Stats 2 tips
F test notes
You can use the F test to verify a claim about a standard deviation (or variance) for 2 data sets. Assumptions: The sample is from a "normal distribution" NOTE: some professors prefer to use the following notation: N~(mean, Standard Deviation) Writing the hypothesis: H_{0}: population standard deviation_{1} = population standard deviation_{2} H_{1}: population standard deviation_{1 }is less than, greater than, or not equal to population standard deviation_{2} Critical Value = shaded area from F table using the degrees of freedom. Degrees of freedom: for numerator (use the info from the bigger Standard Deviation) n1, for denominator (use the info from the smaller Standard Deviation) n1. Remember that if the null hypothesis requires two tails, split the alpha before using the tables. Test statistic formula: F = variance_{1} / variance_{2}^{ } **The bigger variance (standard deviation squared) must be divided by the smaller variance (standard deviation squared).** Calculator: Press STAT Highlight TESTS Select 2SampFTest Put your information in. **NOTE: S_{1} must be the biggest standard deviation** Make sure the not equal to, less than, or greater than symbol matches the one in your alternative hypothesis (H_{1}). Highlight Calculate Press ENTER F is the test statistic, and P is the Pvalue. Rejection of the null hypothesis (Ho): You can reject the null hypothesis if:
Remember: if you are not given an alpha assume you are using 0.05. 
Hypothesis testing workshop
Hi everyone,
There will be a workshop on hypothesis testing on Thursday OCT 21,2010 from 2:30 to 3:30 in the IRC Room 116.
Click here to RSVP for a seat and free candy.
Patty
If the link doesn't work try this one: http://www.zoomerang.com/Survey/WEB22BAPG6V8E7 
Confidence intervals
Welcome back, the first sections of Stats 2 will cover a
review of stats one and an introduction to the confidence interval. Not only is
it important that you understand how to create a confidence interval but you must be able to translate their meaning
from stats into everyday english. In short, a confidence interval is found via
a formula and states that within a certain amount of error (E) you can be
certain that your data should fall between two numbers. I've attached an example of how to create a confidence interval.

Happy summer everyone!
Happy summer everyone!
Heads up, this is the material you need to remember if you're planning on starting Stats 2 this semester.
Review descriptive statistics, basic graphs (histogram, box plot, stem & leaf, cumulative frequency polygon), normal curve, central limit theorem. Might want to also do assessing normality (section 62). 
Which formula to use:

Population or Sample
"Samples are small, & they're written in English. Populations are general, & they're written in Greek." All sample (portions of the whole group) data is written using english letters. Whereas, the majority of population data use Greek notation. 