Which would you place in parentheses: the expansion or the abbreviation? [closed]

The Modern Language Association (MLA) style, which is commonly used, always puts acronyms and initialisms in parentheses after the first time they are used (not the other way around). For example: The Modern Language Association (MLA) publishes its own style guide.

The MLA Handbook for Writers of Research Papers devotes an entire chapter to abbreviations.

The Associated Press Stylebook is a little less helpful in handling abbreviations. It says that the first time an item is used, it should be spelled out fully. Then, if the abbreviation or acronym is common enough to be well known publicly, it can be used on subsequent reference. AP style does not use a parenthetical explanation behind the first mention. It just uses the acronym or abbreviation after the first full mention. For example: The National Organization of Women met at the courthouse. NOW was organized in ....

The AP Style Guide also notes that certain abbreviations or acronyms are common enough to be used on first reference, that is without having been spelled out first. (As examples, CIA and FBI can be used on first reference; Central Intelligence Agency and Federal Bureau of Investigation do not need to be spelled out on first mention.) You basically have to consult the entries in the AP Stylebook for whether an abbreviation is common enough to not be spelled out.

The Economist does it like this: “European Central Bank (ECB)”, “‘quantitative easing’ (QE)”. My impression is that this is more common than the reverse pattern. It parallels the legal usage whereby a general description is given and then a shorthand—e.g., “(‘The Company’)”, “(‘The Client’)”—is introduced in parentheses and quotes.