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studentTTestOneSample

Introduced in: v25.10.0 Applies the one-sample Student’s t-test to determine whether the mean of a sample differs from a known population mean. Normality is assumed. The null hypothesis is that the sample mean equals the population mean. The optional confidence_level enables confidence interval calculation. Notes:
  • At least 2 observations are required; otherwise the result is (nan, nan) (and intervals if requested are nan).
  • Constant or near-constant input will also return nan due to zero (or effectively zero) standard error.
See Also Syntax
studentTTestOneSample([confidence_level])(sample_data, population_mean)
Parameters
  • confidence_level — Optional. Confidence level for confidence intervals. Float in (0, 1). Float*
Arguments Returned value Returns a tuple with two or four elements (if confidence_level is specified): calculated t-statistic, calculated p-value (two-tailed), [calculated confidence-interval-low], [calculated confidence-interval-high]. Confidence intervals are for the sample mean at the given confidence level. Tuple(Float64, Float64) or Tuple(Float64, Float64, Float64, Float64) Examples Without confidence interval
Query
SELECT studentTTestOneSample()(value, 20.0) FROM t;
Response
With confidence interval (95%)
Query
SELECT studentTTestOneSample(0.95)(value, 20.0) FROM t;
Response
See Also
Last modified on June 8, 2026