Statistics Review Questions for the Test
For a normal distribution, the z value for an x value that is to the left of the mean is always:
negative
For the standard normal distribution, the z value gives the distance between the mean and a point in terms of the:
standard deviation
The z value for a normal distribution curve is always:
zero
A continuous random variable is a random variable that can:
assume any value in one or more intervals
The normal probability distribution is applied to:
continuous random variable
The total area under a normal distribution curve to the left of the mean is always:
equal to .5
For a normal distribution, the z value for the mean is always:
equal to zero
The probability that a continuous random variable x assumes a single value is always:
equal to zero
For a continuous random variable x, the area under the probability distribution curve between any two points is always:
in the range of 0 to 1
Which of the following is not a characteristic of the normal distribution? (answer in parenthesis)
-The total area under the curve is 1 -The curve is symmetric about the mean -(The value of the mean is always greater than the value of the standard deviation) -The two tails of the curve extend indefinitely
For the standard normal distribution the mean is always:
0 and the standard deviation 1
The parameters of a normal distribution are always:
u and o (mean and standard deviation)
For a normal distribution, the z value that is to the right of the mean is always:
positive
For a normal distribution, the spread of the curve decreases and its height increases as:
the standard deviation decreases