CHI square independent test (small expected frequency)

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SUMMARY

The discussion focuses on addressing the issue of small expected frequencies in a Chi-square test for independence, specifically when analyzing age groups (21-30, 31-36, and 37+). The user is attempting to combine these age categories to ensure that the expected frequency meets the minimum requirement of 5. It is concluded that combining the age groups 21-30 and 31-36, or 31-36 and 37+, can resolve the issue of low expected frequencies. The importance of calculating both combinations to verify consistency in results is emphasized.

PREREQUISITES
  • Understanding of Chi-square tests for independence
  • Familiarity with expected frequency calculations
  • Knowledge of age group categorization in statistical analysis
  • Basic statistical hypothesis testing concepts
NEXT STEPS
  • Learn about Chi-square test assumptions and conditions
  • Study how to calculate expected frequencies in contingency tables
  • Explore methods for combining categories in categorical data analysis
  • Investigate the implications of small sample sizes on statistical tests
USEFUL FOR

Statisticians, data analysts, and students studying statistics who are working with Chi-square tests and need to manage small expected frequencies effectively.

somecelxis
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Homework Statement


the expected frequency for the age of (21-30, 31-36, more than or equal to 37) for operation is less than 5 , so combination of these numbers are required for the expected frequency to be more than or equal to 5 .
my question is which numbers should i combine?

would my ans be different?

Homework Equations

The Attempt at a Solution


in the solution, i combine the (21-30, 31-36, more than or equal to 37) for normal birth to get my Observed frequency = 34 and expected frequency = 38.37...

for operation, combine the (21-30, 31-36, more than or equal to 37) for normal birth to get my Observed frequency = 12 and expected frequency = 7.57...

can i combine less than( 21 and 21-30 ) , (31-36 , more than 37) ?[/B]
 

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This may be a solution to your problem.

I'm not sure if this was your plan. I would think if you combine the the rows 21-30 and 31-36, or 31-36 and 37+, then that'd fix the problem.

For your second question, why don't you just compute both and see if one contradicts the decision of the other?
 

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