Hope student researchers want to determine if students yawning (when being yawned at) is asso-ciated with the time of day (morning, afternoon, and evening). They found the following results when they yawned in front of people around campus:

• Morning: 25 of the 39 people yawned
• Afternoon: 15 of the 38 people yawned
• Evening: 29 of the 44 people yawned
-Are validity conditions met to conduct a chi-square test of association?
A) Yes, since 39, 38, and 44 are all larger than 20.
B) Yes, since 121 is larger than 20.
C) Yes, since each cell in the table has at least 10 observations.
D) No, since several cells in the table have less than 20 observations.

Question

Hope student researchers want to determine if students yawning (when being yawned at) is asso-ciated with the time of day (morning, afternoon, and evening). They found the following results when they yawned in front of people around campus:
 
• Morning: 25 of the 39 people yawned
• Afternoon: 15 of the 38 people yawned
• Evening: 29 of the 44 people yawned
-Are validity conditions met to conduct a chi-square test of association?
A) Yes, since 39, 38, and 44 are all larger than 20.
B) Yes, since 121 is larger than 20.
C) Yes, since each cell in the table has at least 10 observations.
D) No, since several cells in the table have less than 20 observations.

Quizplus · Accepted Answer

The validity condition for a chi-square test of association is that each expected frequency in the contingency table should be at least 5. Here, each cell has at least 10 observations, meeting the condition.

Hope Student Researchers Want to Determine If Students Yawning (When