×

### Let's log you in.

or

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

×

or

## Exam for chapter 2+1 Study Guide

by: Brittany Wittrock

61

0

3

# Exam for chapter 2+1 Study Guide STAT 239

Marketplace > St. Cloud State University > Statistics > STAT 239 > Exam for chapter 2 1 Study Guide
Brittany Wittrock
SCSU
GPA 4.0
Statistics for the Biological and Physical Sciences
Ernst, Michael

These notes were just uploaded, and will be ready to view shortly.

Either way, we'll remind you when they're ready :)

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

×
Unlock Preview

Definitions and equations along with other notes pertaining to the first two chapters of "Statistics Unlocking the Power of Data" By Loch.
COURSE
Statistics for the Biological and Physical Sciences
PROF.
Ernst, Michael
TYPE
Study Guide
PAGES
3
WORDS
KARMA
50 ?

## Popular in Statistics

This 3 page Study Guide was uploaded by Brittany Wittrock on Friday September 11, 2015. The Study Guide belongs to STAT 239 at St. Cloud State University taught by Ernst, Michael in Fall 2015. Since its upload, it has received 61 views. For similar materials see Statistics for the Biological and Physical Sciences in Statistics at St. Cloud State University.

×

## Reviews for Exam for chapter 2+1 Study Guide

×

×

### 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: 09/11/15
Statistics 239 summary of notes for final exam Study Guide Chapter 1 Statistics science of collecting describing and analyzing data Variable any characteristic that is recorded for each case Categorical divides into groups placing each in one of two or more categoriesoptions Quantitative measuring numerically for each case Population all individuals or objects of interest Sample subset of population Statistical Inference process of using data from a sample to gain information about the population Sampling Bias occurs when the method of selecting the sample causes the sample to differ from the population Simple Random Sampling n units all groups of size n in the population have the same chance of becoming sample Bias exists when the method of collecting data causes the sample data in inaccurately re ect the population Explanatory Variable what is being tested Response Variable what result is looked for cannot get a random by picking and choosing Associated two variables are associated if values of one variable tend to relate to the values of the other Causally Associated changing the value of one variable in uences the value of the other variable Confounding VariableFactorLurking Variable is a third variable that is associated with both the explanatory and response variables Plausible association between two variables of interest Direct In uence Experiment is a study where the researcher controls one or more explanatory variables Observational Study Researcher has no control over any variablesimply observes rarely used to establish causality Randomized Experiments value of explanatory variable for each unit is determined randomly before the response variable is measured Randomized Comparative Experiment randomly assign cases to different treatment groups then compare results of response variables Matched Pairs Experiment each case gets both treatments in random order and we examine individual differences in the response variable between the two treatments Chapter 2 Summary Statistics visualizing data into graphs and see how to summarize key aspects of the data using numerical quantities Proportion proportionnumber in that categorytotal percentage for a sample it is represented by phat xtotaly population prho xtotaly Twoway Table used to show the relationship between two categorical variables Dotplot common way to visualize the shape of a moderately sized data set Outlier is an observed value that is notably distinct from other values in a data set Shapes for distribution Symmetric two sides match when folded down the center Skewed Right data is piled to the left and tail extends to the right Skewed Left data is piled to the right and tail extends to the left BellShaped data is symmetric and looks like a bell Mean meansum of all data valuesnumber of data values sample xbar population mue Mediansummarize the center of a set of numbers middle entry if odd average of two numbers if even of entries sample m Resistance related to the impact of outliers on a statistic median is resistant mean is not resistant is relatively unaffected by extreme values Standard Deviation for quantitative variables measures the spread of the data in a sample s pth percentile value of quantitative variable which is greater than P percent of the data Five Number Summary minimum Q1 Median Q3 Max Qquartiles Range rangemaximumminimum Interquartile Range IQRQ3Q1 Boxplot See page 91 in Statistics Unlocking the Power of Data Outlier smaller than Q115IQR or greater than Q315IQR Sidebyside graphs used to visualize the relationship between a quantitative variable and a categorical variable 2 score fancy zXXbars calculating outliers Scatter Plot graph showing the relationship between two quantitative variables Properties of the correlation The sample correlation r has the following properties Always between 1 and 1 inclusive Values close to either side show a strong linear relationship Numbers close to zero show little to no linear relationship The correlation r has no units and is independent of the scale of either variable The correlation is symmetriccorrelation between X and y are same as that of y and X The population correlation p also ful ls these properties Sample r Population p Cautions for Correlations 1 strong or relationships don t necessarily imply a cause and effect relationship 2 near zero correlation doesn t necessarily mean the variables are not associated only measures linear relationship 3 correlation can be heavily in uenced by outliersplot your data Regression lineslope for graphs YhatabX Response a bEXplanatory

×

×

### 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."

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."

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