Our students were asked to rate their admiration of Hillary Rodham Clinton on a scale of 1 to 7. They were asked to rate their Jennifer Lopez and Venus Williams on a scale of 1 to 7. The mean rating of Clinton was 4.06 with a standard deviation of 1.70. The mean rating of Jennifer Lopez was 3.72 with a standard deviation of 1.90 and the mean rating of Venus Williams was 2.58 with a standard deviation of 1.46. One of our students rated her admiration of Clinton and Williams at five and her admiration of Lopez at 4.
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Responses
stats(help) - Sue , Thursday, March 12, 2009 at 5:49pm
1)
What is her z score of her admiration rating of Clinton?
I know I am suppose to use the population formula( right?)
5-4.06/1.70=0.55
Please explain to me what I am doing incorrectly.
To calculate the z score for the admiration rating of Clinton, you need to use the formula:
z = (x - μ) / σ
Where:
- x is the observed value (in this case, the student's rating of 5)
- μ is the mean of the ratings for Clinton (4.06)
- σ is the standard deviation of the ratings for Clinton (1.70)
Plugging in the values into the formula:
z = (5 - 4.06) / 1.70
z = 0.55
Therefore, the correct z score for the student's rating of Clinton is 0.55.
It seems like you calculated the z score correctly. Your mistake might be in misinterpreting the z score. The z score represents the number of standard deviations away from the mean that a data point is. In this case, the student's rating of 5 for Clinton is 0.55 standard deviations above the mean.