I am working with the Scenic Model, and the “vshed_qual_SQ” shows four values: 0, 2, 3, and 4. I would like to confirm if the Zero value corresponds to the “Unaffected” category since, according to Griffin et al. 2015 the visual impact index ranges between 1 and 5 (low and high, respectively).

As the first author on the cited paper, in the context of that paper vshed_value.tif is the cumulative impact raster derived from equation 1 (using the linear setting in valuation in the invest model and the appropriate parameter values) and is shown in Fig. 4. vshed_qual_SQ.tif would be derived as quantiles from vshed_value.tif, as described in the user’s guide. These quantiles would not be expected to be reflective of the impact bins described by equation 1, as this maps to a 5 point scale reflected in Bishop and Miller (2007), Figure 5, that has specific preferences tied to each value - whereas quantiles are just relative measures of a distribution.

@jdouglass will be in a better position to answer your specific question about those values {0, 2, 3, and 4} and how they relate to the quantiles - that does seem a bit off to me, though maybe you only have a few discrete bins of values.

As of InVEST 3.13.0, the model’s vshed_qual.tif output has pixel values from 0-4 rather than 1-5. So yes, in this case, 0 would be “no impact” and 4 would be “high impact”.

I have corrected the User’s Guide chapter to note the correct pixel values.