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Hypothesis Testing

Two-Sample Tests and Evidence

A teacher claims that a grammar seminar will help students reduce the number of grammatical errors they make when writing a 1000-word essay. The table shows the number of grammatical errors made by seven students before participating in the seminar and after participating in the seminar. Student 1 2 3 4 5

Statistics regression anaylsis, Ho and null hypothesis

How do I determine sleep affect on GPA or is something else affecting grades as much, using statistics? Background There have been various studies that say students' grades are affected by poor diet, high amounts of stress, lack of sleep, and excessive alcohol use. Perhaps one of the most important factors out of those ment

Statistics of SPSS 2004GSS.sav data file

Crosstabulation: Examine variables in the "2004GSS.sav" data file. Choose one from the following three variables to be the dependent variable in the hypotheses you will establish. a. Grass b. Fear c. Gunlaw Choose another variable from the data

Statistical Tests: Hypotheses, Critical Region, and P-Value

Let p equal the proportion of drivers who use a seat belt in a country that does not have a mandatory seat belt law. It was claimed that p = 0.14. An advertising campaign was conducted to increase this proportion. Two months after the campaign, y = 104 out of a random sample of n = 590 drivers were wearing their seat belts. Was

Hypothesis Testing

1. What is the five step process for hypothesis testing? Why or why not? What is the null hypothesis? Why is it important? What are its implications? Explain. You may use examples to show your understanding. 2. Why is it said that hypothesis testing involves a double negative logic? Explain why you think that this logic is i

Modification Sample Means for LSD Test

10. Three Radar modifications were tested for detection range improvement using five trials each. The following single factor ANOVA Table presents the results: (See attachment for table) The modification (Mod) sample means are: Mod A = 31.4, Mod B = 28.6,Mod C = 23.8 Using the Fisher LSD test, determine if any of the


1. If 10% of a population of parts is defective, what is the probability of randomly selecting 80 parts and finding that 12 or more parts are defective? 2. A survey was taken of U.S. companies that do business with firms in India. One of the questions on the survey was: Approximately how many years has your company been tra

Hypothesis Testing for Teaching Style and Gender

Please see attached file for proper format and formulas. All work has to be shown. If using SPSS a copy of your output and data file has to be present. Please use formulas. Below is the data that has to be used to answer all of the questions. The participants were 30 statistics students that were randomly selected to parti

Hypothesis Testing

A finance professor claims that there is much more variability in the final exam scores of students taking the introductory finance course as a requirement than for students taking the course as part of a major in finance. Random samples of 16 non-finance majors (group 1) and 10 finance majors (group 2) are taken from the profes

Hypothesis Testing: Animal Bone & Rock Examples

1. Four animal bone samples were discovered in the ditch terminals. These bones bore signs of attempts at artificial preservation and might have been in use for a substantial period of time before being placed at Stonehenge. When dated, these bones had a mean age of 3187.5 BC and standard deviation of 67.4 years. Assume that the

Hypothesis Test

Stonehenge's main ditch was dug in a series of segments. Excavations at the base of the ditch uncovered a number of antlers which bore signs of heavy use. These antlers could have been used by the builders as picks or rakes. The fact that no primary silt was discovered beneath the antlers suggests that they were buried in the di

Rejection Region

How is the rejection region defined and how is that related to the z-score and the p value? When do you reject or fail to reject the null hypothesis? Why do you think statisticians are asked to complete hypothesis testing? Can you think of examples in courts, in medicine, or in your area?

Test null hypothesis

The spotlight effect refers to overestimating the extent to which others notice your appearance or behavior, especially when you commit a social faux pas. Effectively, you feel as if you are suddenly standing in a spotlight with everyone looking. In one demonstration of this phenomenon, Gilovich, Medvec, and Savitsky (2000) aske

Z test and hypothesis testing

Please help with the following problem. The mean waiting time for the drive-through window of a fast-food franchise is believed to be 3.7 minutes. A manager wants to check the time at her particular restaurant. A sample of 75 customers is selected and the sample mean waiting time is 3.57 minutes with a sample standard deviat

Statistical testing using a level of significance

System data for a job shop revealed that the average time spent by a job in the shop was approximately n = 5 working days. A random sample of size five is taken with time spent in the shop, 3.7, 4.6, 3.9, 4.1, and 3.8. Is the output consistent with system behavior? (Why?). Construct a statistical test using a level of signific

Conducting a test of hypothesis

a. Using the CIA data, attached. conduct a test of hypothesis to determine if the mean number of cell phones is greater than 4.0. Use teh .05 significance level. What is the p-value? b. Conduct the test of hypothesis to determine fi the mean isze of teh labor forces is less than 50. Use teh .05 significance level. Wh

Statistics of SPSS file

Perform appropriate statistics for each of the following variables in the data file "" 1) age, 2) gender, 3) race, and 4) class. The choice of statistics should be either percentage with bar chart (for categorical/discrete variables), or the mean and standard deviation for continuous/ratio variables. For categorical v

Consider a chemical company that wishes to determine whether a new catalyst

Consider a chemical company that wishes to determine whether a new catalyst, catalyst XA-100, changes the mean hourly yield of its chemical process from the historical process mean of 750 pounds per hour. When five trial runs are made using the new catalyst, the following yields (in pounds per hour) are recorded: 801, 814, 7

The Crown Bottling Company 2

The Crown Bottling Company has just installed a new bottling process that will fill 16-ounce bottles of the popular Crown Classic Cola soft drink. Both overfilling and underfilling bottles are undesirable: Underfilling leads to customer complaints and overfilling costs the company considerable money. In order to verify that the

Determine unit amount.

ABC Convenient stores uses fixed-time period model to determine order quantity for their popular chewing gum (Supergum). Daily demand for Supergum is 100 units with a standard deviation of 25 units. The review period is 10 days and lead time is 6 days. At the beginning of this review period there are 50 units in stock. If

Establishing a Hypothesis

Establishing a Hypothesis Open the SPSS data file "chicago.sav" and identify the following data information: 1. Use the data view to identify the units of analysis in this data set. 2. Use the variable view to identify a) the number of variables in this dataset, b) the meaning of variables "pliceex" and murderer". 3. Use the

Six Sigma Tools for Testing Statistical Significance in Sleep

Sam Sleep researcher hypothesizes that people who are allowed to sleep for only four hours will score significantly lower than people who are allowed to sleep for eight hours on a management ability test. He brings sixteen participants into his sleep lab and randomly assigns them to one of two groups. In one group he has partici

Problems involving the Hypothesis Testing of Means

1. From a population of cans of coffee marked "12 ounces," a sample of 50 cans was selected and the contents of each can were weighed. The sample revealed a mean of 11.8 ounces with a SAMPLE standard deviation of 0.5 ounces. a. Formulate the hypotheses to test alternative hypothesis that the mean of the population is less than

tables and analysis help

I need some help with a wilcoxon some help in the following. The group is for 65 teachers doing a pretest post and at 12 months knowledge quiz on diversity in the class room...I need the following test (wilcoxon with p value set at 0.05 and any explanation you can offer on any significant findings. I know there are differ

Statistical Analysis Hypothesis Help

The following data compares the statistics scores from 2 groups of students who were randomly sampled at the beginning of the study, and then randomly assigned to treatment conditions. One group of students was sleep-deprived and one group of students got a normal night's sleep. Sleep Normal Deprived Sleep 45 79 55 52 67 84

Statistic Help in SPSS

Statistical aptitude scores are known to be normally distributed, with mean = 50. A researcher has designed a new program intended to improve studentsââ?¬â?¢ statistical aptitude, and has enrolled a sample of 30 students in it. The researcher then collects studentsââ?¬â?¢ statistical aptitude scores at the end of the p