# What's first before we can determine the standard deviation?

How do we calculate the mean of a set of data?

What do we have to do first before we can determine the standard deviation of a set of data? (What other values do we need first?)

What is the shape of a normal frequency distribution's graph?

What is the common term for the standardized score of a normal curve?

Define correlation in your own words.

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Research and statistical analysis

How do we calculate the mean of a set of data?

You add up all the data points and divide by the number of data points.

What do we have to do first before we can determine the standard deviation of a set of data? (What other values do we need first?)

You need the mean! You also need how far each data point is from the mean. See this visually in the "study of birds in the ...

#### Solution Summary

This discussion (299 words) is in everyday language suitable for novice. The response includes a powerpoint presentation about the normal curve and z scores, a data set in Excel that computes the statistics in a live model permitting the student to play with the data and change the statistics.