On 2017 Mar 04, Lydia Maniatis commented:

What Ratnasingam and Anderson are doing here is analogous to this imaginary example: Let’s say that I have a strong allergy to food x, a milder one to food y, none to food z, and so on, and that my allergies produce various symptoms. Let’s assume also that some of these effects can be interpreted fairly straightforwardly in terms of formal structural relationships between my immune system and the molecular components of the foods, and others not. For these others, we can assume either a functional rationale or perhaps consider them a side effect of structure or function. We don’t know yet. For other individuals, other allergy/food combinations have corresponding effects. Again, if we know something about the individual we can predict some of the allergic reactions based on known principles.

How much sense would it make now, to conduct a study whose goal is: “to articulate general principles that can predict when the size of an allergic reaction will be large or small for arbitrarily chosen food/patient combinations…. What (single) target food generates the greatest allergic difference when ingested by two arbitrarily chosen patients?” (“Our goal is to articulate general principles that can predict when the size of induction will be large or small for arbitrarily chosen pairs of center-surround displays…. What (single) target color generates the greatest perceptual difference when placed on two arbitrarily chosen surround colors?”)

Furthermore, having gotten their results, our researchers now decline to attempt to interpret them in terms of the nuanced understanding already available.

The most striking thing about the present study is that a researcher who has done (unusually) good work in studying the role of structure and chromatic/lightness relationships in the perception of color is now throwing all this insight overboard, ignoring what is known about these factors and lumping them all together, in the hope of arriving at some magic, universal formula for “simultaneous contrast” that is blind to them. Obviously the effort is bound to fail, and the title – framed as a question, not an answer – is evidence of this. Here is a sample, revealing caveat:

“Finally, it should also be noted that although some of our comparisons involved target–surround combinations in which some targets can appear as both an increment and decrement relative to the two surrounds, which would induce differences in both hue and saturation (e.g., red and green). Such pairs may be rated as more dissimilar than two targets of the same hue (e.g., red and redder), but it could be argued that this does not imply that the size of simultaneous contrast is larger in these conditions. However, it should be noted that such conditions are only a small subset of those tested herein.” Don’t bother us with specifics, we’re lumping.

As the authors discuss in their introduction, studies (treating “simultaneous contrast” in a crude, structure-and-relationship-blind way) produce conflicting results: “The conflicting empirical findings make it difficult to articulate a general model that predicts when simultaneous contrast effects will be large or small, since there is currently no model that captures how the magnitude of induction varies independently of method used…. “ Of course. When you don’t take into account relevant principles, and control for relevant factors, your results will always mystify you.

The conflation between, or refusal to distinguish explicitly, cases in which transparency arises and in which it does not arise is really inexplicable.

"The suggestion that the strongest forms of simultaneous contrast arise in conditions that induce the perception of transparency gains conceptual support from evidence showing that transparency can generate dramatic transformations in both perceived lightness and color..." But the contextual conditions that produce transparency are really quite...transparent...There's no clear reason to lump these with situations that are perceptually and logically distinct.

Also: "In simultaneous contrast displays, the targets and surrounds are also texturally continuous, in the sense that they are both uniform, but there are no strong geometric cues for the continuation of the surround through the target region of the kind known to give rise to vivid percepts of transparency (such as contours or textures). It is therefore difficult to generate a prediction for when transparency should be induced in homogeneous center-surround patterns, or how the induction of transparency should modulate the chromatic appearance of a target as a function of the chromatic difference between a target and its surround."

First, I'll pay him the compliment of saying that I don't think that it would be that difficult for Anderson to generate predictions for when transparency should occur...(I think even I could do it). Second, if this theoretical gap really exists, then this is the problem that should be addressed, not "what happens if we test a lot of random combinations and average the results." It might be useful to take into consideration a demo devised by Soranzo, Galmonte & Agostini (2010) which is a case of transparency effect that lacks the "cues" mentioned here - and thus by these authors' criteria qualifies as a basic simultaneous contrast display. (I don't think its that difficult to explain, but maybe I haven't thought about it enough.)

On 2017 Mar 04, Lydia Maniatis commented:

What Ratnasingam and Anderson are doing here is analogous to this imaginary example: Let’s say that I have a strong allergy to food x, a milder one to food y, none to food z, and so on, and that my allergies produce various symptoms. Let’s assume also that some of these effects can be interpreted fairly straightforwardly in terms of formal structural relationships between my immune system and the molecular components of the foods, and others not. For these others, we can assume either a functional rationale or perhaps consider them a side effect of structure or function. We don’t know yet. For other individuals, other allergy/food combinations have corresponding effects. Again, if we know something about the individual we can predict some of the allergic reactions based on known principles.

How much sense would it make now, to conduct a study whose goal is: “to articulate general principles that can predict when the size of an allergic reaction will be large or small for arbitrarily chosen food/patient combinations…. What (single) target food generates the greatest allergic difference when ingested by two arbitrarily chosen patients?” (“Our goal is to articulate general principles that can predict when the size of induction will be large or small for arbitrarily chosen pairs of center-surround displays…. What (single) target color generates the greatest perceptual difference when placed on two arbitrarily chosen surround colors?”)

Furthermore, having gotten their results, our researchers now decline to attempt to interpret them in terms of the nuanced understanding already available.

The most striking thing about the present study is that a researcher who has done (unusually) good work in studying the role of structure and chromatic/lightness relationships in the perception of color is now throwing all this insight overboard, ignoring what is known about these factors and lumping them all together, in the hope of arriving at some magic, universal formula for “simultaneous contrast” that is blind to them. Obviously the effort is bound to fail, and the title – framed as a question, not an answer – is evidence of this. Here is a sample, revealing caveat:

“Finally, it should also be noted that although some of our comparisons involved target–surround combinations in which some targets can appear as both an increment and decrement relative to the two surrounds, which would induce differences in both hue and saturation (e.g., red and green). Such pairs may be rated as more dissimilar than two targets of the same hue (e.g., red and redder), but it could be argued that this does not imply that the size of simultaneous contrast is larger in these conditions. However, it should be noted that such conditions are only a small subset of those tested herein.” Don’t bother us with specifics, we’re lumping.

As the authors discuss in their introduction, studies (treating “simultaneous contrast” in a crude, structure-and-relationship-blind way) produce conflicting results: “The conflicting empirical findings make it difficult to articulate a general model that predicts when simultaneous contrast effects will be large or small, since there is currently no model that captures how the magnitude of induction varies independently of method used…. “ Of course. When you don’t take into account relevant principles, and control for relevant factors, your results will always mystify you.

The conflation between, or refusal to distinguish explicitly, cases in which transparency arises and in which it does not arise is really inexplicable.

"The suggestion that the strongest forms of simultaneous contrast arise in conditions that induce the perception of transparency gains conceptual support from evidence showing that transparency can generate dramatic transformations in both perceived lightness and color..." But the contextual conditions that produce transparency are really quite...transparent...There's no clear reason to lump these with situations that are perceptually and logically distinct.

Also: "In simultaneous contrast displays, the targets and surrounds are also texturally continuous, in the sense that they are both uniform, but there are no strong geometric cues for the continuation of the surround through the target region of the kind known to give rise to vivid percepts of transparency (such as contours or textures). It is therefore difficult to generate a prediction for when transparency should be induced in homogeneous center-surround patterns, or how the induction of transparency should modulate the chromatic appearance of a target as a function of the chromatic difference between a target and its surround."

First, I'll pay him the compliment of saying that I don't think that it would be that difficult for Anderson to generate predictions for when transparency should occur...(I think even I could do it). Second, if this theoretical gap really exists, then this is the problem that should be addressed, not "what happens if we test a lot of random combinations and average the results." It might be useful to take into consideration a demo devised by Soranzo, Galmonte & Agostini (2010) which is a case of transparency effect that lacks the "cues" mentioned here - and thus by these authors' criteria qualifies as a basic simultaneous contrast display. (I don't think its that difficult to explain, but maybe I haven't thought about it enough.)