BUAL 2650 Final Exam UPDATED Study
ACTUAL QUESTIONS AND CORRECT
ANSWERS
Alpha (a) - CORRECT ANSWER -level of significance
-allowance for a Type I error
-evidence is found significant we reject the null
Hypothesis testing of proportions uses what tables? - CORRECT ANSWER z tables
P-value - CORRECT ANSWER -the probability of the null being true
-observed level of significance
1-test statistic from table
P-value < a - CORRECT ANSWER reject the null
Test statistic > CV - CORRECT ANSWER we reject the null
Two-Tailed p-value - CORRECT ANSWER the p-value of a two tailed test is both shaded
areas added together
An example in the judicial system - CORRECT ANSWER the null is that the defendant is "not
guilty"
Type I Error - CORRECT ANSWER -made in rejecting a null when it is actually true
-false positive
Type II Error - CORRECT ANSWER -failing to reject the null when in fact it is false
, -false negative
Power of a Test - CORRECT ANSWER -the ability of the test to make the correct decision of
rejecting the null when it is false
-making the right decision
-1-P(Type II) aka 1-Beta
-want it to be high
-as a increases, B decreases
Central Limit Theorem - CORRECT ANSWER sampling distribution of any mean becomes
normal as the sample size grows
Hypothesis testing of means uses what tables? - CORRECT ANSWER -t tables
-as degrees of freedom increase, t-models look more normal
How do we reduce both Type I & II errors? - CORRECT ANSWER we increase the sample
size
Paired Data - CORRECT ANSWER occurs as "before and after"
What are the 3 properties of sample distribution and sample mean? - CORRECT ANSWER -
the mean of the sample means is equal to the population mean
-the standard deviation of the sample means is equal to the population standard deviation, divided by
the square root of n
-the standard error of the mean is the standard deviation of the sample means
Goodness of fit test - CORRECT ANSWER -determines if observed proportions conform to
expected ones
-levels of classification (k)
-df = k - 1
Chi Square (x^2) - CORRECT ANSWER -the distribution used to test goodness of fit
ACTUAL QUESTIONS AND CORRECT
ANSWERS
Alpha (a) - CORRECT ANSWER -level of significance
-allowance for a Type I error
-evidence is found significant we reject the null
Hypothesis testing of proportions uses what tables? - CORRECT ANSWER z tables
P-value - CORRECT ANSWER -the probability of the null being true
-observed level of significance
1-test statistic from table
P-value < a - CORRECT ANSWER reject the null
Test statistic > CV - CORRECT ANSWER we reject the null
Two-Tailed p-value - CORRECT ANSWER the p-value of a two tailed test is both shaded
areas added together
An example in the judicial system - CORRECT ANSWER the null is that the defendant is "not
guilty"
Type I Error - CORRECT ANSWER -made in rejecting a null when it is actually true
-false positive
Type II Error - CORRECT ANSWER -failing to reject the null when in fact it is false
, -false negative
Power of a Test - CORRECT ANSWER -the ability of the test to make the correct decision of
rejecting the null when it is false
-making the right decision
-1-P(Type II) aka 1-Beta
-want it to be high
-as a increases, B decreases
Central Limit Theorem - CORRECT ANSWER sampling distribution of any mean becomes
normal as the sample size grows
Hypothesis testing of means uses what tables? - CORRECT ANSWER -t tables
-as degrees of freedom increase, t-models look more normal
How do we reduce both Type I & II errors? - CORRECT ANSWER we increase the sample
size
Paired Data - CORRECT ANSWER occurs as "before and after"
What are the 3 properties of sample distribution and sample mean? - CORRECT ANSWER -
the mean of the sample means is equal to the population mean
-the standard deviation of the sample means is equal to the population standard deviation, divided by
the square root of n
-the standard error of the mean is the standard deviation of the sample means
Goodness of fit test - CORRECT ANSWER -determines if observed proportions conform to
expected ones
-levels of classification (k)
-df = k - 1
Chi Square (x^2) - CORRECT ANSWER -the distribution used to test goodness of fit
