sample t-test

18,325 results

Statistics

Which test determines if there is a difference between the mean of a group and proposed standard value? Paired t-test F-test One Sample t-test One way ANOVA Two sample t-test

statistics

The College Board reported the following mean scores for the three parts of the Scholastic Aptitude Test (SAT) (The World Almanac, 2009): Assume that the population standard deviation on each part of the test is = 100. a. What is the probability a sample of 90 test takers will...

statistics

The College Board reported the following mean scores for the three parts of the Scholastic Aptitude Test (SAT) (The World Almanac, 2009): Assume that the population standard deviation on each part of the test is = 100. a. What is the probability a sample of 90 test takers will...

Statistics

The College Board reported the following mean scores for the three parts of the Scholastic Aptitude Test (SAT) (The World Almanac, 2009): Assume that the population standard deviation on each part of the test is = 100. a. What is the probability a sample of 90 test takers will...

Math

The College Board reported the following mean scores for the three parts of the Scholastic Aptitude Test (SAT) (The World Almanac, 2009): Assume that the population standard deviation on each part of the test is = 100. a. What is the probability a sample of 90 test takers will...

AP BIO

a student wished to test a sample of organic material to determine whether it was sugar, a dat, or starch. If she could perform only one of the following, which would be the most revealing? 1- test for the presence of carbon and hydrogen in the sample 2- test the sample to ...

statistics

7. A sample of 40 observations is selected from one population. The sample mean is 102 and the sample standard deviation is 5. A sample of 50 observations is selected from a second population. The sample mean is 99 and the sample standard deviation is 6. Conduct the following ...

Statistics

8. A sample of 65 observations is selected from one population. The sample mean is 2.67 and the sample standard deviation is .75. A sample of 50 observations is selected from a second population. The sample mean is 2.59 and the sample standard deviation is .66. Conduct the ...

statistics z or t test

the average weekly earnings of a production worker were \$424. to know if wages, on average, have gone up since that time. To test this, you sample 64 production workers, and determine that their average salary is \$432.69, with a sample standard deviation of \$33.90. Use a 0.05 ...

Statistics

The effectiveness of a headache medicine is tested by measuring the intensity of a headache in patients before and after drug treatment. The data consist of before and after intensities for each patient. Identify the design of the study. A) Paired t-test B) Two-sample t-test C...

Statistics

. A random sample is selected from a normal population with a mean of __40 and a standard deviation of __10. After a treatment is administered to the individuals in the sample, the sample mean is found to be M _ 42. a. How large a sample is necessary for this sample mean to be...

Probabilty & Statistic

A random sample is selected from a normal population with a mean of __40 and a standard deviation of __10. After a treatment is administered to the individuals in the sample, the sample mean is found to be M _ 42. a. How large a sample is necessary for this sample mean to be ...

statistics

A credit card company estimates that the average credit card balance of Americans is \$3,210. A statistics student wants to know whether this is true for citizens of her home town. Which hypothesis test would be most appropriate for addressing this question? One sample z-test ...

statistics

Select the TWO options that are TRUE statements about two-sample t-tests. Select one or more: The same formula is used for the ESE (estimated standard error) in the two-sample t-test with a common variance and the two-sample t-test with unequal variances. A researcher has ...

statistics

Select the TWO options that are TRUE statements about two-sample t-tests. Select one or more: The same formula is used for the ESE (estimated standard error) in the two-sample t-test with a common variance and the two-sample t-test with unequal variances. A researcher has ...

MATH STATS

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

Stats

Consider the following Hypotheses test: Ho:m>=80 Ha:m<80 A sample of 121 provided a sample mean of 77.3. The population Standard Deviation is known to be 16.5. A. compute the value of test statistic B. Determin the p value: and at 93.7% confidence, Test the above ...

t test

how to know exact t value using sample standard deviation and sample mean and sample size i think df is sample size -1 . we usually use approx value but to use exact value how to use t score table. and how we conclude whether it is two tailed test or one tailed test . (i f the...

statistics t test

how to know exact t value using sample standard deviation and sample mean and sample size i think df is sample size -1 . we usually use approx value but to use exact value how to use t score table. and how we conclude whether it is two tailed test or one tailed test . (i f the...

statistics

the average weekly earnings of a production worker were \$424. to know if wages, on average, have gone up since that time. To test this, you sample 64 production workers, and determine that their average salary is \$432.69, with a sample standard deviation of \$33.90. Use a 0.05 ...

statistics

1.test wheter these samples represent populations that are different from the general population- sample of 10 with a mean of 44 and sample of 1 with a mean of 48. 2. The general population of individuals has a mean of 40 , a deviation of 6, and follows a normal curve. for ...

STATS

Given a sample size of 18, with sample mean 660.3 and sample standard deviation 95.9 we are to perform the following hypothesis test. Null Hypothesis H0: ƒÊ = 700 Alternative Hypothesis H0: ƒÊ ‚ 700 At significance level 0.05 1. What is the critical value for this test...

Statistics

Which one of the following test is used to compare five means, simultaneously? Run test Normally test One way ANOVA 2 Sample T Test F-Test

psy/315

Two boats, the Prada (Italy) and the Oracle (USA), are competing for a spot in the upcoming America’s Cup race. They race over a part of the course several times. The sample times in minutes for the Prada were as follows: 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2...

statistics

You are conducting an experiment to see if a given therapy works to reduce test anxiety in a sample of college students. A standard measure of test anxiety is known to produce a  = 19. In the sample you draw of 86 the mean is equal 17.5 with standard deviation s = 10. a- Use ...

sssc

Suppose we test H0 : p = .3 versus Ha : p ≠ .3 and that a random sample of n = 100 gives a sample proportion p = .20. a: Test H0 versus Ha at the .01 level of significance by using critical values. What do you conclude? b: Find the p-value for this test. c: Use the p-...

Statistic

A restaurant that bills its house account monthly is concerned that the average monthly bill exceeds \$200 per account. A random sample of twelve accounts is selected, resulting in the sample mean of \$220 and a sample standard deviation of \$12. The researchers have determined ...

Statistic

A random sample has 61 values. The sample mean is 9.9 and the sample standard deviation is 2. Use a level of significance of a=0.01 to conduct a right-tailed test of the claim that the population mean is 9.2 ( i.e, H_0: u= 9.2, H_1: u>9.2). A)Compute the sample test ...

Economics 210

Information given is sample mean of 12 for a sample of 26. Sample deviation is 3. Using a .02 level of significance. H0 u< or equal to 10 and H1 u> 10 a. Is this a one or two tailed test? b. what is the decision rule? c. what is the value of the test statistic? d.what is...

Statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: A. a sample of 10 with a mean of 44. B.a sample of 1 with a mean of 48. The general population of ...

statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

Statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

psy325

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

Statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

Statistics

: For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

statistics

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

statistics

Given a sample size of 38, with sample mean 660.3 and sample standard deviation 95.9 we are to perform the following hypothesis test. Null Hypothesis H0: ƒÊ = 700 Alternative Hypothesis H0: ƒÊ ‚ 700 At significance level 0.05 3. Calculate the test statistics (Tip: this...

statistics

A researcher wants to carry out a hypothesis test involving the mean for a sample of n = 20. While the true value of the population standard deviation is unknown, the researcher is reasonably sure that the population is normally distributed. Given this information, which of ...

statistics

Assuming that the population variances are equal for Male and Female GPA’s, test the following sample data to see if Male and Female PhD candidate GPA’s (Means) are equal. Conduct a two-tail hypothesis test at á =.01 to determine whether the sample means are different. Do...

Statistics

The ____________ is a hypothesis-testing procedure in which there are two separate groups at people tested and the population variance is not known. - t test for dependent means - t test for a single sample - t test for independent means - t test for repeated measures

immediate help needed statistics one tailed hypo

the average weekly earnings of a production worker were \$424. to know if wages, on average, have gone up since that time. To test this, you sample 64 production workers, and determine that their average salary is \$432.69, with a sample standard deviation of \$33.90. Use a 0.05 ...

Help with Psychology Homework

Your professor asks you to take a personality test. After taking the test, you read your description of your personality type, and are disappointed that the results do not seem to capture your personality at all. In fact, you think the test probably measures attitudes rather ...

Biochemistry

1.How to test a sample with cholesterol? - Name of test? - Procedure of test? - Results

statistics

Suppose that the population standard deviation (ó) for a normally distributed standardized achievement test (ACT) is 6. What would the standard error of the sample mean (óxbar) be if we were to draw a random sample of 36 test scores?

STAT

Given a sample size of 18, with sample mean 660.3 and sample standard deviation 95.9, we are to perform the following hypothesis testing: Null Hypothesis H0 : µ = 700 Research Hypothesis H1 : µ ≠ 700 •What is the test statistics? •At a 0.05 significance level, what...

STAT

Given a sample size of 18, with sample mean 660.3 and sample standard deviation 95.9, we are to perform the following hypothesis testing: Null Hypothesis H0 : µ = 700 Research Hypothesis H1 : µ ≠ 700 •What is the test statistics? •At a 0.05 significance level, what...

Statistics

A sample of 64 observations is selected from a normal population. the sample mean is 215 and the standard deviation is 15. conduct the following test of hypothosis using the .3 significance level. Ho:u > or = 220 H1: u < 220 a) Is this a 1 tailed or 2 tailed test? b) ...

statistics

mortgage broker is offering home mortgages at a rate of 9.5%, but the broker is fearful that this value is higher than many others are charging. A sample of 40 mortgages filed in the county courthouse shows an average of 9.25% with a standard deviation of 8.61%. Does this ...

Science

In a one sample test, a sample is compared with a standard or benchmark. In a two sample test, the samples compared a. with two alternate hypotheses b. with an historical and a future benchmark c. with each other d. with opposing samples

statistics

Below are six data sets with 6 randomly selected scores in each data set. Your task is to determine if the scores were drawn from a population with μ = 5. Before you calculate the one-sample t test for each sample, make a guess as to whether or not you think the sample ...

Statistics

A sample of n = 25 scores has a mean of M = 40 and a variance of s2 = 100. If this sample is being used to test a null hypothesis stating that m = 43, then what is the t statistic for the sample

Psychology/Statistics

For each of the following samples that were given an experimental treatment test whether these samples represent populations that are different from the general population (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...

statistics

In performing a hypothesis test, the null hypothesis is population mean = 6.9 and the alternative hypothesis is population mean ≠ 6.9, a random sample of 16 items is selected. The sample mean is 7.1 and the sample standard deviation is 2.0. The population is approximated...

statistics

A researcher hypothesizes that individuals who listen to classical music will score differently from the general population on a test of spatial ability. On a standardized test of spatial ability, (u = 58). A random sample of 14 individuals who listen to classical music is ...

statistics

an auditor wishes to test the assumption that the mean value of all accounts receivable in a given firm is \$260.00 she will reject this claim only if it is clearly contradicted by the sample mean. the sample standard deviation of 36 accounts is \$43, the sample mean is \$250, ...

Math

The standard deviation of test scores on a certain achievement test Is 11.3. If a random sample of 81 students had a sample score of 74.6 , find a 90% confidence interval estimate for the average score of all students.

Statistics

Consider the hypothesis test given by Ho:u=530, H1:u does not equal 530. In a random sample of 85 subjects, the sample mean is found to be 522.3. Also, the population standard deviation is 29. Determine the P-value for this test. Is there sufficient evidence to justify the ...

Maths

A psychological test was given to 92 teenage boys and 68 teenage girls. The test was used to assign a score to each teenager, measured on the ‘worry scale’ – 0 (not worried) to 100 (very worried). A summary of the results is given in the table below. Girls; Sample Size ...

maths

What is mode n average for 2 students test scores our of 25 for maths. A Test 1: =21 Test 2: =24 Test 3:=19 Test 4: =21 K Test 1:= 18 Test 2:= 19 Test 3:= 19 Test 4:= 17 Test 2:= 19 Test 3:= 19 Test 4:= 17. N Test 1:= 16 Test 2:= 15 Test 3:=19..

Chem

A gas generator is constructed to collect the CO2(g) evolved from a reaction. during lab we set up the CO2 generator by placing 10ml of 3 M HCL in a 200mm test tube. then slide the 75mm test tube into the 200mm test tube without splashing any of the acid into the sample. The ...

statistics

Scores on a certain test are normally distributed with a variance of 14. A researcher wishes to estimate the mean score achieved by all adults on the test. Find the sample size needed to assure with 95% confidence that the sample mean will not differ from the population mean ...

business statistics

for a sample of 12 items from a normally distributed population for which the standard deviation is  = 17.0, the sample mean is 230.8. At the 0.05 level of significance, test Ho : μ ≤ 220 versus Hı: μ >220. Determine and interpret the p-value ...

Stats

A professor believes that all Thursday sections are cursed and will always score lower on tests compared to Monday sections. To tests this he collects samples of test scores from these two sections. For Monday's section, the mean test score was 60, the estimated population ...

Statistics

Two Boats the Picadilly and the Orange are competing for a spot in the Cup races. They race over a part of the course SEVERAL TIMES. The sample times in minutes for the Picadilly are 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2, and 11.3. The sample times for the ...

statistics

Scores on a certain test are normally distributed with a variance of 91. A researcher wishes to estimate the mean score achieved by all adults on the test. Find the sample size needed to assure with 95.44 percent confidence that the sample mean will not differ from the ...

statistics

In a recent study on gender differences in education, a sample of 7 boys had a mean score of 18.5 and a standard deviation of 4.1 on a Standardized Math Test. A sample of 11 girls had a mean score of 19.9 and a standard deviation of 3.6 on the same test. What is the t-...

statistics

Experience in investigating insurance claims shows that the average cost to process a claim is approximately normally distributed with a mean of \$80. New cost-cutting measures were started and a sample of 25 claims was tested. The sample mean of the costs to process these ...

statistics please

Experience in investigating insurance claims shows that the average cost to process a claim is approximately normally distributed with a mean of \$80. New cost-cutting measures were started and a sample of 25 claims was tested. The sample mean of the costs to process these ...

Stats

Recently, an automobile insurance company performed a study of a random sample of 15 of its customers to determine if there is a positive relationship between the number of miles driven and the age of the driver. The sample correlation coefficient is r=.38. Given this ...

statistics

3 In 1999, a sample of 200 in-store shoppers showed that 42 paid by debit card. In 2004, a sample of the same size showed that 62 paid by debit card. (a) Formulate appropriate hypotheses to test whether the percentage of debit card shoppers increased. (b) Carry out the test at...

Statistics

A study in Orlando, Florida claimed that the mean commute time for all employees working at Disney exceeds 40 minutes. This figure is higher than what was assumed in the past. The plan is to test this claim at a level of significance = 0.05 and a sample size = 100 commuters. ...

Statistics

This is the first question..... For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3. This is the second question....For each of the following samples that were given an experimental ...

statistics

Want to find if students who are musicians have higher Iq test scores than the general population. the researcher predicts that playing music is associated with higher IQ scores. the researcher selects a sample of 75 musicians from area and gives them an IQ test. The mean for ...

statistics

Given a sample size of 36, with sample mean 400 and sample standard deviation 85, we perform the following hypothesis test, at the 95% level of confidence: Ho: ƒÊ = 450, Ha: ƒÊ ‚ 450. What is the question and what is the answer?

Statistics

The interpretation of a test of significance can depend on the sample size and the practical context of the test. Write a short explanation of how sample size can affect the decision about statistical significance and whether or not the result is of any practical significance.

Statistics

Use a x squared-test to test the claim about the population variance or standard deviation at the given level of significance and using the given sample statistics. Claim: ơ2 ≤ 60; α = 0.025. Sample statistics: s2 = 72.7, n = 15

stats

A final exam in Math 160 has a mean of 73 with standard deviation 7.73. Assume that a random sample of 24 students is selected and the test score of the sample is computed. Assuming the scores are normally distributed, what percentage of sample means are less than 69?

Statistics

Use a chi-squared test to test the claim about the population variance or standard deviation at the given level of significance and using the given sample statistics. Claim: ơ2 ≤ 60; α = 0.025. Sample statistics: s2 = 72.7, n = 15

staistics

7) A final exam in Statistics has a mean of 73 with a standard deviation of 7.73. Assume that a random sample of 24 students is selected and the mean test score of the sample is computed. What percentage of sample means are less than 70?

Science

Suppose that you heated a sample of a hydrated ionic compound in a test tube. What might you expect to see inside the test tube, near the top of the test tube? Explain please i really am stumped on this question...

qnt/351

Which of the following statements about the two sample sizes is NOT true? Assume thepopulation standard deviations are equal A. Sample A = 11; sample B = 13 B. Sample A = 12; sample B = 14 C. Sample A = 13; sample B = 13 D. Sample A = 10; sample B = 16

statistics

Two-sample Non-parametric Test Now, we examine the relationship between cry time and group among infants at Northbay. 1. Suppose we wish to perform a two-sample test, but we do not want to make any normality (or other strong parametric) assumptions. Conduct an appropriate non-...

Statistics

In two-sample testing, when is it appropriate to use a t test or a z test

statistics

a random sample of 80 college students was selected to participate in a experiment. the mean of the sample is 317 points, the standard deviation of 37 there are 310 students that didn't complete the experiment 1. compute the appropriate test statistic? 2. what is the critical ...

statistics

For each of the following samples that were given an experimental treatment, test whether they represent populations that score significantly higher than the general population: (a) a smaple of 100 with a mean of 82, (b) a sample of 10 with a mean of 84. The general population...

statistics

Water sample from 6 public swimming pools are combined for one test regarding bacteria level.Further testing is done if the combined test fails. Past results have shown that there is a 2% chance of unacceptably high bacteria level. Determine the probability that the combined ...

Statistics

A researcher wished to test the effect of the addition of extra calcium to yogurt on the "tastiness" of yogurt. Two different yogurts, one with extra calcium and one without the added calcium, were created from the same batch of yogurt. A group of 84 adult volunteers ...

stats

Nicotine (mg) Filtered Kings Nonfiltered Kings n1 = 21 n2 = 8 sample mean = 0.94 sample mean = 1.65 s = 0.31 s = 0.16 Suppose you were to conduct a test (at the 0.05 significance level) to test the claim that king-size cigarettes with filters have a lower mean amount of ...

biochemistry

for each of these qualitative test,barfoed test,benedict test,seliwanoff test,bial test,molisch test,and iodine test, describe the class and give aspecific example of a carbohydrate that would yield a posiyive result?

Statistics

The mean of a population of raw scores is 33 1_X 5 122 . Use the criterion of .05 and the upper tail of the sampling distribution to test whether a sample with X 5 36.8 1N 5 302 represents this population. (a) What is the critical value? (b) Is the sample in the region of ...

Statistic

A random sample of size 20 drawn from a normal distribution has a sample mean of 8 and a sample standard deviation of 4. A) Compute the sample test statistic t under the null hypothesis H_0: Mue(mean)=7 B) State the alternate hypothesis if you believe that the population mean ...

Statistics Hypothsis testing

Am I using the 2-sample T test or ANOVA? Please show all steps. test the claim that μ1 = μ2 Two samples are randomly selected from normal populations. The sample statistics are n1=11,x(bar)=4.8, s1=.76 n2=18, x(bar)=5.2, s2=.51 Assume that σ1 ≠ σ2 - ...

statistics

A study in Orlando, Florida claimed that the mean commute time for all employees working at Disney exceeds 40 minutes. This figure is higher than what was assumed in the past. The plan is to test this claim at a level of significance = 0.05 and a sample size = 100 commuters. ...

Statistics

A study in Orlando, Florida claimed that the mean commute time for all employees working at Disney exceeds 40 minutes. This figure is higher than what was assumed in the past. The plan is to test this claim at a level of significance = 0.05 and a sample size = 100 commuters. ...

statistics

What is the purpose of a tukey test? Why can't we compare all the posible pairs of group means using the two-sample t-test?

statistics

. A random sample of 30 students obtained the following marks in a class test : (20) Test the hypothesis that their median score is more than 50. 58 55 25 32 26 85 44 80 33 72 10 42 15 46 64 39 38 30 36 65 72 46 54 36 89 94 25 74 66 29