Stat 2000: Tips for Assignment 1
Published: Fri, 09/23/11
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If you are taking the course by classroom lecture (Sections A01, A02, etc.), click here for my tips for your Assignment 1.
You need to study Lessons 1, 2 and 3 in my book (if you have it) to prepare for this assignment. I suggest you study Lesson 1, then attempt question 1. Study Lesson 2, then attempt question 2. You will need to study Lesson 3 before you are ready to attempt the rest of the assignment.
Question 1 is good run-through of all the concepts I teach in Lesson 1 of my book.
Question 2 has chosen an unusual level of confidence so be sure to study question 10 in Lesson 1 of my book to understand how to get the appropriate critical value. Make sure you have read the Appendix at the back of my book to learn how to use your calculator's Stat mode to get the mean and standard deviation of the data set (of course, you have been given the population standard deviation, so you don't really need the sample standard deviation). Lesson 2 in my book teaches you how to conduct a hypothesis test.
Never use JMP to answer a question unless they specifically tell you to. Whenever
they do tell you to use JMP, never go out of your way to click red
triangles to add things to the graph (like put titles on histograms, or
label axes). Whatever JMP gives by default is all they require unless
they specifically request you add something to the output or remove
something from it. Of course, I will always give you specific steps to
add/remove anything they do require.
To get JMP to make confidence intervals and test hypotheses for the mean:
First, open JMP and select "New Data Table". Double-click Column 1 and give it an appropriate name for the data set (like "weight"). Type the given data down column 1, using your Tab or Arrow keys on your keyboard to move down each cell.
Select Analyze,
Distribution from the toolbar at top. Highlight the column you are
interested in and click the "Y, Columns" button. Click OK. You are now
taken to a window showing a histogram and stuff.
To get a confidence
interval, click the red triangle next to your column variable directly
above the histogram to get a drop-down list and select "Confidence
Interval". In the pop-up window that appears, select "Other" (even if
the level of confidence you desire is in the list) and type in the level
of confidence you want (in decimal form, so 95% is 0.95). Make sure
"Two-sided" is selected. If you are given a value for sigma, the
population standard deviation, select the "Use known Sigma" checkbox.
Click OK. You will get another pop-up window where you can type in your
known value for sigma (if you selected that option). A Confidence
Intervals table will appear in your output screen at the bottom.
To
test a hypothesis, click that same red triangle you used to make a
confidence interval and select "Test Mean". Type in the value the null
hypothesis believes the mean to be and type in the known value of sigma
if you have one (otherwise leave that value blank). Click OK. A "Test
Mean = Value" table appears in your output where, among other things,
JMP gives you the test statistic and three probability values. Those
three probabilities are the P-value for the three possible alternative
hypotheses. JMP will use a z statistic if you are given a sigma value
to enter or a t statistic if sigma is unknown.
Prob > |z| or Prob > |t| is the two-tailed P-value.
Prob > z or Prob > t is the upper-tailed P-value.
Prob < z or Prob < t is the lower-tailed P-value.
Questions 3 to 6 are a good run-through of the concepts I teach in Lesson 3 of my book.
Questions 7 and 8 return to Lessons 1 and 2 in my book. (What is the key difference between these two questions the first two questions of the assignment?) See my tips above to help with the JMP part.
There is no distance/online course for Stat 2000 this term.