard words and multiply this by .4. The formula looks like this: (ASL + PHW) .4 = Grade Level. This is the number of years of schooling the reader would have to have to understand the writing sample.

many thanks in advance

[mendhak]

Enex, I'm locking this thread, please don't bump old threads up. You'll need to create a new thread for your question in the right forum, you could link to this thread if you like as a reference.