Performs a Z-test to compare a sample mean to a known population mean or to compare two sample means when population variances are known.
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Enter Sample Mean, Population Mean (for one-sample test), Sample Standard Deviation, Sample Size, Sample Mean 2 (for two-sample test), Sample Standard Deviation 2 (for two-sample test), Sample Size 2 (for two-sample test), Test Type, and Significance Level (alpha) in the units shown.
Read Z-score (Two-Sample), Z-score (One-Sample), P-value (Two-tailed), Z-score, and Reject Null Hypothesis? in the results panel. Results update as you change the inputs.
Choose a preset to load an example, then adjust the values for your situation.
See the inputs and their calculated results.
Sample Mean: 27; Population Mean (for one-sample test): 25; Sample Standard Deviation: 4; Sample Size: 35; Sample Mean 2 (for two-sample test): 22; Sample Standard Deviation 2 (for two-sample test): 4; Sample Size 2 (for two-sample test): 35; Test Type: One-Sample Z-test; Significance Level (alpha): 0.05
Z-score (Two-Sample): 0; Z-score (One-Sample): 2.958039892; P-value (Two-tailed): 1.991324111; Z-score: 2.958039892; Reject Null Hypothesis?: No
Sample Mean: 30; Population Mean (for one-sample test): 25; Sample Standard Deviation: 7; Sample Size: 50; Sample Mean 2 (for two-sample test): 22; Sample Standard Deviation 2 (for two-sample test): 4; Sample Size 2 (for two-sample test): 35; Test Type: One-Sample Z-test; Significance Level (alpha): 0.05
Z-score (Two-Sample): 0; Z-score (One-Sample): 5.050762723; P-value (Two-tailed): 1.987310663; Z-score: 5.050762723; Reject Null Hypothesis?: No
Sample Mean: 28; Population Mean (for one-sample test): 20; Sample Standard Deviation: 5; Sample Size: 40; Sample Mean 2 (for two-sample test): 25; Sample Standard Deviation 2 (for two-sample test): 6; Sample Size 2 (for two-sample test): 45; Test Type: Two-Sample Z-test; Significance Level (alpha): 0.05
Z-score (Two-Sample): 2.51312345; Z-score (One-Sample): 0; P-value (Two-tailed): 1.041216854; Z-score: 2.51312345; Reject Null Hypothesis?: No
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