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7: Chi Square Analysis

  • Page ID
    171259
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    • 7.1: Binomial Distribution
      The binomial distribution predicts the probability of a given number of successes in independent trials with two possible outcomes. Worked examples show how to identify the number of trials and outcome probability, then calculate probabilities for exact counts or ranges of counts.
    • 7.2: Phenotypic Ratios May Not Be As Expected
      Observed offspring ratios can differ from genetic predictions because of random sampling or differences in survival. Chi-square testing helps assess whether deviations are consistent with chance variation or suggest that the genetic assumptions need reconsideration.
    • 7.3: Goodness-of-Fit Test
      Chi-square goodness-of-fit tests compare observed counts with counts expected under a null hypothesis. Worked examples show how to calculate the test statistic, determine degrees of freedom, and decide whether to reject the predicted distribution.


    7: Chi Square Analysis is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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