MATH221 all week discussions latest 2018 august

Week 1 discussion

DESCRIPTIVE STATISTICS

If you were given a large data set, such as the sales over the last year of our top 100 customers, what might you be able to do with these data? What might be the benefits of describing the data?

Week 2 discussion

REGRESSION

Suppose you are given data from a survey showing the IQ of each person interviewed and the IQ of his or her mother. That is all the information that you have. Your boss has asked you to put together a report showing the relationship between these two variables. What could you present and why?

Week 3 discussion

PROBABILITY AND ODDS

The odds of winning a game are given as 1:25. What is the probability that you will win this game? What is the probability that you will lose this game? In your follow up replies, consider which number in the odds ratio needs to change and how in order to increase the probability of winning. (Note: see page 145 in the text for a discussion on odds.)

Week 4 discussion

DISCRETE PROBABILITY VARIABLES

For this discussion you will use technology to create a short 1-2 minute multimedia post/presentation.

Suggestions: Narrated PowerPoint, recorded video (.mp4), VoiceThread, Screencast-O-Matic (.mp4), or a similar tool of your choice. Video can be recorded directly within a post as well, but make sure to plan out in advance what you are going to say/show. There should be a visual component as well as audio, so if you are using a webcam for the video that only shows you speaking, please attach your PowerPoint slide(s) (or screenshot images of them) to the post as well so everyone can see them.

In your short presentation, you will be describing an example that uses discrete probabilities or distributions. Provide an example that follows either the binomial or Poisson distribution, and explain why that example follows that particular distribution. In your responses to other students, make up numbers for the example provided by that other student, and ask a related probability question. Then show the work (or describe the technology steps) and solve that probability example.

For more information about Narrated PowerPoint or VoiceThread, see the General Resources section of Course Resources under the Introduction & Resources module heading. For all media posts in this course, please include a brief written synopsis to inform your classmates what the main point or purpose is that the linked, attached, or embedded media addresses.

Week 5 discussion

INTERPRETING NORMAL DISTRIBUTIONS

Assume that a population is normally distributed with a mean of 100 and a standard deviation of 15. Would it be unusual for the mean of a sample of 3 to be 115 or more? Why or why not?

Week 6 discussion

CONFIDENCE INTERVAL CONCEPTS

Consider the formula used for any confidence interval and the elements included in that formula. What happens to the confidence interval if you (a) increase the confidence level, (b) increase the sample size, or (c) increase the margin of error? Only consider one of these changes at a time. Explain your answer with words and by referencing the formula.

Week 7 discussion

REJECTION REGION

How is the rejection region defined, and how is that related to the p value? When do you reject or fail to reject the null hypothesis? Why do you think statisticians are asked to complete hypothesis testing? Can you think of examples in courts, in medicine, or in your area?