New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Math 109 Chapter 3 Note

by: tpnguy09

Math 109 Chapter 3 Note Math 109

Marketplace > University of Louisville > Mathmatics > Math 109 > Math 109 Chapter 3 Note
U of L

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Lecture 3 Notes
Elementary Statistics
Dr.Prasanna Sahoo
Class Notes
Math, Statistics
25 ?




Popular in Elementary Statistics

Popular in Mathmatics

This 4 page Class Notes was uploaded by tpnguy09 on Thursday September 1, 2016. The Class Notes belongs to Math 109 at University of Louisville taught by Dr.Prasanna Sahoo in Fall 2016. Since its upload, it has received 5 views. For similar materials see Elementary Statistics in Mathmatics at University of Louisville.


Reviews for Math 109 Chapter 3 Note


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 09/01/16
Review  Controlled experiment as well as observational studies are good methods for collecting data.  However, observational studies are not as successful as controlled experiment.  In a controlled experiment, the investigator decides who will be in the control group and who will be in the treatment group  In an observational study, the subjects assign themselves to one of these two groups. o The studies on  The effect of smoking  The sex discrimination on graduate admission  The racial discrimination in work place  The effect of spanking a child (can lower IQ  Are some examples of observational studies o In any observational study, confounding is a major source of bias o To avoid the effects of hidden confounding factors statisticians make comparisons separately for smaller and more homogenous groups  Compare gender to gender or age to age o In the UC, Berkeley example, we have seen that although the graduate school admitted 44% male applicants and 30% female applicants, the admission rate was because of the choice and not because of sex discrimination.  Compare major to major  Women decided to take harder majors than man Chapter 3  In 1973, fifty thousand American families were asked to report their incomes for the year 1972. The U.S. government received 50,000numbers o How do we examine and make sense out of 50,000 numb3ers? o Answer: summarize them. o To summarize data, statisticians often use a graph called a histogram.  A histogram consists of a set of blocks.  The ranges are called the class intervals  A histogram represents numbers by area, not height  The area of a block represents the percentage of the data that fall into the corresponding class interval.  Find the block u want, then do H x W  Reading a histogram o To learn how much data lies b/t two values, shade in the area above these values on the given histogram and estimate the area of the histogram that is shaded o Sometimes can draw curve (sketch) o If no vertical scale is given, estimate the area  How to draw a histogram o  Density Scale  A histogram is said to be in density scale if; o The height of each block is equal to the percentage of the data in that block divided by the width of that block o The units on the vertical axis are given in “% per horizontal unit” and o The total area of the histogram is 100%  If a histogram is in density scale, then, “lots of area implies lots of data points”  If a histogram is in the density scale, then the height of the histogram shows the crowding


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Anthony Lee UC Santa Barbara

"I bought an awesome study guide, which helped me get an A in my Math 34B class this quarter!"

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.