Compare independent sample means without assuming equal variances.
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Welch two sample t statistic
Row alignment does not indicate pairing. Calculate the Welch statistic as (mean A − mean B) ÷ √(sA²/nA + sB²/nB), using sample variances with denominator n − 1. Real inference also needs independent observations, defensible sampling and suitable distributions; these small tables cannot verify those conditions.
Observation label
Group A infiltration (mm/hour)
Group B infiltration (mm/hour)
1
18
15
2
20
17
3
22
20
4
24
22
5
26
26
Two fictional independent samples All values are synthetic.
Resource description
Two fictional independent samples
Use the resource carefully
State the unit and the part of the resource you used. A pattern in a fictional dataset is evidence for that exercise; it does not establish a fact about a real place.
Check whether an explanation is supported by the data or needs additional geographical knowledge. For statistical tasks, a calculated result does not establish causation or significance by itself.