QMB 3250 EXAM QUESTIONS WITH 100%
CORRECT SOLUTIONS!!
What is a response variable?
what the study is trying to determine
To look at the relationship between Serum 25(OD)D levels and location(urban/rural), what
type of graph might you use?
boxplot
A histogram is a graphical display to show _________ .
the outcomes of a quantitative variable.
What is the primary purpose of the 95% confidence interval for μ2-μ1 ?
To estimate the difference between the mean of population 1 and population 2. The Confidence
Interval for two independent means is interested in estimating the difference between the
parameters.
In significance testing, what does α represent?
The probability of a Type I error
what type of statistical test should be used to determine are older people more likely than
younger people to consider purchasing a hybrid vehicle?
Comparing two independent proportions
categorical data - two groups
,what type of statistical test should be used to determine what is the typical price of a used
Toyota Prius manufactured in 2011?
One Mean
quantitative data - one group
what type of statistical test should be used to determine if there is a difference in used car
price for a Toyota Prius with 2 or 4 cylinders?
Comparing two independent means
quantitative data - two groups
what type of statistical test should be used to determine if there is a significant difference in
gas mileage for a Toyota Prius driven 100 miles in the mountains versus along a flat
coastline? Ten drivers determine their gas mileage for the same stretch of roads in the
mountains and along the flat coastline.
Comparing means of dependent samples
quantitative data - paired responses
what type of statistical test should be used to determine what proportion of people
purchase a hybrid cars after they have been given a test drive?
One Proportion
categorical data - one group
In the past the average life span for a flashlight battery has been 10 hours. However, the
production line has been improved in the past six months. The manufacturer wants to
, determine if the lifetime of the battery has improved. The manufacturer tested the lifetimes
of 25 batteries. What would be the appropriate hypothesis to test this claim?
Ho: μ =10 versus Ha: μ >10
In the past the average life span for a flashlight battery has been 10 hours. However, the
production line has been improved in the past six months. The manufacturer wants to
determine if the lifetime of the battery has improved. The manufacturer tested the lifetimes
of 25 batteries. What is the parameter being estimated?
μ = population mean lifetime of the battery
For the hypothesis Ho: μ1-μ2=0 versus Ha: μ1-μ2≠0, the p-value equals 0.021. Let α = 0.05.
What decision would be made here? If an error is made here, what type of error would it
be?
Reject Ho
Rule: p-value ≤ α Reject Ho The p-value = 0.021 < α = 0.05
Type I error since we rejected Ho, the only type of error that we could make if we made an error
would be Type I error. The definition of a type 1 error is the error that occurs when we reject Ho
when Ho is true.
type 1 error
is the error that occurs when we reject Ho when Ho is true
For a significance test for the population proportion with significance level equal to 0.10
and p-value equal to 0.06, what would be the correct decision?
CORRECT SOLUTIONS!!
What is a response variable?
what the study is trying to determine
To look at the relationship between Serum 25(OD)D levels and location(urban/rural), what
type of graph might you use?
boxplot
A histogram is a graphical display to show _________ .
the outcomes of a quantitative variable.
What is the primary purpose of the 95% confidence interval for μ2-μ1 ?
To estimate the difference between the mean of population 1 and population 2. The Confidence
Interval for two independent means is interested in estimating the difference between the
parameters.
In significance testing, what does α represent?
The probability of a Type I error
what type of statistical test should be used to determine are older people more likely than
younger people to consider purchasing a hybrid vehicle?
Comparing two independent proportions
categorical data - two groups
,what type of statistical test should be used to determine what is the typical price of a used
Toyota Prius manufactured in 2011?
One Mean
quantitative data - one group
what type of statistical test should be used to determine if there is a difference in used car
price for a Toyota Prius with 2 or 4 cylinders?
Comparing two independent means
quantitative data - two groups
what type of statistical test should be used to determine if there is a significant difference in
gas mileage for a Toyota Prius driven 100 miles in the mountains versus along a flat
coastline? Ten drivers determine their gas mileage for the same stretch of roads in the
mountains and along the flat coastline.
Comparing means of dependent samples
quantitative data - paired responses
what type of statistical test should be used to determine what proportion of people
purchase a hybrid cars after they have been given a test drive?
One Proportion
categorical data - one group
In the past the average life span for a flashlight battery has been 10 hours. However, the
production line has been improved in the past six months. The manufacturer wants to
, determine if the lifetime of the battery has improved. The manufacturer tested the lifetimes
of 25 batteries. What would be the appropriate hypothesis to test this claim?
Ho: μ =10 versus Ha: μ >10
In the past the average life span for a flashlight battery has been 10 hours. However, the
production line has been improved in the past six months. The manufacturer wants to
determine if the lifetime of the battery has improved. The manufacturer tested the lifetimes
of 25 batteries. What is the parameter being estimated?
μ = population mean lifetime of the battery
For the hypothesis Ho: μ1-μ2=0 versus Ha: μ1-μ2≠0, the p-value equals 0.021. Let α = 0.05.
What decision would be made here? If an error is made here, what type of error would it
be?
Reject Ho
Rule: p-value ≤ α Reject Ho The p-value = 0.021 < α = 0.05
Type I error since we rejected Ho, the only type of error that we could make if we made an error
would be Type I error. The definition of a type 1 error is the error that occurs when we reject Ho
when Ho is true.
type 1 error
is the error that occurs when we reject Ho when Ho is true
For a significance test for the population proportion with significance level equal to 0.10
and p-value equal to 0.06, what would be the correct decision?
