Which one of the following statements does not apply to normal probability curve?

Correct option is D

Kurtosis refers to the sharpness of the peak of the curve. For a normal distribution, the kurtosis is not zero. It has a kurtosis value of 3, meaning the distribution is mesokurtic (moderately peaked). Thus, kurtosis being zero does not apply to the normal probability curve.

Information Booster
1. Symmetry of the Normal Distribution:
1.1. The normal curve is bilaterally symmetrical, meaning if you were to fold it at the mean, both halves would match perfectly.
1.2. Symmetry indicates that the probability of a score being above or below the mean is the same.
2. Bell-shaped Curve:
2.1. The bell shape reflects the frequency distribution of a dataset, where the majority of values are concentrated around the mean, with fewer extreme values on both ends.
2.2. The bell shape indicates that as values move further away from the mean, they become less likely to occur, which results in the tapering of the curve.
3. Zero Skewness:
3.1. A skewness value of zero indicates that the distribution is perfectly symmetrical, with equal tails on both sides of the mean.
3.2. If skewness is positive or negative, the distribution is said to be skewed to the right or left, respectively.
4. Kurtosis of the Normal Distribution:
4.1. Kurtosis measures the "tailedness" or sharpness of the peak of a distribution. A normal distribution has a kurtosis of 3 (mesokurtic), meaning it has a moderate peak.
4.2. When the kurtosis is greater than 3, it indicates a leptokurtic distribution (more peaked), and when it is less than 3, it indicates a platykurtic distribution (flatter).