How to get levels for Fry Graph readability formula?

Question

Hi,

I'm working in an application (C#) that applies some readability formulas to a text, like Gunning-Fog, Precise SMOG, Flesh-Kincaid.

Now, I need to implement the Fry-based Grade formula in my program, I understand the formula's logic, pretty much you take 3 100-words samples and calculate the average on sentences per 100-words and syllables per 100-words, and then, you use a graph to plot the values.

Here is a more detailed explanation on how this formula works.

I already have the averages, but I have no idea on how can I tell my program to "go check the graph and plot the values and give me a level." I don't have to show the graph to the user, I only have to show him the level.

I was thinking that maybe I can have all the values in memory, divided into levels, for example:

Level 1: values whose sentence average are between 10.0 and 25+, and whose syllables average are between 108 and 132.

Level 2: values whose sentence average are between 7.7 and 10.0, and .... so on

But the problem is that so far, the only place in which I have found the values that define a level, are in the graph itself, and they aren't too much accurate, so if I apply the approach commented above, trying to take the values from the graph, my level estimations would be too much imprecise, thus, the Fry-based Grade will not be accurate.

So, maybe any of you knows about some place where I can find exact values for the different levels of the Fry-based Grade, or maybe any of you can help me think in a way to workaround this.

Thanks

Answer 1

Well, I'm not sure about this being the most efficient solution, neither the best one, but at least it does the job.

I gave up to the idea of having like a math formula to get the levels, maybe there is such a formula, but I couldn't find it.

So I took the Fry's graph, with all the levels, and I painted each level of a different color, them I loaded the image on my program using:

Bitmap image = new Bitmap(@"C:\FryGraph.png");

image.GetPixel(int x, int y);

As you can see, after loading the image I use the GetPixel method to get the color at the specified coordinates. I had to do some conversion, to get the equivalent pixels for a given value on the graph, since the scale of the graph is not the equivalent to the pixels of the image.

In the end, I compare the color returned by GetPixel to see which was the Fry readability level of the text.

I hope this may be of any help for someone who faces the same problem.

Cheers.

Answer 2

You simply need to determine the formula for the graph. That is, a formula that accepts the number of sentences and number of syllables, and returns the level.

If you can't find the formula, you can determine it yourself. Estimate the linear equation for each of the lines on the graph. Also estimate the 'out-of-bounds' areas in the 'long words' and 'long sentences' areas.

Now for each point, just determine the region in which it resides; which lines it is above and which lines it is below. This is fairly simple algebra, unfortunately this is the best link I can find to describe how to do that.