Standard Deviation Link for follow along worksheet: GNjNDE1ZTA GNjNDE1ZTA
Launch Compare Groups You are given the following data from three groups: 1. Find and state the measures of central tendency (mean, median, mode, & range) for each group. 2. Do an individual box & whiskers plot of the data for each of the groups. Group Group Group
3. On the basis of the dot plots, what can you say about the three groups? Explain.
Standard Deviation… The Standard Deviation is a number that measures how far away each number in a set of data is from their mean or a measure of how spread out numbers are. If the Standard Deviation is LARGE, it means the numbers are spread out from their mean. If the Standard Deviation is SMALL, it means the numbers are close to their mean.
The first step to finding the Standard Deviation is to find all the distances from the mean. Fill in the chart. +/- Distance Mean = ______________ from mean
Next, square all the distances to turn them into positive numbers then collect the squared sum. Fill in the chart. What does the squared sum tell you about the data ____________________________________________________ Variance- average of the sum of the square differences
Squared Sum = ______. Step 3: Divide by (n - 1) for the population variance where n represents the amount of numbers you have. Finally, take the Square Root of the average distance. Standard Deviation = _________.
There is a Standard Deviation Equation, but it can also be commuted using a calculator 2
Explore New Light Bulbs or Not? The data below are the lifetimes (in hours) for 10 light bulbs from a new brand that your school is considering for use in the football stadium light fixtures: 2009, 2015, 2002, 1979, 2032, 1991, 2016, 2030, 2001, * Devise a plan to help the school make a decision about whether to change to the new bulbs. Explain your plan, including any information you might need. Compute any statistics on the new brand you think would help with the argument.
* The standard deviation for the lifetimes of bulbs from the brand currently in use is 40 hours. What does the standard deviation that you computed for the sample of light bulbs from the new brand tell you about how this brand might compare with the old brand?