This preview shows page 1. Sign up to view the full content.
Unformatted text preview: The chi-square statistic is a measure of how far the observed counts in a two-way table are from the expected counts. The formula for the statistic is The chi-square statistic is a sum of terms, one for each cell in the table. Cell counts required for the Chi-squared test: You can safely use the chi-square test with critical values from the chi-square distribution when no more than 20% of the expected counts are less than 5 and all individual expected counts are 1 or greater. In particular, all four expected counts in a 2 2 table should be 5 or greater. The expected counts are the counts we expect if all the proportions are equal. A large chi-square test statistic supports the alternative hypothesis. Check conditions: 1. SRS or random allocation 2. All expected counts>=5...
View Full Document
This note was uploaded on 02/27/2012 for the course STAT 121 taught by Professor Patticolling during the Winter '11 term at BYU.
- Winter '11