In this video you will learn how to use StatCrunch calculators for continuous distributions. These calculators allow for the calculation of a probability given a reference value, or the calculation of a reference value associated with a specific probability. In this video I will focus on using the normal calculator but the same techniques can be applied to use the calculators for other continuous distributions. To find the StatCrunch calculators under the stat menu choose calculators. Here's the list of the continuous distribution calculators built into StatCrunch. For this example I'm going to choose normal. This loads a calculator for a normal distribution with a mean of zero and a standard deviation of one or also known as the standard normal distribution. The parameters defining the distribution can be changed by editing the inputs and the first row below the graph. For the normal calculator these inputs are labeled as mean and standard deviation. The second row of inputs is used to find probabilities associated with the distribution. By default the normal calculator shows the area below the mean of zero in red and indicates the probability of a standard normal variable being at or below zero to be 0.5. Now let's compute a probability associated with another reference value I'm going to type negative 2.1 for the reference value which is the box to the right of the less than or equal to sign. I'll now click compute and as you can see the probability of being less than or equal to negative 2 . 1 is computed to be approximately 0.018. Another way of thinking about this result is that approximately 1.8 percent of the area under this distribution is below - 2.1. To find the probability above this reference value you can click on the inequality sign to change it from less than or equal to; to greater than or equal to for now I'll leave it at less than or equal to. StatCrunch calculators can also be used in reverse to find a reference value given a probability to be above or below it. This is often done when finding the critical value for a hypothesis test or a multiplier in a confidence interval. In this case for the standard normal distribution to find the value where there is a probability of 0.05 of being above it, I'm going to switch the inequality sign to greater than or equal to. I'm now going to enter 0.05 for the probability input which is to the right of the equal sign. This input accepts values between 0 & 1. I'll now click compute. The distributional picture shown is updated with five percent of the area colored in red. The reference value is also computed to be approximately 1.64. To find the probability of falling between two reference values, I'm now going to click the between button at the top of the screen. By default this produces a new graph with the area between the default reference values of -1 and 1 colored in red. The probability of falling between these two reference points is also shown to be approximately 0.68. Now, I'm going to change the first reference value to be negative 0.5 and the second to be 2. The first reference value must always be less than the second one. I'll now click compute. The area between negative 0.5 and 2 is shown in red and corresponds to a probability of approximately 0.67. One of the two reference values, or the associated probability, must be left empty when using the calculator so we'll fill in the remaining input. To switch back to the original calculator with only one reference value you can click the standard button at the top of the window.