Exam 6: Probability

Researchers in health and advertising are interested in looking at how alternative forms of alcohol advertising are related to actual alcohol use among youth.Imagine you have conducted a study looking at the relationship between owning an item that advertises alcohol (such as a hat,t-shirt or cup with an alcohol logo on it)and having tried alcohol among a group of 12-year-olds.You observe 500 cases total.Of those 500 cases,100 have tried alcohol.For the 100 cases who have tried alcohol,32 own an item that advertises alcohol.You wish to address the following research question: Is the observation that 32 out of 100 youths who have tried alcohol own an advertising item sufficient evidence to say that these two factors are related? What is the probability of obtaining a z score of 2.80?

Using the example of a coin flip,distinguish between a trial and an event.

A marketing researcher at a computer company did a study examining user satisfaction with two operating systems.A total of 300 users were surveyed on the type of operating system used and their satisfaction with it.Use the following data set to answer questions 6-14: Using sampling with replacement,what is the probability of randomly selecting someone who is satisfied with system 10,and then randomly selecting someone who is satisfied with system 9?

A researcher wanted to compare eye color distributions of babies born with a birth defect with babies who did not have the birth defect.26 babies with the defect were matched on gender,race,and age with 52 babies without the defect.The frequency of different eye colors as a function of the presence or absence of the defects was as follows: Eye Color Group Dark Medium Light Defect 1 6 19 No Defect 15 13 24 The probability of the number of observations favoring both events A and B,divided by the total number of observations,is called a ____ probability.

A marketing researcher at a computer company did a study examining user satisfaction with two operating systems.A total of 300 users were surveyed on the type of operating system used and their satisfaction with it.Use the following data set to answer questions 6-14: What is the probability that a person is satisfied given that they use system 9?

A marketing researcher at a computer company did a study examining user satisfaction with two operating systems.A total of 300 users were surveyed on the type of operating system used and their satisfaction with it.Use the following data set to answer questions 6-14: Given that it is impossible for a user to be satisfied and not satisfied with system 10 at the same time,these two events are called ___________________________.

A therapist claims that a particular technique has been successful in the treatment of eating disorders.You find out that only 7 out of 10 clients were actually helped.What is the probability of observing 7 successes if the probability of success = .5?

What is the difference between a permutation and a combination?

Determining what constitutes chance versus non-chance results under the assumption that the null hypothesis is true is done with reference to a probability value known as a(n):

Assuming the null hypothesis is false,we can easily specify an expected result.

What is a conditional probability?

Determining what constitutes chance versus non-chance findings under the assumption that the null hypothesis is true is made with reference to a probability value known as the alpha level.

For small n,the correction for _____ yields even better correspondence between the binomial and normal distributions.

Researchers in health and advertising are interested in looking at how alternative forms of alcohol advertising are related to actual alcohol use among youth.Imagine you have conducted a study looking at the relationship between owning an item that advertises alcohol (such as a hat,t-shirt or cup with an alcohol logo on it)and having tried alcohol among a group of 12-year-olds.You observe 500 cases total.Of those 500 cases,100 have tried alcohol.For the 100 cases who have tried alcohol,32 own an item that advertises alcohol.You wish to address the following research question: Is the observation that 32 out of 100 youths who have tried alcohol own an advertising item sufficient evidence to say that these two factors are related? Calculate the mean of the binomial distribution.Assume that p = .25.

According to the classical view of probability theory,the probability of event A equals .____.

There are no mathematical relationships among probabilities of simple events,conditional probabilities,and joint probabilities.

A biopsychologist is interested in how quickly rats learn a complicated maze.He puts 5 rats,labeled A,B,C,D,and E,in a box.He wants to run two of the rats through a maze,one rat at a time.How many subsets of 2 rats could he choose to run through the maze if order does NOT matter?

A conditional probability indicates the likelihood that an event will occur given that some other event occurs.

If our observations are so discrepant from the expected result that the difference cannot be attributed to chance,we will _____ the null hypothesis.

A researcher wanted to compare eye color distributions of babies born with a birth defect with babies who did not have the birth defect.26 babies with the defect were matched on gender,race,and age with 52 babies without the defect.The frequency of different eye colors as a function of the presence or absence of the defects was as follows: Eye Color Group Dark Medium Light Defect 1 6 19 No Defect 15 13 24 A ____ probability indicates the likelihood that an event will occur given that some other event occurs.