# Error Correction

Error Correction is an solve path element and occasional extraction method used in hunt puzzles, wherein incorrect information is presented, with the expectation that it will be corrected as part of the solution.

## Puzzle Application

The use of error correction in puzzles can come in two primary forms, depending on what stage of the solve path it is being used for. While it is most commonly used as an aspect of a puzzle as a whole, with extraction after the primary task of correcting erroneous information, it can also be used at the extraction level.

### As a Solve Path Element

In most cases, incorrect or intentionally misleading information will be the focus of a puzzle as a whole, often combined with established puzzle types such as a logic puzzle with an incorrect given, a crossword with incorrect black square placement, or a series of facts or trivia questions that have a particular word wrong.

Depending on the purpose of the error correction (either as the primary challenge of the puzzle, or as a framing mechanism for a different challenge), the correction process may take place at the beginning of a puzzle, prior to another part being able to be solved, or in the middle of a puzzle after another aspect has made it clear that errors need to be corrected. The correction of these errors can have one of several results, each of which having a different "next step" to pursue:

• A solvable puzzle, if the puzzle was not solvable or solvable-but-differently prior
• Comparing the original and fixed versions of the puzzle, and/or their solutions
• A set of corrected elements (numbers, words, letters, etc.)
• Extraction using that set of information
• A set of information that is not a distinct list of elements or a solvable puzzle
• Application of fixed information to help solve another puzzle/order other information

While these applications of this element are not extensive, they should cover the most common uses of error correction as a solve path element.

### As an Extraction Element

When used for extraction, there is one primary use for error correction in puzzles. Sometimes, puzzles will extract a word or phrase that is misspelled, often by a single letter, and expect solvers to extract either the incorrect or correct letters from the errors.

## Strategy

### Solve Path

Depending on the specific use, erroneous information can either be easy to spot (such as in How to Best Write an Essay from Galactic Puzzle Hunt 2017, where it's part of the theming), or intentionally made to only become apparently partway through solving a puzzle. Particularly in cases where an established puzzle type has been altered slightly to be unsolvable, the best way to identify whether error correction is needed is to attempt to solve the puzzle regardless. While there may be false positives in cases where a puzzle has a twist on its usual format, most of the time the presence of "errors" will become quite apparent.

Once the erroneous information has been identified, most error correction puzzles will go smoothly. While some puzzles may involve a non-trivial amount of research to figure out how to correct some errors, there's little to no strategy involved beyond being careful to check one's work and possibly involving a teammate who is knowledgeable in the topic involved.

### Extraction

Conversely, when used as an extraction method, error correction is usually very obvious; as it is primarily implemented via letter swaps in common words or phrases, it will usually be clear to solvers that an error is present (although in some cases, this may be construed as user error until a confirmation is made). What can be more difficult is determining which letters to extract. Some puzzles will use the original (correct) letter from the word or phrase, and some will use the replacement (incorrect) letter. In these cases, the best strategy is to list all letters from both groups, to see if either set spells something significant. In some cases, both will. Either way, this will ensure that the correct extraction is made.

## Notable Examples

### As a Solve Path Element

• How to Best Write an Essay (GPH 2017) (web) - Meta-usage; While the corrections have already been made, part of the puzzle is understanding why they have been made
• Espresso Stand (MITMH 2020) (web) - Presents several mislabelled drinks from Starbucks, Click to revealwith the corrections forming a chain that orders the extracted letters from the other half of the puzzle.
• Orangutan (MITMH 2020) (web) - Click to revealThe fun facts contained in faux IMDb page have incorrect numbers; correcting them and looking at the difference between the two numbers allows for extraction.
• Pig (MITMH 2020) (web) - Click to revealCorrecting spelling errors in the word search entries doesn't result in anything notable, until solvers draw the correct Pig-Pen letter in the space marked by the incorrect letter in the provided grids.

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