outlier

7 synonyms and 2 antonyms for outlier, grouped by meaning and by how common each one is.

Noun — A data point that sits far away from the rest of a set of results, and which may signal a real extreme case or a measurement error.

Synonyms

Everyday swaps

Common words most readers know — safe in any writing.

exception

Less common

Still standard English, but they carry more weight.

anomaly deviation maverick

Rare, literary or technical

Precise, but they will stand out — check the sense before using one.

aberration one-off odd one out

Synonyms by Meaning

1. noun

A data point that sits far away from the rest of a set of results, and which may signal a real extreme case or a measurement error.

“One household reported an income of £4 million, an outlier that dragged the mean upwards.”

anomaly aberration exception deviation

Opposites

norm average

2. noun

A person or thing that stands markedly apart from the others in a group.

“Among European capitals, its rents make it a real outlier.”

exception one-off maverick odd one out

How to use outlier

The word patterns that sound natural to a native speaker.

statistical outlier remove outliers a clear outlier outlier detection

Neutral; standard in statistics and increasingly common in general writing.

Etymology

From out and the verb lie, meaning something lying outside the main body; the geological sense is recorded before the statistical one.

Full origin of outlier →

Frequently asked questions

What is the difference between an outlier and an anomaly?

An outlier is defined statistically: it lies far from the rest of the distribution. An anomaly implies something is genuinely wrong or unexplained. Every anomaly may look like an outlier, but many outliers are legitimate extreme values rather than errors.

Should you remove outliers from your data?

Only if you can justify it. Remove a point when you have evidence it is a recording or measurement error. Removing points simply because they are inconvenient biases the result, and in skewed data a median or a robust method is a better answer than deletion.

How are outliers identified?

Common rules are values more than 1.5 times the interquartile range beyond the first or third quartile, or more than about three standard deviations from the mean. Both are conventions, not laws, and the right threshold depends on the data.

People also searched

average exception norm deviation anomaly maverick aberration

Nearby words

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