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Hypothesis Testing

Correlation coefficient & 7-step hypothesis test

In order for applicants to work for the state department, they must take a test in the language of the country where they plan to work. The data below shows the relationship between the number of years that applicants have studied a particular language and the grades they received on the proficiency exam. Applicant # 1 2 3 4


1) Formulate both a numerical and verbal hypothesis statement regarding your research issue. 2) Perform the five-step hypothesis test on data pertaining to your selection.

Two questions: variances

1] For the samples summarized below, test the hypothesis at = 0.5 that the two variances are equal. Sample 1 Variance = 25 Number of data values = 9 Sample 2 Variance = 9 Number of data values = 19 Do we reject or not reject and why 2] A marketing firm asked a random set of mar

Hypothesis Testing and Distributions

Evolutionary theories often emphasize that humans have adapted to their physical environment. One such theory hypothesizes that people should spontaneously follow a 24-hour cycle of sleeping and waking?even if they are not exposed to the usual pattern of sunlight. To test this notion, eight paid volunteers were placed (individua

Significance Level for Interest Rates

In recent years, the interest rate on home mortgages has declined to less than 6.0 percent. However, according to a study by the Federal Reserve Board, the rate charges on credit card debt is more than 14 percent. Listed below is the interest rate charged on a sample of 10 credit cards. 14.6 16.7 17.4 17.0 17.8 15.4 13.1 15.8

ANOVA;analysis of variance, etc

1. To determine if a diet supplement is useful for increasing weight, patients are weighed at the start of the program and at the end of the program. This is an example of a. test of paired differences. b. independent sample. c. one-sample test for means. d. two-sample test for means. 2. The analysis of variance tech

Just need a mapping

I downloaded all of the problems separately and just need a mapping into the instructors grading key, Can someone please help with this? I think there is one problem without a solution. And I really need the formulas spelled out so I can replicate them. Thanks

Comparison Distribution for Sample Scores

Based on the information given for each of the following studies, decide whether to reject the null hypothesis. For each, give the Z-score cutoff (or cutoffs) on the comparison distribution at which the null hypothesis should be rejected, the Z score on the comparison distribution for the sample score, and your conclusion. Assum

Regional Differences in Household Savings

For items 1 to 4, select the best statistical analysis technique for the following research topics. Be very precise about your statistical choice. For example, there are several types of t-tests, correlations, and ANOVA tests. Make sure you specify exactly which statistical analysis technique you would use, e.g. One-Way Anova

Z tests & t tests

1. If two independent samples are used in a hypothesis test concerning the difference between population means for which the combined degrees of freedom is 20, which of the following could not be true about the sample sizes n1 and n2? A) n1=12 and n2=8 B) n1=12 and n2=10 C) n1=13 and n2=9 D) Cannot be determined from the giv

Significant Linear Relationship

The city of Denver wishes to see if there is a linear relationship between temperature and the amount of electricity used (in kilowatts) Based on the data below, is there a significant linear relationship between temperature and the amount of electricity used? Temperature (x) 73 78 85 98 93 81 76 105

Proportion of Germinating Seeds Testing

The data presented in the table below resulted from an experiment in which seeds of 5 different types were planted and the number of seeds that germinated within 5 weeks after planting was recorded for each seed type. At the .01 level of significance, is the proportion of seeds that germinate dependent on the seed type?

Hypothesis Testing - Battery Life

A manufacturer of flashlight batteries took a sample of 13 batteries from a day's production and used them continuously until they failed to work. The life lengths of the batteries, in hours, until they failed were: 342, 426, 317, 545, 264, 451, 1049, 631, 512, 266, 492, 562, and 298. At the .05 level of significance, is ther

Hypothesis Testing for Environmental Estimates

An environmentalist estimates that the more waste recycled by adults in the country is more than 1 pound per person per day. You want to test this claim. You find that the mean waste recycled per person per day for a random sample of 9 adults in the country is 2 pounds and the standard deviation is 0.3 pound. At a = 0.10, can

Hypothesis Testing for a Chess Club Claims

A local chess club claims that the length of time to play a game has a mean of 49 minutes or more. Write sentences describing type I and type II errors for a hypothesis test o this claim. A Type I error will occur if the actual mean of the length of time to play a game is "pick one to insert in sentence" (less than, equal t

Identifying Null and Alternative Hypotheses

Write the null and alternative hypotheses. Identify which is the claim. A light bulb manufacturer claims that the mean life of a certain type of light bulb is less than 775 hours. a) Write the claim mathematically and identify Ho and Ha? b) Identify which is the claim? (choose one) The null hypothesis Ho is the

Level of Significance for Patient Risk

Considering that a researcher can test at the <p = .05 (95%), p = .01 (99%), or p = .001 (99.9%) level for statistical significance, how would you use these three levels in relationship to risk to patients in implementing the decisions of your research?

Statistics - Evidence to reject Hypothesis or not

A random group of students was selected from a large student conference to analyze their class in school. Is there evidence to reject the hypothesis that the number of students is equally distributed between the four classes, at alpha = .05? Give the test value? Freshman = 9 Sophomores = 9 Juniors = 10 Seniors = 21

Critical value and dfD and dfN

Question # 1 The critical value for this problem should have dfN and dfD of what? ANOVA TABLE Source Sum of Squares Degrees of Freedom Between 22 2 Within(error) 39 34 Total 61

Hypothesis Testing of Mean P-Value Method

Task: Use a P-value to test the claim about the population mean using the given sample statistics. State your decision for a=0.05. Claim: mean does not = 230; Sample statistics: x(bar) = 216.5, s=17.3, n=48.

Solutions for Hypothesis Testing

1. In Meijer supermarket, the customer's waiting time to check out is approximately normally distributed with a standard deviation of 2.5 minutes. A sample of 25 customer waiting times produced a mean of 8.2 minutes. Is this evidence sufficient to reject the supermarket's claim that its customer checkout time averages no more th

Hypothesis Testing Approach Methods

Hypothesis Testing for Proportions. 4. A flash drive manufacturer has set a standard on their production process. When defects exceed 3%, the production process is unacceptable. A random sample of 85 drives is tested. The defective rate is 5.9%. Use a level of significance of  = 0.01 to test to see if you have sufficient e

Hypothesis Testing for Mean-Local Tire Store

Hypothesis Testing for Mean (Small Samples) 1. A local tire store suspects that the mean life of a new discount tire is less that 39,000 miles. To check the claim, the store selects randomly 18 of these new discount tires. When they are tested, it is found that the mean life is 38,250 miles with a sample standard deviation s

Hypothesis Testing for the Mean (Large Samples)

Hypothesis Testing for the Mean (Large Samples) 1. Use the method specified to perform the hypothesis test for the population mean . WeatherBug say that the mean daily high for December in a large Florida cit is F. WFLA weather suspects that this temperature is not accurate. A hypothesis test is performed the determine

Introduction to Hypothesis Testing

Introduction to Hypothesis Testing State the claim mathematically. Then write the null and alternative hypothesis. Determine whether the hypothesis test is left-tailed, right-tailed, or two-tailed. a. A research hospital claims that more than 3.7% of the population suffers from high blood pressure. Use p, the represent

Applications of inference and hypothesis testing

In what areas of your business is it important to draw inference? Describe a time when drawing an inference may have hurt your business. What is the significance of a one-tailed test as opposed to a two-tailed test? Describe a set of data that is one tailed. Describe a second set that is 2 tailed.

Characteristics of Good Research Hypothesis

Discuss the characteristics of a good research hypothesis. What distinguishes a null hypothesis from a research hypothesis? How would you explain the difference between non-directional research and directional research hypothesis?