Did you read my tips on how to study and learn Stat 1000?  If not, here is a link to those important suggestions:

Did you read my Calculator Tips?  If not, here is a link to those important suggestions:

Don't have my book?  You can download a free sample containing Lesson 1 at my website here:

Do note that every time you exit a question in StatsPortal, the next time you return to it, the data may very well change.  Do not press the "back-up" button on your browser in a question.  That, too, will change the data.  When you are prepared to actually do a question, open the link, keep it open, and do not close it until you have submitted your answers.  There is also some debate whether even pressing "Save Answers" locks the data in place.

You should also have already downloaded the JMP statistical software which was provided with either one of the course options for StatsPortal as mentioned in your course outline.

Make sure you have gone through Assignment 0 completely to learn how to use the interface.  I also suggest you print out a copy of question 8 in Assignment 0 (Long Answer Questions - Part 3) so that you have the steps for saving and uploading files into the HTML editor in front of you.

This is a standard question about classifying variables, similar to my question 1 in Lesson 1.

This deals with some aspects of quantitative distributions.  Note that part (a) wants a decimal, not a percent.  For example, if you figured out that 20/30 are in this interval, 20 divide by 30 is 0.6667, not 66.6667%. 

Remember that a frequency table is a precursor to a histogram.  Visualize the histogram (don't actually make a histogram, just picture it) to help answer the questions.  Remember, quartiles break the data up into 25% sections.  You cannot actually compute the median, mean or quartiles because you do not have the actual data.  You don't need to.  The shape of the distribution is enough to know if the mean is larger, smaller or the same as the median.  And, you do know the sample size, n, (the total count in the Frequency column), so you can use the steps I teach in Lesson 1 to find the location of any quartile .  Then just count through the intervals.  You know how much data is in the first interval, second interval, etc., so you know which interval must contain the first, second or third quartile.

Do not use JMP for the stemplot in part (a).  You can just type the stemplot directly into the text box they provide.  Note that you are told to trim the leaves.  That means that you cut away the last digit (don't round off, just cut it off as though it was never there in the first place).  For example, 177 would be trimmed to 17, not rounded off to 18.

I suggest you make the split stemplot on paper first, then transfer it to the box.  Make sure you click "HTML Editor" below the box before you type anything in.

Use the vertical line on your computer keyboard to separate the stem from the leaves ("SHIFT \" will give you " | ").  Don't worry if your columns don't end up perfectly lined up, just do the best you can.  Be sure to label the first line in your stemplot "Stem | Leaf", then enter all the stems and leaves row-by-row underneath.  Don't forget to comment on the shape of the distribution (peaks, symmetric, left-skewed, right-skewed, outliers.)

Don't forget to answer part (b) in the HTML editor box, too.

To make the histogram in part (c):
First, enter the data into JMP manually: Click the "New Data Table" icon on the toolbar at top left in the JMP home screen (or select "File" in the toolbar, then New, then Data Table).  You are automatically taken to an empty spreadsheet with one column. Double-click "Column 1" and change its name to "Energy", or right-click "Column 1" and select "Column Info" and type in the name "Energy" and click OK.  Type your data down the column.  Note you can use your arrow buttons or TAB to move from one cell to the next as you enter your data.

Once you have entered all the data down your columns, you are ready to make your histogram.  In the toolbar at the top, select Analyze then select Distribution.  In the "Select Columns" part of the pop-up window, click the column you want the histogram for ("Energy" in this case) to highlight it, and click the Y, Columns button.  You should see the "Energy" column appear in the section to the right of the "Y, Columns" button.  Click OK.

It now opens yet another pop-up window called "Distributions" where your histogram should appear.  Your histogram appears sideways. They want to see it the typical way, so click the red triangle next to "Energy" above the histogram and select Histogram Options from the drop-down menu.  Deselect "Vertical" and it will turn it the proper way (horizontal layout).

If you want to hide all the other parts of the output (but they said you don't have to), click that same red triangle again and deselect "Outlier Box Plot" and anything else that has a check mark next to it.  Click the red triangle again, select "Display Options" and deselect "Quantiles" and "Summary Statistics" to make those parts disappear.  Alternatively, you can make the Quantiles and Summary Statistics disappear if you simply click the gray triangles (to the left of the red triangles) next to their title bars.  Click the gray triangles again to make them reappear.

• If you are using Windows:
• Press "Alt" on your keyboard or click the thin blue line that is near the top of the window to get the toolbar icons to appear.  Select "File" then "Save As" to get a pop-up window.  Type in whatever name you want the file to have in the "File name" section. Click the "Browse Folders" arrow and select which folder you want to save the file in (I suggest you select "Desktop" so that the file will just appear right on your desktop home screen).  Finally, click the drop down arrow in the "Save as type" section and select "JPEG File".  Click "Save".  You should now have your file ready to upload into the assignment.
• To upload your file into the text box they provide: Click "HTML editor" below the text box (if you have not already done so) to make a toolbar appear in the text box.  Click the toolbar option called "Link" and select "Image."  In the pop-up window that appears, click the button called "Find/Upload File" (it is at the bottom of the pop-up window, you may have to enlarge the box or scroll down to see it).  Click the "Browse" button and find the histogram file you just saved.  Either double-click that file or select it and click "Open" and you should see the path to that file appear in the Browse box.  Click "Upload File" and its name should appear in the "Uploaded Files" pop-up window.  Select the file in the list of "Uploaded Files" to highlight it and click OK and you should see the file appear in the text box. 

• If you are using Apple/Mac:
• You will need to take a screen shot of your output in order to upload it.  To take a screen shot hold down Command+Shift+4 and drag the cross-hairs over the image to capture it.  The image will save a .png file to your desktop by default.
• To upload your file into the text box they provide: Click "HTML editor" below the text box (if you have not already done so) to make a toolbar appear in the text box.  Click the toolbar option called "Link" and select "Image."  In the pop-up window that appears, click the button called "Find/Upload File" (it is at the bottom of the pop-up window, you may have to enlarge the box or scroll down to see it).  Click the "Browse" button and find the histogram file you just saved.  Either double-click that file or select it and click "Open" and you should see the path to that file appear in the Browse box.  Click "Upload File" and its name should appear in the "Uploaded Files" pop-up window.  Select the file in the list of "Uploaded Files" to highlight it and click OK and you should see the file appear in the text box.

Type your answer to part (d) in the box.

To make the Time Series in part (e):
First, you will have to open a new data table in JMP.  Don't even waste your time typing "Jan 2011," Feb 2011," etc. down a column. JMP won't be able to do anything with it anyway. (There is a way to type in month and year dates in a column for a time series but it is very complicated, and the steps you are given in the actual question suggest they don't want it done anyway.

Instead, simply double-click Column 1 and rename that column "Monthly Energy."  Type in the energy data you have been given.

You are now ready to make the time series.  Select Analyze in the toolbar, then select Modeling in the drop-down list and finally select time series.  Select the variable you are tracking "Monthly Energy " and click "Y, Time Series".  Click OK.  Just ignore that other pop-up menu asking about time lags or autocorrelations or whatever, click OK and move on.  None of that has anything to do with the time series.

You should now be looking at your Time Series with "Row" on the horizontal axis and "Monthly Energy" on the vertical axis.  Click the red triangle next to "Time Series Price" and deselect "Autocorrelation" and "Partial Autocorrelation" to remove those parts of the output.  Click the red triangle again, select "Graph" then deselect "Mean Line".  That removes the horizontal line in your time series showing the mean points score.

Optional: They don't ask you to do this, but since the horizontal axis isn't very descriptive (merely numbering from 1 to 25 rather than showing the dates given in the data table), you could double-click where it says "Row" below the horizontal axis on the graph, and name it something more applicable, like Month or "Jan 2011 to Dec 2012" perhaps.  Then, again, you can just leave it as "Row" since they never asked you to change it.

• If you are using Windows:
• Press "Alt" on your keyboard or click the thin blue line that is near the top of the window to get the toolbar icons to appear.  Select "File" then "Save As" to get a pop-up window.  Type in whatever name you want the file to have in the "File name" section. Click the "Browse Folders" arrow and select which folder you want to save the file in (I suggest you select "Desktop" so that the file will just appear right on your desktop home screen).  Finally, click the drop down arrow in the "Save as type" section and select "JPEG File".  Click "Save".  You should now have your file ready to upload into the assignment.
• To upload your file into the text box they provide: Click "HTML editor" below the text box (if you have not already done so) to make a toolbar appear in the text box.  Click the toolbar option called "Link" and select "Image."  In the pop-up window that appears, click the button called "Find/Upload File" (it is at the bottom of the pop-up window, you may have to enlarge the box or scroll down to see it).  Click the "Browse" button and find the time series file you just saved.  Either double-click that file or select it and click "Open" and you should see the path to that file appear in the Browse box.  Click "Upload File" and its name should appear in the "Uploaded Files" pop-up window.  Select the file in the list of "Uploaded Files" to highlight it and click OK and you should see the file appear in the text box. 

• If you are using Apple/Mac:
• You will need to take a screen shot of your output in order to upload it.  To take a screen shot hold down Command+Shift+4 and drag the cross-hairs over the image to capture it.  The image will save a .png file to your desktop by default.
• To upload your file into the text box they provide: Click "HTML editor" below the text box (if you have not already done so) to make a toolbar appear in the text box.  Click the toolbar option called "Link" and select "Image."  In the pop-up window that appears, click the button called "Find/Upload File" (it is at the bottom of the pop-up window, you may have to enlarge the box or scroll down to see it).  Click the "Browse" button and find the time series file you just saved.  Either double-click that file or select it and click "Open" and you should see the path to that file appear in the Browse box.  Click "Upload File" and its name should appear in the "Uploaded Files" pop-up window.  Select the file in the list of "Uploaded Files" to highlight it and click OK and you should see the file appear in the text box.

Type your answer to part (f) in the box.   Take a look at my question 3 in Lesson 1 for an example of a time series and how to describe.  Is there a trend?  Did the trend change at some point?  If so, when?  Is there perhaps a seasonal variation?  If so, what is that variation?  These are the kinds of questions you ask yourself when describing a time series.

Open a "New Data Table" in JMP.  You will make two columns, but not the way you might think. DO NOT put the Consumer Stocks in one column and the Technology Stocks in another!

Double-click Column 1 (or right-click and select Column Info) and name it "Return".  Type all 13 returns from the Consumer Stocks followed by the 17 returns from the Technology Stocks giving you a total of 30 rows in the first column. Double-click the region to the right of Column 1 at the top to create Column 2 and name that column "Sector ."  Type "Consumer" in the first thirteen rows of that column (better yet, type it once, copy and paste it into the next twelve rows; that way you ensure it is typed exactly the same in all thirteen rows as is necessary).  Then type (or copy and paste) "Technology" in the remaining rows of column 2.

To make the side-by-side boxplots:
Select "Analyze" then "Fit Y By X".  Highlight "Return" and click "Y, Response".  Highlight "Sector" and click "X, Factor".  Click OK.  This should open a pop-up window with a bunch of dots arranged vertically on a graph for "Consumer" and  "Technology".  If  that does not happen, return to the data table and double-click each column (or right-click and select column info).  The Return column better have Data Type as "numeric" and Modeling Type as "continuous ."  Change those settings if not.  The Sector column column better have Data Type as "character" and Modeling Type as "nominal."  Change those settings if not.

Now click the red triangle next to "Oneway Analysis ..." and select "Quantiles."  Your side-by-side box plots should appear on the graph as well as a Quantiles output below that shows you the five-number summary among other things.  Click the red triangle again and select "Display Options" (down near the bottom of the menu), then deselect "Grand Mean" to get rid of the horizontal line in the graph showing the mean of all the scores.  Click the red triangle once more, select Display Options again, and deselect "Points" to remove the data points on the graph.

• If you are using Windows:
• Press "Alt" on your keyboard or click the thin blue line that is near the top of the window to get the toolbar icons to appear.  Select "File" then "Save As" to get a pop-up window.  Type in whatever name you want the file to have in the "File name" section. Click the "Browse Folders" arrow and select which folder you want to save the file in (I suggest you select "Desktop" so that the file will just appear right on your desktop home screen).  Finally, click the drop down arrow in the "Save as type" section and select "JPEG File".  Click "Save".  You should now have your file ready to upload into the assignment.
• To upload your file into the text box they provide: Click "HTML editor" below the text box (if you have not already done so) to make a toolbar appear in the text box.  Click the toolbar option called "Link" and select "Image."  In the pop-up window that appears, click the button called "Find/Upload File" (it is at the bottom of the pop-up window, you may have to enlarge the box or scroll down to see it).  Click the "Browse" button and find the boxplots file you just saved.  Either double-click that file or select it and click "Open" and you should see the path to that file appear in the Browse box.  Click "Upload File" and its name should appear in the "Uploaded Files" pop-up window.  Select the file in the list of "Uploaded Files" to highlight it and click OK and you should see the file appear in the text box. 

• If you are using Apple/Mac:
• You will need to take a screen shot of your output in order to upload it.  To take a screen shot hold down Command+Shift+4 and drag the cross-hairs over the image to capture it.  The image will save a .png file to your desktop by default.
• To upload your file into the text box they provide: Click "HTML editor" below the text box (if you have not already done so) to make a toolbar appear in the text box.  Click the toolbar option called "Link" and select "Image."  In the pop-up window that appears, click the button called "Find/Upload File" (it is at the bottom of the pop-up window, you may have to enlarge the box or scroll down to see it).  Click the "Browse" button and find the boxplots file you just saved.  Either double-click that file or select it and click "Open" and you should see the path to that file appear in the Browse box.  Click "Upload File" and its name should appear in the "Uploaded Files" pop-up window.  Select the file in the list of "Uploaded Files" to highlight it and click OK and you should see the file appear in the text box.
  

Type your answers to parts (b), (c) and (d) directly into the text box.

This question is to be done by hand. Note that part (b) wants you to mis-read the skew or symmetry by looking at the whiskers' full length, regardless if there are outliers or not.  They give you the chance to properly describe the shape later, after you have done a modified boxplot.  Make sure you have gone through question 4 in my Lesson 1 before doing this question.  (Of course, as i said in a previous email, you should have thoroughly studied all of Lesson 1 before doing this assignment.  Learn first, then apply your knowledge in the assignment.

This question should be done by hand (i.e. with your calculator, not with JMP).  Use the Stat Mode on your calculator to compute the Mean and Standard Deviation.  Check the Appendix at the back of my book to learn how to use the Stat Mode on your calculator.  Here is a link to a digital copy of that appendix:

Part (c) is introducing a key concept about changing the units in data.  Be sure to read the "Effect of Changing Units on Centre and Spread" section of my book in Lesson 1 and see questions 17 and 18 for examples.  As they say, once you know the mean and standard deviation from parts (a) and (b), you can convert them into the mean and standard deviation for part (c) using the conversion formula they gave you at the start.  But do it properly!  Remember, you apply the formula differently depending on whether you are converting a measure of centre or a measure of spread.

For part (d), consider this:  Let's say you are taking a course, and your average mark so far is 65.  What will happen to your average if you score higher on the next test?  What if you score lower on the next test?  What would you have to get on the next test to have your average stay 65?

For part (e), having decided what that ninth score must be in part (d), how much does that score deviate from the mean? If that is a larger deviation than the standard deviation you computed earlier, you have increased the overall standard deviation; if it is the same amount of deviation as earlier, you have not changed the standard deviation at all; if it has a smaller deviation, you have decreased your overall standard deviation.

First, you need to know the scores attached to each letter grade.  An A+ is 4.5, A is 4, B+ is 3.5, B is 3, etc.

To compute your grade point average:
First, make a new column where you multiply each grade score by the number of credit hours.  For example, if you got a B+ in a 3 credit-hour course, you would multiply 3.5 by 3 to get 10.5 in this new column. Find the total of this new column and find the total number of credit hours.  Divide the total of the new column by the total number of credit hours to get the GPA.  Put another way, if you got a B+ in 3 credit-hour course, it is as though you scored 3.5 three separate times.  You could put your calculator in Stat Mode, and enter 3.5 in three separate times.  If you got an A in a 6 credit-hour course, you got 4.0 six times.  Enter 4.0 six separate times.  After you have entered all the data, your calculator will tell you the mean (your GPA).

An easy way to think of grade points is to consider the amount of credit hours as the frequency of that grade.  Gettting an A in a 3-credit hour course, is like getting an A 3 separate times.  Getting a C in a 6-credit hour course is like getting a C 6 separate times.  It is like finding the average of three A's and six C's.