Group Projects: May 31, 2006

In this project we will be studying the amount of alcoholic drinks consumed by college students during Memorial Day weekend. Our sample will be a sample of convenience, the students in this classroom. Each student will write on a piece of paper how many alcoholic drinks (1 drink is considered to be 8oz of some sort of mixed drink, 1 beer, or 1 shot) they drank this weekend (Friday evening through Monday evening). We will then collect the data and analyze it using JMP IN.

Once the data has been collected we must enter it into JMP:

1)  First to open JMP IN on the computer click on START\Programs\Mathematics and Stat\JMP IN 5.1\JMP IN 5.1.

We will then be creating a new data table so under the JMP starter click on NEW DATA TABLE.

2)  To load our data, on the left hand side of the screen under columns, right click on column 1and select COLUMN INFO. Name the column “Number of drinks” all else should remain the same, and then click OK.

3)  You must now begin filling down the column, the class data. Make sure not to make any mistakes when entering the data.

Now that your data has been entered we can first order the data:

1)  On the top toolbar click on TABLES\SORT.

2)  When the JMP IN: Sort box appears on the screen click on “Number of drinks” and then the BY button and then SORT.

3)  This should sort your data from lowest to highest. From here we can compute the five number summary by hand. Do so and write your summary below.

Min. Value:

Lower Quartile:

Median:

Upper Quartile:

Max. Value:

4)  Also by hand (or using a calculator) compute the mean and standard deviation of the data. Show your work below.

Mean:

Standard Deviation:

Now that our data has been sorted and analyzed by hand, we can analyze the data using JMP.

1)  On the top toolbar click on ANALYZE\Distribution

2)  When the new screen comes up we want to click on “Number of drinks” and then the Y,Columns button. This will put the variable “Number of drinks” into the plot that we make. Then click on the OK button.

3)  Once your histogram and box plot show up we can rotate the graph so that it is horizontal by clicking on the red arrow next to “Number of drinks”. Then under Display Options choose Horizontal Layout.

4)  We can also change the intervals by right clicking on the horizontal axis and selecting axis settings. Here you can choose the min value for the x-axis to start at, the increments that the intervals will be, and the max value for the x-axis.

5)  To show the frequencies on the graph click the red arrow next to the “Number of drinks” again and under Histogram Options choose Count Axis (this will give you frequencies) to get relative frequencies choose Density Axis.

6)  Next to the graph we can see the quantiles of the data, the ones that we are interested in would be the max, min, two quartiles, and the median. See if these match the ones that you have computed in the above section.

7)  We can also see next to the graph the Moments, the ones that we are interested in are the mean and standard deviation. Again, see if these match the ones that you have computed above.

8)  Finally, to produce a stem-and-leaf plot again click on the red arrow next to “Number of drinks” and choose stem-and-leaf.

9)  From here play around with the options of the histogram to change the color and size.

To add the histogram to a word document: on the toolbar find (to the right) the selection button (looks like a cross to the right of the question mark) and click on it. Then select the histogram, quantile chart, moments chart, and the stem-and-leaf plot and right click and choose copy. Then, paste all of these items to the end of this word document. You can change the size of the plots once they are pasted.

Print out this document and write in your work for computing the standard deviation and mean and also your name. Hand it in at the end of the class!