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