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Hypothesis Testing

Test a Claim About a Mean for weight loss: Sigma Not Known

Is the Diet Practical? When 40 people used the Weight Watchers Diet for one year, their mean weight loss was 3.0 lb and the standard deviation was 4.9 lb. Use a 0.01 significance level to test the claim that the mean weight loss is greater than 0 lb. Based on these results, does the diet appear to be effective? Does the diet app

Hypothesis t testing problems

Question #1 / 9 The mean SAT score in mathematics is . The founders of a nationwide SAT preparation course claim that graduates of the course score higher, on average, than the national mean. Suppose that the founders of the course want to carry out a hypothesis test to see if their claim has merit. State the null hypothesis

conclusion about statistical significance

In Exercise 23-26, form a conclusion about statistical significance. Do not make any formal calculations. Either use results provided or make subjective judgments about the results. 24. Mendel's Genetics Experiment One of Gregor Mendel's famous hybridization experiments with peas yielded 580 offsprings with 152 of those peas


14. 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 (indiv

Hypothesis Testing of Mean: FICO credit rating scores

See attached file. Data set attached includes a simple random sample of FICO credit rating scores. As of this writing, the Mean FICO score was reported to be 678. Use a 0.05 significance level to test the claim that the sample of FICO scores comes from a population with a mean equal to 678. H0: H1: Test Statistic [S

Test a Claim about a Proportion in a stem cell survey

Stem Cell Survey - Adults were randomly selected for a Newsweek poll. They were asked if they "favor or oppose using federal tax dollars to fund medical research using stem cells obtained from human embryos." Of those polled, 481 were in favor, 401 were opposed, and 120 were unsure. A politician claims that people don't really u

Statistics: Testing a Claim About a Proportion of arrests

Percentage of arrests - A survey of 750 people aged 14 or older showed that 35 of them were arrested within the last year. Minitab was used to test the claim that fewer than 5% of people aged 14 or older were arrested within the last year. Use the results from the Minitab display and use a 0.01 significance level to test the sta

Cans of regular and diet Coke have the same mean weight

See attached file for complete formulas. 2. Below is the summary information for the weights (in pounds) of regular Coke and diet Coke cans. Test the claim that cans of regular Coke and diet Coke have the same mean weight at a 0.01 level of significance. Regular Coke Diet Coke n1=36 n2=36 s1=0.007507 s2=0.0004391

Reversal - Null and Alternative Hypotheses

1. In the 2000 football season, 247 plays were reviewed by officials using instant video replays, and 83 of them resulted in reversal of the original call. In the 2001 football season, 258 plays were reviewed and 89 of them were reversed. Test the claim that the proportion of plays reversed is different for the 2000 and 2001 s

Statistics Hypothesis Testing & One sample tests

See attachment for complete problems. Week 1: Quiz: Hypothesis Testing & One sample tests Due on March 8, 2010 in your Individual Forum Directions: For the following one-sample tests, identify the null and alternative hypothesis, and the critical value. Then, calculate the test statistic, note the p value and make a deci

Hypothesis Testing problems

13. For each of the following: (a) State which two populations are being compared (b) State the research hypothesis (c) State the null hypothesis (d) Say whether you should use a one-tailed or two-tailed test and why. i. In an experiment, people are told to solve a problem by focusing on the details. Is the speed of

Statistics Null hypothesis: 20% of Pennsylvania households make more than $70,000

An economic researcher would like to know whether he can reject the null hypothesis at the 0.10 level, that no more than 20% of the households in Pennsylvania make more than $70,000 per year. a. If 200 Pennsylvania households are chosen at random, how many of them would have to be earning more than $70,000 per year for the r

Stating Conclusions about Claims

In these questions we have to make a decision about the given claim. For example, if the claim is that a coin favors heads and sample results consists of 11 heads in 20 flips, conclude that there is not sufficient enough evidence to support the claim that the coin favors heads. 6) Claim: The proportion of households with tele

Null hypothesis and Alternative hypothesis

You work at a hospital that has always had about 100 emloyees staffed at night. You think that the number of employees staffed at night has recently decreased and would like to test this claim. If you run a hypothesis test, which of the following statements would fit your problem? a) you have a two tail test. b) your alter

Life Expectancy and Literacy Rate: Comparing Results Example

See attached data set file. Do countries where the life expectancy is 65 years and older have a higher literacy rate? Describe the results of your test, and explain how the findings from this hypothesis testing can be used to answer your research question. Be sure to include your raw data tables and the results of the comp

Hypothesis Testing and Rejection Region: Horse Example

Is there a significant difference between the lengths of front and rear legs of a certain breed of horses. The results of the measurements in inches made in 10 of these animals are: No. of copies 1 2 3 4 5 6 7 8 9 10 Long. Foreleg 138 136 147 139 143 141 143 145 136 146 Long. Hind l

Hypothesis testing: Double negative logic, five step process

Can someone explain this material to me in simple terms? (1) Explain the double-negative logic of hypothesis testing (eg: a scientist fails to reject the null hypothesis). (2) What is the five-step process for hypothesis testing? Is the order important? Why or why not?

Statistics tests with conclusions: Florida lot price; Microsoft Outlook users

Problem 6 The Chamber of Commerce of a Florida community advertises that area residential property is available at a mean cost of $25,000 or less per lot. As a part-time resident, you believe this to be an untrue statement and you seek to test the validity of this claim at the .05 level of significance. You collect a sample o

Upper and Lower Control Limits for Testing

The yield strength of a metal bolt has a mean of 6,050 pounds with a standard deviation of 100 pounds. Twenty samples of three bolts were tested, resulting in the means shown below. (a) Construct upper and lower control limits for the¯ x chart, using the given product parameters. (b) Plot the data on the control chart. (

ANOVA: Apple juice concentrate

See attached file. An apple juice manufacturer develops a new juice concentrate. This new product is a) more convenient, b) higher in quality, and c) less expensive than conventional apple juice. The marketing manager needs to decide whether advertising should stress convenience, quality, or price. A pilot study is done in th

Interpretations of P value

(a) A statistical study reported that a drug was effective with a p-value of .042. Explain in words what this tells you. (b) How would that compare to a drug that had a p-value of .087?

Hypothesis Testing: Population proportion

Please explain how you obtained your results. 1. A student wants their College to offer Kickboxing classes as a Physical Education class. To justify that the class is desired he surveys 200 students and finds that 56% would be interested in taking the class. He goes to his Dean and tells him that based on his survey over h

Statistics: Difference in mean selling price of homes

A recent MBA graduate is trying to decide between two job offers, one in Omaha and one in Kansas City. One factor affecting his decision is the cost of a new home in each city. A recent study sampled 88 new home sales in the Omaha area and found that the mean selling price of a new home was $183,900 with a standard deviation o

Significance level

23. A real estate agent in the coastal area of Georgia wants to compare the variation in the selling price of homes on the oceanfront with those one to three blocks from the ocean. A sample of 21 oceanfront homes sold within the last year revealed the standard deviation of the selling prices was $45,600. A sample of 18 homes, al