Notation: getting one value from arg max

AI Thread Summary
The discussion focuses on how to denote the arg max when multiple indices yield the same maximal value, specifically wanting to return the last index. Participants express uncertainty about existing notation for this scenario. Suggestions include using a modified notation like max(argmax) to clarify the intent. However, no standardized notation is agreed upon, and the need for a clear representation remains. The conversation highlights a gap in mathematical notation for this specific case.
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I want to take the arg max over a number of functions as below, however it is possible that there are multiple i's for which the result is maximal. How do i denote that I want to take the last possible i, for example if it results in 3 and 5 I want it to return 5, is there notation available for this?

arg\,max_{i} f_{i}(\mathbf{x})
 
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I am not aware of such notation, but it's unclear to me whether you're looking to denote $$ argmax f\text{ where }f(x)=max_{\{i\}}f_i(x) $$ or $$ max_{\{i\}} argmax f_i $$
 
I want to get the index of the function with the highest value for that particular x, and if there are several, the last index should be returned.
 
OK, so ## \max(\text{argmax}_{i}f_i(x)) ##... Sorry, can't think of a standard notation for that, maybe others will.
 
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