Welcome to Statistics II

Andy Novocin

High Intensity Schedule

52 Hours of instruction in 5 weeks

3 Tests

33 HW assignments

15 Lab assignments

5 Data Analysis Assignments

Syllabus Link

at stats.prof.ninja

Statistics in Business

When money is on the line you can't afford delusions

If you are reporting to a manager or being reported to you'll want to set the right tone.

When the stakes are high...

Decision making with averages only:

You bought a new super-truck for doing deliveries between Chicago and Texas. It is 12 feet tall. The average overpass in Illinois is 12.5 feet tall...

The decision maker needs to know the distribution.


The conclusion needs careful wording.


An assessment of confidence is important.

Generalization


With huge numbers of units in a population we have to sample.


Understanding how to convert sample data to general truths about the population distribution is a central aim of both 201 and 202.


If the sample is not taken randomly from the population then your conclusions are probably not valid.

Randomness is KEY

Cause and Effect


We want to know if some particular factors have an impact on a statistic.


This theme will show up in several formats in our course.


If you do not randomly assign treatments to your units then your conclusions are probably not valid.

In Class Groups


I want to take frequent breaks during lectures.


During a break I want you to work problems with a nearby group of students.


Help each other understand, and I can address and correct issues that pop up.


If this doesn't work well, I will drop the practice.

Review Topics


Confidence Intervals for Single Sample Inferences


Hypothesis Testing for Single Sample Inferences

The Inferences We Address:


Mean


Proportion


Variance

The sample size is either:


Small


or Large

For those counting that is 12 setups so far:


Confidence Interval vs. Test Statistic


Small Sample vs Large Sample


Mean vs Proportion vs Variance

I Love The Flow Charts


Pg 342 and Pg 408


Find your group and work 6.105-6.109 and 7.108-7.117


If there is a tough one ask me and I'll work it for everyone