×

### Let's log you in.

or

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

×

or

by: Cole Wojdacz

12

0

3

# Week 3 30002

Cole Wojdacz
KSU

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

×
Unlock Preview

These are the Week 3 lecture notes for Dr. Eng's Biostatistics class.
COURSE
Introductory biostatistics
PROF.
Dr. Eng
TYPE
Class Notes
PAGES
3
WORDS
CONCEPTS
Biostatistics
KARMA
25 ?

## Popular in Public Health

This 3 page Class Notes was uploaded by Cole Wojdacz on Tuesday February 2, 2016. The Class Notes belongs to 30002 at Kent State University taught by Dr. Eng in Summer 2015. Since its upload, it has received 12 views. For similar materials see Introductory biostatistics in Public Health at Kent State University.

×

## Reviews for Week 3

×

×

### What is Karma?

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

Date Created: 02/02/16
Basics of Probability Definition of Probability  Probability: reflects the likelihood than an outcome will occur o 0≤ probablity≤1 number wit houtcome o probability= N o P(outcomeoccurs)+P (outcomedoesn t occu)=1 N o P( )= a N  P() is read as "the probability of…"  A represents any event of interest  A-hat is the compliment of A or "not observing A"  N A is the number of events that meet the specified criterion  N is the total number of events The Addition Rule  If two or more events are mutually exclusive, we can find the probability that one of them happens by adding each of their probabilities Calculating Probabilities Contingency Tables  Contingency Table: a convenient means of summarizing data  Frequency Contingency Table: summarizes the numbers of observations in a data set that manifest some specified set of characteristics  Probability Contingency Table: summarizes the proportions of observations in a data set that manifest some specified set of characteristics Probability Notation  A ): the probability of observing event A P¿  P(AB) : the probability of observing event A and event B  P A∪B ) : the probability of observing event A or event B  P A B ): the probability of observing event A given that you have already observed event B Conditional Probability: probability of an outcome in a specific sub-population  A vertical line (|) = given o This makes it a conditional probability Independence  Independence: the outcome of one event doesn’t change the probabilities of the outcome of the other event Diagnostic Testing  The main goal is to accurately detect the presence of disease  Ideal diagnostic tests always correctly detect disease o They should also be simple, quick, cheap, reliable, safe, and painless o Many diagnostic tests do not meet these ideals  Evaluating diagnostic tests by using the test result as a predictor variable, and the actual disease rates as the outcome variable Definitions  Sensitivity: the probability of a positive test given the person has the disease o P(+¿ D)  Specificity: the probability of a negative test given that the person does not have the disease −¿D−¿ ¯ o P¿ Positive and Negative Predictive Values  Positive: the probability that a person who tests positive for a disease has that disease o D PPV=P¿  Negative: the probability that a person who tests negative for a disease does not have that disease o D−¿−¿ NPV=P¿ Risk Ratio and Odds Ratio Prevalence: the proportion of participants with a disease at a particular point in time  P(D)  Prevalence= number of personswithdisease number of personsexamined atbaseline Risk Ratio/Relative Risk (RR): formed by dividing the probability of disease in some group exposed to a potential risk factor by the probability of disease in some group not so exposed D |  P¿ P D |E) RR= ¿  Probability of disease in the exposed group: a o P(D|E = a+b  Probability of disease in the unexposed group: D o | P¿ Odds: the probability that the event will occur divided by the probability that the event will not occur  Odds of disease for the exposed group P D |E) o Odds= P (−¿E )  Odds of disease for the unexposed group D | E−¿¯ o ¿ D−¿E−¿ ¯ P¿ Odds=¿ Odds Ratio (OR): the odds of disease for an exposed group divided by the odds of disease for an unexposed group D |  P(D−¿E )P¿ ¯ ¿= P(D|E)P D−¿E−bar ) ¿ a  Odd E =b E−¿= c  d Od d¿

×

×

### BOOM! Enjoy Your Free Notes!

×

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

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."

Jennifer McGill UCSF Med School

#### "Selling my MCAT study guides and notes has been a great source of side revenue while I'm in school. Some months I'm making over \$500! Plus, it makes me happy knowing that I'm helping future med students with their MCAT."

Bentley McCaw University of Florida

#### "I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"

Parker Thompson 500 Startups

#### "It's a great way for students to improve their educational experience and it seemed like a product that everybody wants, so all the people participating are winning."

Become an Elite Notetaker and start selling your notes online!
×

### Refund Policy

#### STUDYSOUP CANCELLATION 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 support@studysoup.com

#### STUDYSOUP REFUND POLICY

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: support@studysoup.com

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 support@studysoup.com