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Usage and Grammar
Q. “The larger the parameter, the smaller the region.” This construction is just fine, but what’s the justification for implied rather than fully present verbs? Why don’t we get to imply parts of speech whenever we want to? And as an editor, am I wrong to delete the verbs when they are used? “The larger the parameter is, the smaller is the region”?
A. You are right to delete the verbs. Your first version is idiomatic English; the second is pedantic overkill. As for your whys and wherefores, I’m afraid you will need a linguist rather than a style guide to get the technical backstory. Let us know what you find out!