The common symptoms of an overactive thyroid are weight loss, increased appetite, irritability, rapid heart rate and anxiety, according to the Office on Women's Health, whereas underactive thyroid symptoms include weight gain, cold sensitivity, fatigue, depression and muscle weakness.
Z-Scores Explained. A z-score is a score that falls somewhere within the standard normal distribution. Its counterpart on the standard distribution is the standard score. The standard normal distribution and z-score allow all the standardized scores to be weighed equally through a few calculations. z-score is a score that falls somewhere within the standard normal distribution. Its counterpart on the standard distribution is the standard score. The standard normal distribution and z-score allow all the standardized scores to be weighed equally through a few calculations.
The normal random variable of a standard normal distribution is called a standard score or a z-score. Every normal random variable X can be transformed into a z score via the following equation: z = (X - Î¼) / Ï. where X is a normal random variable, Î¼ is the mean of X, and Ï is the standard deviation of X.he standard normal distribution is a special case of the normal distribution. It is the distribution that occurs when a normal random variable has a mean of zero and a standard deviation of one.