### Create a StudySoup account

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

Already have a StudySoup account? Login here

# STA 3123 FINAL EXAM REVIEW STA 3123- Statistics for Behavioral and Social Sciences

FIU

GPA 4.0

### View Full Document

## 812

## 1

## Popular in Statistics for Behavioral and Social Sciences

###### Study Guide

##### STA 3123- Statistics for Behavioral and Social Sciences

###### Sheyla Moliner

verified elite notetaker

## Popular in Mathematics (M)

This 11 page Study Guide was uploaded by Sheyla Moliner on Wednesday January 7, 2015. The Study Guide belongs to STA 3123- Statistics for Behavioral and Social Sciences at Florida International University taught by Dane Mcguckian in Winter2015. Since its upload, it has received 812 views. For similar materials see Statistics for Behavioral and Social Sciences in Mathematics (M) at Florida International University.

## Similar to STA 3123- Statistics for Behavioral and Social Sciences at FIU

## Popular in Mathematics (M)

## Reviews for STA 3123 FINAL EXAM REVIEW

### 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: 01/07/15

STA3123 Final Exam Review Supplement Homework Problems to Review for the Final Chapter 7 problems 9 10 23 and 64 9 A 99 con dence interval was constructed to estimate the mean and the resulting interval is 968 1102 Write a statement to correctly interpret the interval 10lnterpret the con dence coef cient used in problem 9 In other words what does it mean to say we are 99 con dent 23Again the standard deviation is large what effect will this have on the margin of error How can this effect be countered Or decrease the con dence level 64 A company claims that they have a method for preselecting your child s eye color Out of 2000 couples trying to have a child with blue eyes 510 of them had a baby with blue eyes after undergoing the procedure The company claims this is a success but a researcher pointed out that these couples had a 25 chance of having a blue eyed baby simply due to the genes they already carried Form a 98 con dence interval to estimate the true proportion of similar parents that would give birth to a blue eyed child after using the company39s services Can we conclude the company39s methods produce more than a 25 success rate Chapter 8 problems 15 17 37 39 47 49 150riginal claim The average grade in the class is a 76 Initial Conclusion Reject the null 170riginal claim The average time to nish exam one is less than 75 minutes Initial Conclusion Reject the null 37 The CEO of Equifax credit reporting agency claims the average credit rating has dropped below 675 points A study of 20 randomly selected credit scores had an average of 660 points and a standard deviation of 953 points Use a 5 signi cance level to test the claim that credit scores are now on average below 675 points The CEO claims the results are not valid since they came from too small a sample Is there any merit to his argument 39 A female student of mine claims that the average height of female super models is the same as the average for women in general 64 inches I randomly selected 9 supermodels from a list of super models and found they had an average height of 702 inches with a standard deviation of 25 inches Use a 1 signi cance level to test my student s claim If she disputes the result of the test by arguing that I took too small a sample is there some merit to her argument 47 If you have a signi cance level of 1 and a pvalue of 00238 after forming the appropriate conclusion what possible error might you have committed Type one or two Explain 48 If you are testing the claim u gt 96 and your signi cance level is 8 what is the probability that you commit the type one error 49 If you are testing the claim u200 and your signi cance level is 5 what is the probability that you commit the type one error Chapter 9 problems 6 8 37 6 A large sample confidence interval for the true average difference between IQ s of male students and female students was created The result was as follows 11 lt um u f lt 9 Is there a significant difference Which group had the larger sample mean 7 A large sample con dence interval for the true average difference between the maximum bench press of eighteen year old males and 25 year old males in the US army was created The result was as follows 21 lt i118 u25 lt 19 Is there a signi cant difference Which group had the larger sample mean 9 A large sample confidence interval for the true average difference between vertical leap of male track athletes and the vertical leap female track athletes was created The result was as follows 3 lt um u f lt 5 Is there a significant difference Which group had the larger sample mean 37 One of the skills that is necessary in order for you to be able to use the statistical techniques learned in this class is the ability to recognize when a particular test is appropriate For example what makes the scenario in the question above a matched pairs ttest as opposed to an independent ttest Chapter 10 problems 11 19 Chapter 11 problems 3 4 13 15 38 39 41 45 47 3 What does x 0 represent 4 What average grade does the model predict for students who have perfect attendance 267696788076 Example Solution 13 Why do we say that the least squares line provides the best fit of any linear model 14 What is the sum of all the errors 2y y made by any least squares line 15 A researcher collected data involving the frequency of chirps made by a ground cricket at various ground temperatures He showed that there was a significant linear relationship between temperature and the frequency of chirps The data he used is below Would it be a good idea to use the model to estimate the average chirp frequency when the temperature was 51 degrees Why or why not VS 38 A study looking for a relationship between the area of the skin covered in tattoos and the number of sexual partners finds a correlation coefficient r 0987 What does this indicate 39 A study looking at the demand for high speed internet and the price of the service finds that the correlation coefficient for the sample data is r 0012 What does this indicate 41Cacuate the coef cient of determination r2 for the problem above and interpret it 45 Calculate the coef cient of determination r2 for the problem above and interpret it 47 If we are told the coef cient of determination is r2 0928 can we know what r is just by taking the square root If not why assume simple linear regression was done with one predictor variable X Chapter 14 problems 10 and 13 10 True or False In general nonparametric tests are less powerful than our parametric tests 13l39m a little surprised by this result so I argue that I couldn39t reject the null because the sign test is such a weak test Is there any validity to this argument Find the connections in the methods we learned For example which methods were used with one sample of data Which methods are used with two samples of data Which of the above are for independent samples What methods did we learn to deal with three or more samples STA3123 Final Exam Review Supplement What methods deal with proportions Do you see what is similar about the list above for proportions and the one below ttest Independent ttest and ANOVA CRD Try this one The Independent ttest is to the Matched Pairs ttest as the ANOVA CRD all the means are same is to Try this one A researcher wants to know if the proportion of BMW owners who are male is higher than the proportion of BMW owners who are female Which procedure have we learned to test this kind of hypothesis EXAMPLES OF THE FTEST AND INDEPENDENT TEST A researcher theorized that average heights of boys and girls of the same age prior to undergoing puberty should be the same Fiftyeight randomly selected boys of age 8 had an average height of 1235 cm with a variance of 98cm Fiftyfive randomly selected girls had an average height of 1261 cm with a variance of 119cm Use a 1 significance level and the pvalue method to test the claim that there is no difference between the average heights of boys and girls at age eight Is there a difference between the variances of the number of weeks on the best seller lists for non ction and ction books Fifteen New York Times bestselling ction books had a standard deviation of 617 weeks on the list Sixteen New York Times bestselling non ction books had a standard deviation of 1312 weeks At the 10 signi cance level can we conclude there is a difference in the variances Questions on test A Type I error is the mistake of rejecting the null hypothesis when it is true A Type II error is the mistake of failing to reject the null hypothesis when it is false In hypothesis testing we want to make sure the worst of the two possible errors is the type I error The reason for this is that we design the test to control the probability of the type one error The below table explains how the signi cance level is related to the type one error To reduce the error rate for a type one error we lower the signi cance level alpha or but this will increase the likelihood of committing a type II error To reduce the error rate for both a type one error and a type two error we need to increase the sample size and lower the signi cance level or Method Conditions 6 known amp normally distributed or Zdlstrlbutlon 6 known amp n gt 30 a not known amp normally distributed or tdlstrlbutlon 6 not known amp n gt 30 Population is not normally distributed Nonparametri and c nSBO LOOK AT EXAMS Kruskal walls is alike ANOVA CRD the difference is the walls is non parametric Frideman fr is like ANOVA RBD Wilconcin sum rank test independent t test Wilxcon sign rank dependent t test Dependent dependent t test Wilcoxon signed rank test anything with blocking The variances is always the f test Chapter 13 3 or more populations chisquare goodness of t ANOVA for proportions Chi square test of independence Chapter 11 linear regression no causality correLa tion does not mean causation Why used least square ine smallest sum of square error SSE minimum and the sum of error is SE zero Rquot2 the percent of variation in y that can be explained by x If you reject the null in a ANOVA that means you reject the fact that they are all the same and vice versa Section 87 Type one and type two error videos that might be helpful Chapter 7 Example 105 from 557 to the end Chapter 8 Type amp Type II error in the lecture example section Example 127 Example 1305 STA3123 Final Exam Review Supplement 85 problems 1 and 3 87 problems 1 3 Sample Exam 1 problems 5 7 Chapter 9 91 concept 2 problems 4 6 Sample Exam 2 problems 2 3 6 9 14 15 16 and 19 Chapter 10 Example Videos 154 155 156 157 and 1575 102 all of the videos Chapter 11 Example 169 from 321 to the end A Complete Example from the lecture example section 111 problems 5 116 concept video and problem 4 117 concept video problem 3 just the interpretation and problem 4 Sample Exam 3 problems 6 8 11 14 and 18 Chapter 13 Example 181 Chapter 14 144 concept 1 145 concept video just the big picture idea about what the test is used for 146 concept video just the big picture idea about what the test is used for 147 concept video just the big picture idea about what the test is used for 148 concept video just the big picture idea about what the test is used for Sample Exam 4 problems 6 and 19

### 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

#### "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."

#### "I signed up to be an Elite Notetaker with 2 of my sorority sisters this semester. We just posted our notes weekly and were each making over $600 per month. I LOVE StudySoup!"

#### "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."

#### "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."

### 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

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.