Sunday, January 14, 2007
Thursday, January 11, 2007
Statistics: Confidence intervals and Binomial
      We continued discussion of confidence intervals today, for 90%, 95%, and 99% confidence levels.  In addition, we talked about using the sample standard deviation instead of the population standard deviation in the formula for determining a confidence interval.
We also discussed properties of binomial experiments, what makes up a binomial experiment, and the difference between dependent and independent events.
The notes in the book for these two chapters are quite excellent and superior to any notes I could post here since they also come with explanations.
Homework is p. 205 #20,22,27 p. 211 #28,29,30 (assume sample size of 30) p.216 #1,2,3
There will be a quiz on Monday on ch.5.1, 5.2, and 5.3. A summary has been posted in class.
    We also discussed properties of binomial experiments, what makes up a binomial experiment, and the difference between dependent and independent events.
The notes in the book for these two chapters are quite excellent and superior to any notes I could post here since they also come with explanations.
Homework is p. 205 #20,22,27 p. 211 #28,29,30 (assume sample size of 30) p.216 #1,2,3
There will be a quiz on Monday on ch.5.1, 5.2, and 5.3. A summary has been posted in class.
Statistics: Confidence intervals
      We first discussed the interesting property of the Central Limit Theorem, in which you take any type of distribution, calculate the sample means, and those means are distributed normally.
Following, we looked at confidence intervals, p.202-205. Homework was p.207 #21 and 23.
    Following, we looked at confidence intervals, p.202-205. Homework was p.207 #21 and 23.
Tuesday, January 09, 2007
Statistics: Central Limit Theorem



Central Theorem, you can refer to the notes on the boards or the books.
If you are getting confused by terminology ("Mean of sample means ...") and the symbols in class I would highly recommend you take some time studying them (definitions in 5.3 and at the beginning of 5.1). It will definitely pay off in aiding your understanding. At this point, having put about a week into it, I am using them with the assumption that you are familiar and comfortable with them.
Friday, January 05, 2007
Statistics: Sample Distribution/ Sample Means
      No pictures today, sorry.  However, most of the work we did in class was covered in the text book, and the text book is actually quite good for this chapter.
p.187-190 'Sampling methods' - We talked about these for the first half of the double as well as working on questions 1-3, 5 on those pages. Descriptions for the different sampling methods are in the book.
p.191-192. We looked at taking samples of size 40 from a known population mean and population standard deviation. We took 6 samples using the graphing calculator, checked which was the closest to the sample mean, and which was the furthest. Someone in the class had a sample mean that was essentially equal to the pop. mean. Another person had a sample mean that had a difference of 8 for the population mean.
Taking the mean of these sample means have us a mean that was in most cases (but not all) closer to the population mean than any of their recorded data. To make it more accurate, we looked at collecting more samples.
p.193 we ran the command in procedure A (this will take 5-10 mins to run to completion). This essentially collects 100 different samples of size 40, and finds teh mean of each of them (using the known population mean and population standard deviation from the previous question). Homework is completing a Histogram of this data (you can use the bins on p.194).
    p.187-190 'Sampling methods' - We talked about these for the first half of the double as well as working on questions 1-3, 5 on those pages. Descriptions for the different sampling methods are in the book.
p.191-192. We looked at taking samples of size 40 from a known population mean and population standard deviation. We took 6 samples using the graphing calculator, checked which was the closest to the sample mean, and which was the furthest. Someone in the class had a sample mean that was essentially equal to the pop. mean. Another person had a sample mean that had a difference of 8 for the population mean.
Taking the mean of these sample means have us a mean that was in most cases (but not all) closer to the population mean than any of their recorded data. To make it more accurate, we looked at collecting more samples.
p.193 we ran the command in procedure A (this will take 5-10 mins to run to completion). This essentially collects 100 different samples of size 40, and finds teh mean of each of them (using the known population mean and population standard deviation from the previous question). Homework is completing a Histogram of this data (you can use the bins on p.194).












