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9: Introduction to t-tests

  • Page ID
    14502
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    • 9.1: The t-statistic
      The z-statistic was a useful way to link the material and ease us into the new way to looking at data, but it isn’t a very common test because it relies on knowing the populations standard deviation, σ, which is rarely going to be the case. Instead, we will estimate that parameter σ using the sample statistic s in the same way that we estimate μ using X. Our new statistic is called t, and for testing one population mean using a single sample (called a 1-sample t -test)
    • 9.2: Hypothesis Testing with t
      Hypothesis testing with the t-statistic works exactly the same way as z-tests did, following the four-step process of (1) Stating the Hypothesis, (2) Finding the Critical Values, (3) Computing the Test Statistic, and (4) Making the Decision.
    • 9.3: Confidence Intervals
    • 9.E: Introduction to t-tests (Exercises)


    This page titled 9: Introduction to t-tests is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Foster et al. (University of Missouri’s Affordable and Open Access Educational Resources Initiative) via source content that was edited to the style and standards of the LibreTexts platform.