Math Homework

Ask Math Questions. Get Help With Your Math Homework

Ask an Expert,
Get an Answer ASAP!

1) If a hypothesis test has a level of significance of 5%,

Customer Question
that means if the null...
1) If a hypothesis test has a level of significance of 5%, that means if the null is true, we don’t reject it 5% of the time.
A. True
B. False



2) “µ = 17” is an appropriate null hypothesis.
A. True
B. False



3) The value that separates a rejection region from a non-rejection region is called the test statistic.
A. True
B. False



4) We have created a 95% confidence interval for µ with the result [10, 15]. What conclusion will we make if we test H0: µ = 16 versus H1: µ ? 16 at a = 0.05?
A. Accept the null.
B. Reject the null and conclude the alternative.
C. We cannot tell what our decisions will be from the information.
D. Fail to reject the null.



5) The Roman Senate has become concerned about the loyalty of the army in Gaul commanded by Julius Caesar. They claim that, of the 80,000 men in the army, at least 28,000 are foreign barbarians. Caesar believes there are fewer barbarians, so the Senate should not worry. He polls one legion of 1,000 men and finds that 340 of them are barbarians. What is the test statistic for this hypothesis test?
A. (0.35-0.34)/100
B. (0.35-0.34)/0.2275
C. (0.34-0.35)/0.063
D. (0.34-0.35)/0.015



6) You performed a right-tailed hypothesis test and your sample gave you a test statistic in the left tail. Which of the following is considered the appropriate next step in this test?
A. Fail to reject the null.
B. Change the level of significance of your test.
C. Change the sample and do the test again.
D. Change the direction of the hypothesis.



7) A test for equality of two variances has samples sizes n1 = 13 and n2 = 10. The degrees of freedom for the test are
A. 21.
B. 26.
C. 12 and 9.
D. 13 and 10.



8) A test for equality of two variances is based on
A. A. the difference between the sample variances.
B. the difference between the population variances.
C. the ratio of the sample variances
D. C. the difference between the sample coefficients of variation.



9) If the paired differences are normal in a test of mean differences, then the distribution used for testing is the
A. normal distribution
B. Chi-Square
C. F distribution
D. Student t distribution



10) Testing the difference of means of independent samples must always be a two-tailed test.
A. True
B. False



11) In a test for the equality of two variances (two-tailed), when the populations are normal, a 5% level of significance was used. Sample sizes were n1 = 13 and n2 = 10. The upper critical value for the test is
A. =FINV(0.05, 12, 9).
B. =FINV(0.025, 12, 9).
C. =FINV(1-0.025, 13, 10).
D. =FINV(0.025, 13, 10).



12) 100 women were polled and 60 reported successfully communicating an automobile problem to an auto repairman. A sample of 150 men had 95 reporting the same success. The value of the test statistic for a test of the equality of proportions is
A. -0.5319.
B. 0.7293.
C. 0.2702.
D. -0.419.

13) The expected value of the sampling distribution of the sample mean equals the populations mean
A. When the population is normally distributed.
B. When the population is symmetric.
C. When the population size N>30.
D. For all populations.



14) Which of the following statements is consistent with the Central Limit Theorem?
A. When µ and s are known, the population will be approximately normally distributed.
B. If a population has µ and s, a sample from that population will be normally distributed if the sample size is large enough.
C. When we know s, the variation in the sample means will be equal to that of the population.
D. Means of samples of n=30 from an exponential distribution will be approximately normally distributed.



15) A random variable follows the Student’s t distribution. The probability that it will be positive is
A. 1
B. .50
C. Less than 0.50
D. 0



16) A test for equality of two variances is based on
A. the difference between the sample variances.
B. the difference between the population variances.
C. the difference between the sample coefficients of variation.
D. the ratio of the sample variances.



17) If the paired differences are normal in a test of mean differences, the distribution used for testing is the
A. normal distribution.
B. chi-square.
C. student t distribution.
D. f distribution.



18) A pooled proportion estimate may be used to calculate the test statistic for a test of the equality of proportions when the
A. populations are normally distributed.
B. sample sizes are small.
C. samples are independently drawn from the populations.
D. null hypothesis states that the two population proportions are equal.



19) An analysis of variance (ANOVA) tests population variance.
A. True
B. False



20) The purpose of designing a randomized block experiment is to reduce the between-treatments variation (SST) to more easily detect differences between the treatment means.
A. True
B. False



21) The F-test of the randomized block design of the analysis of variance has the same requirements as the independent sample design; that is, the random variable must be normally distributed and the population variances must be equal.
A. True
B. False



22) Which of the following is not required to perform a one-factor ANOVA?
A. The sample sizes must be equal.
B. The samples for each treatment must be selected randomly and independently.
C. The populations must be normally distributed.
D. The population variances must be equal.



23) Hartley's test measures the equality of the means for several groups.
A. True
B. False



24) Which of the following statistics from the ANOVA table do not have an additive relationship?
A. Sum of squares
B. It is not possible to tell.
C. Degrees of freedom
D. Mean squares

25) The nonparametric counterpart of the parametric one-way analysis of variance F-test is the
A. Kruskal-Wallis test.
B. Wilcoxon signed rank sum test.
C. Friedman test.
D. Spearman’s rho.



26) The appropriate measure of central location of ordinal data is the
A. mean.
B. median.
C. mode.
D. all of these.



27) Statistical methods that require few assumptions, if any, about the population distribution are known as
A. nonparametric techniques.
B. All of these
C. parametric techniques.
D. free agent techniques.



28) In the chi-squared goodness-of-fit test, if the expected frequencies ei and the observed frequencies fi were quite different, we would conclude that the
A. null hypothesis is false, and we would reject it.
B. chi-squared distribution is invalid, and we would use the t-distribution. instead
C. null hypothesis is true, and we would not reject it.
D. alternative hypothesis is false, and we would reject it.



29) If each observation can be classified into one of several mutually exclusive and collectively exhaustive categories, the population is a
A. normal
B. chi-squared.
C. binomial.
D. multinomial.



30) The number of degrees of freedom in testing for normality is the
A. number of intervals used to test the hypothesis minus 1.
B. number of intervals used to test the hypothesis minus number of parameters estimated minus 1.
C. number of intervals used to test the hypothesis minus number of parameters estimated minus 2.
D. number of parameters estimated minus 1.



31) The Kruskal-Wallis test statistic may be approximated by a chi-squared distribution with c-1 degrees of freedom, where c is the number of populations, whenever the sample sizes are all greater than or equal to
A. 5
B. 25
C. 30
D. 15



32) For applications of the Kruskal-Wallis test, the alternative hypothesis to be tested is:
A. All c population medians are the same.
B. At least two population medians are the same.
C. At least two population medians are different.
D. All c population medians are different.



33) How many runs are in the sequence TFTFFFFTTF?
A. 2
B. 5
C. 6
D. 4

34) A regression analysis between sales, in $1,000, and advertising, in $100, resulted in the following least squares line: Sales' = 75 + 6*(Advertising). This implies that if advertising is $800, sales will be
A. $4,875.
B. $12,300.
C. $123,000.
D. $487,500.



35) In regression analysis, if the coefficient of determination is 1.0, then the coefficient of correlation must be 1.0.
A. True
B. False



36) The value of the sum of squares for regression SSR can never be larger than the value of total sum of squares SST.
A. True
B. False



37) What randomness exists in the linear regression model?
A. The randomness from the explanatory variables, the X's
B. The randomness from what is unexplained, the error
C. The randomness of the dependent variable, the Y's
D. None of these



38) When a dummy variable is included in a multiple regression model, the interpretation of the estimated slope coefficient does not make any sense.
A. True
B. False



39) When using the least squares method, the column of residuals always sums to zero.
A. True
B. False



40) If the coefficient of correlation is –0.81, then the percentage of the variation in y that is explained by the regression line is 81%.
A. True
B. False



41) Given that SSE = 84 and SSR = 358.12, the coefficient of correlation, also called the Pearson coefficient of correlation, must be 0.90.
A. True
B. False



42) The regression line y = 2 + 3x has been fitted to the data points (4,11), (2,7), and (1,5). The sum of squares for error will be 10.0
A. True
B. False



43) Interpret the coefficient on gender.
A. Ceteris paribus: a male is paid $9,290 less on average than a female.
B. Ceteris paribus: a female is paid $9,290 less on average than a male.
C. Ceteris paribus: if a woman changes her gender, she will receive $9,290 less.
D. Ceteris paribus: for each additional dollar of salary, a female’s salary moves 9.29 units closer to a male’s salary.



44) If the Durbin-Watson statistic has a value close to 0, which assumption is violated?
A. Independence of errors
B. Normality of the errors
C. Homoscedasticity
D. None of these



45) If the Durbin-Watson statistic, DW, has values greater than 2, this indicates
A. a positive first–order autocorrelation.
B. a negative first–order autocorrelation.
C. no first–order autocorrelation at all.
D. None of the above

46) For which of the following values of the smoothing constant a will the smoothed series catch up most quickly whenever the original time series changes direction?
A. 0.90
B. 0.50
C. 0.40
D. 0.10



47) If we want to measure the seasonal variations on stock market performance by quarter, we would need
A. 4 indicator variables.
B. 3 indicator variables.
C. 2 indicator variables.
D. 1 indicator variables.



48) The time series component that reflects variability over short, repetitive time periods that last less than one year is called
A. long–term trend.
B. cyclical variation.
C. seasonal variation.
D. irregular variation.



49) When the only sources of variation in a production process are caused by chance, the process is said to be
A. out of balance but under control.
B. out of control but in balance.
C. under control.
D. out of control.



50) Variations in process output that are caused by a number of randomly occurring events that are part of the production process are
A. special causes.
B. common causes.
C. out-of-control causes.
D. All of the these



51) In statistical process control, a Type I error occurs if we decide that the process is
A. under control when it is out of control.
B. out of control when it is under control.
C. under control when it is under control.
D. out of control when it is out of control.
Submitted: 8 years ago.Category: Math Homework
Show More
Show Less
Ask Your Own Math Homework Question
Answered in 15 hours by:
6/28/2010
Math Tutor or Teacher: rajeevanpillai, Master's Degree replied 8 years ago
rajeevanpillai
rajeevanpillai, Master's Degree
Category: Math Homework
Satisfied Customers: 741
Experience: M.Sc Statistics MPhil Statistics
Verified
Click here and here

Click ACCEPT if I have helped you.
Bonus and Positive feedback are appreciated.

Edited by Rajeevan Pillai on 6/29/2010 at 2:07 PM EST
Ask Your Own Math Homework Question
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a math tutor or teacherLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask rajeevanpillai Your Own Question
rajeevanpillai
rajeevanpillai
rajeevanpillai, Master's Degree
Category: Math Homework
Satisfied Customers: 741
741 Satisfied Customers
Experience: M.Sc Statistics MPhil Statistics

rajeevanpillai is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Mr. Gregory White

Mr. Gregory White

Master's Degree

92 satisfied customers

M.A., M.S. Education / Educational Administration

JACUSTOMER-yrynbdjl-

JACUSTOMER-yrynbdjl-

Master's Degree

49 satisfied customers

I have taught college Mathematics for the past 10 years.

SusanAthena

SusanAthena

Master's Degree

41 satisfied customers

Tutor for Algebra, Geometry, Statistics. Explaining math in plain English.

Dr Arthur Rubin

Dr Arthur Rubin

Doctoral Degree

38 satisfied customers

Ph.D. in Mathematics, California Institute of Technology

mhasan420

mhasan420

Master's Degree

29 satisfied customers

BA Maths, Oxford

Don

Don

Master's Degree

17 satisfied customers

M.S. Astronautical Engineering. Math/Science/Comp Tutor

judybailey61

judybailey61

Bachelor's Degree

17 satisfied customers

20 years teaching mathematics

< Previous | Next >

Related Math Homework Questions
Type II error is committed when we reject a null hypothesis
Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) The v… read more
rajeevanpillai
rajeevanpillai
Master's Degree
Master's Degree
741 satisfied customers
Section 1 1) 17” is an appropriate null hypothesis.
Section 1 1) “µ = 17” is an appropriate null hypothesis. A. True B. False 2) The value that separates a rejection region from a non-rejection region is called the test statistic. A. True B. False 3) I… read more
Tom
Tom
Business Analyst
Master\u0027s Degree
316 satisfied customers
Section 1 1) 17” is an appropriate null hypothesis. A.
Section 1 1) “µ = 17” is an appropriate null hypothesis. A. True B. False 2) The value that separates a rejection region from a non-rejection region is called the test statistic. A. True B. False 3) I… read more
R.R. Jha
R.R. Jha
Bachelor\u0027s Degree
150 satisfied customers
1) A Type II error is committed when we reject a null hypothesis
1) A Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) … read more
rajeevanpillai
rajeevanpillai
Master's Degree
Master's Degree
741 satisfied customers
1) If a sociologist wishes to determine if there is evidence
1) If a sociologist wishes to determine if there is evidence that average family in a community exceeds $47,000, a two-tailed test should be used. A. True B. False 2) A Type II error is committed when… read more
Scott
Scott
MIT Graduate
Master\u0027s Degree
213 satisfied customers
25) Statistical methods that require few assumptions, if any,
25) Statistical methods that require few assumptions, if any, about the population distribution are known as A. nonparametric techniques. B. All of these C. parametric techniques. D. free agent techni… read more
Scott
Scott
MIT Graduate
Master\u0027s Degree
213 satisfied customers
9) A test for equality of two variances is based on A.
9) A test for equality of two variances is based on A. the ratio of the sample variances B. the difference between the population variances. C. C. the difference between the sample coefficients of var… read more
rajeevanpillai
rajeevanpillai
Master's Degree
Master's Degree
741 satisfied customers
1) If a hypothesis test has a level of significance of 5%,
1) If a hypothesis test has a level of significance of 5%, that means if the null is true, we don't reject it 5% of the time. A. True B. False 2) “µ = 17” is an appropriate null hypothesis. A. True B.… read more
rajeevanpillai
rajeevanpillai
Master's Degree
Master's Degree
741 satisfied customers
A Type II error is committed when we reject a null hypothesis
A Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) The… read more
StatisticsExpert
StatisticsExpert
Asst. Professor
Doctoral Degree
5 satisfied customers
A Type II error is committed when we reject a null hypothesis
A Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) The… read more
StatisticsExpert
StatisticsExpert
Asst. Professor
Doctoral Degree
5 satisfied customers
1) A Type II error is committed when we reject a null hypothesis
1) A Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) “µ = 17” is an appropriate null hypothesis. A. True B. False 3) The value that separates a rejection … read more
OnlineTutor
OnlineTutor
Research Scholar
Master\u0027s Degree
86 satisfied customers
A Type II error is committed when we reject a null hypothesis
A Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) The… read more
OnlineTutor
OnlineTutor
Research Scholar
Master\u0027s Degree
86 satisfied customers
A Type II error is committed when we reject a null hypothesis
A Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) The… read more
rajeevanpillai
rajeevanpillai
Master's Degree
Master's Degree
741 satisfied customers
A Type II error is committed when we reject a null hypothesis
A Type II error is committed when we reject a null hypothesis that is true. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) The… read more
StatisticsExpert
StatisticsExpert
Asst. Professor
Doctoral Degree
5 satisfied customers
14) A pooled proportion estimate may be used to calculate
14) A pooled proportion estimate may be used to calculate the test statistic for a test of the equality of proportions when the A. sample sizes are small. B. samples are independently drawn from the p… read more
Sandhya_sharma
Sandhya_sharma
Master\u0027s Degree
560 satisfied customers
10) A random variable follows the Students t distribution.
10) A random variable follows the Student's t distribution. The probability that it will be positive is A. Less than 0.50 B. .05 C. 1 D. 0 11) Which of the following statements is consistent with the … read more
OnlineTutor
OnlineTutor
Research Scholar
Master\u0027s Degree
86 satisfied customers
10) For a sample size of 1, the sampling distribution of the
10) For a sample size of 1, the sampling distribution of the mean will be normally distributed A. Only if the population values are larger than 30. B. Only if the population is normally distributed. C… read more
rajeevanpillai
rajeevanpillai
Master's Degree
Master's Degree
741 satisfied customers
Need the answers in 25 min need to review before test
10) A random variable follows the Student's t distribution. The probability that it will be positive is A. Less than 0.50 B. .05 C. 1 D. 0 11) Which of the following statements is consistent with the … read more
OnlineTutor
OnlineTutor
Research Scholar
Master\u0027s Degree
86 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x