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A clinical psychologist administers a short anxiety inventory to four patients. The recorded scores are 12, 18, 9, and 15. Briefly explain how the psychologist should calculate the median for this specific set of scores and provide the final median value.
Question: A clinical psychologist administers a short anxiety inventory to four patients. The recorded scores are 12, 18, 9, and 15. Briefly explain how the psychologist should calculate the median for this specific set of scores and provide the final median value.
Sample answer: First, the psychologist must arrange the scores from lowest to highest: 9, 12, 15, and 18. Since there is an even number of scores, the median is calculated by finding the value exactly halfway between the two middlemost scores (12 and 15), resulting in a median of 13.5.
Key points:
- Arranges the scores sequentially from lowest to highest (9, 12, 15, 18).
- Identifies the two middlemost scores as 12 and 15.
- Calculates the halfway point between the two middle scores.
- Determines the final median value is 13.5.
Rubric: Responses must correctly order the scores, identify the two middle values (12 and 15), describe finding the midpoint between them because there is an even number of scores, and calculate the correct median of 13.5.
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Research Methods in Psychology - 4th American Edition @ KPU
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A clinical psychologist administers a short anxiety inventory to four patients. The recorded scores are 12, 18, 9, and 15. Briefly explain how the psychologist should calculate the median for this specific set of scores and provide the final median value.