Observed values

Definition

Observed values are the actual data points collected from an experiment or survey. These values are used to compare against expected values in statistical tests.

5 Must Know Facts For Your Next Test

1. Observed values are crucial for calculating the chi-square statistic.
2. They represent empirical data, as opposed to theoretical expectations.
3. In a goodness-of-fit test, observed values are compared to expected frequencies to determine if there is a significant difference.
4. A large difference between observed and expected values can indicate that the model does not fit the data well.
5. The sum of the differences between observed and expected values squared, divided by the expected value, forms part of the chi-square formula.

Review Questions

• What role do observed values play in calculating the chi-square statistic?
• How are observed values different from expected values?
• Why is it important to compare observed and expected values in a goodness-of-fit test?

Related terms

Expected Values: Theoretical frequencies that one would expect to obtain if a specific hypothesis were true.

Chi-Square Statistic: A measure used in statistics to assess how much observed counts deviate from expected counts under a specified hypothesis.

Goodness-of-Fit Test: A statistical test used to determine if a set of observed frequencies matches expected frequencies.