Exam 6: Probability

A sample of 500 people aged 30 - 40 years old were interviewed to study the relationship between whether a person graduated from college or only high school and whether s/he changed jobs in the last 5 years.The results are found in the contingency table below. Answers below have been rounded to two decimal places. What is the probability that an individual has changed jobs,given that they have graduated from high school only?

Probability theory is important to understand because

A permutation of a set of objects or events is a sequence in which the internal ordering of elements is irrelevant.

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 10?

An experiment is conducted with 200 trials and the probability of a success in each trial is .250.What is the mean of the binomial distribution?

If the size of a sample is approximately 5% or less of the population,sampling with versus without replacement will have a large affect on probabilities calculated.

A sample of 500 people aged 30 - 40 years old were interviewed to study the relationship between whether a person graduated from college or only high school and whether s/he changed jobs in the last 5 years.The results are found in the contingency table below. Answers below have been rounded to two decimal places. What is the probability that an individual has not changed jobs,given that they have graduated from high school only?

In a binomial probability calculation,there are ____ possible outcomes.

What is a joint probability?

A(n)_____ of a set of objects or events is an ordered sequence.

In hypothesis testing,if observations are very similar to what would be expected from chance alone,we ____________________the null hypothesis.

When the alpha level is .05,a result is defined as non-chance if the probability of obtaining that result,assuming the null hypothesis is true,is greater than .05.

The correspondence between the binomial and normal distributions improves as n increases and as p becomes closer to .50.

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?

Sampling without replacement involves selecting a case at random and then,without replacing this case,selecting another case at random.

If one was testing the effectiveness of a therapy technique,the alternative hypothesis states that there is NO change due to the technique.

The statement "Given that a person is satisfied with his job,what is the probability that he is satisfied with his marriage?" is an example of a(n):

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.

What does it mean to say that two outcomes are mutually exclusive?

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.