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Z-Test

Standard Scores in Populations

A population with u=73 and o=9 is transformed into a new population with u=10 and o=2. What is the new value for each of the following scores in the population? X=74 X=60 X=86

Computing probability problems related to temperature

If 0.5% of the thermometers are rejected because they have readings that are too low and another 0.5% are rejected because they have readings that are too high, find the two readings that are cutoff values separating the rejected thermometers from the others. Finding Temperature Values: Assume that thermometer readings are no

Sampling and Sampling Distributions

I need help with some practice problems that were given to us, to help prepare for a quiz next week. Please provide detailed steps as to how you came by your answer (include any notes, calculations, or anything that may be pertinent to the solution). As always, your help would be greatly appreciated! Thanks, E

Probabilities: Mean, Normal Distribution and Standard Deviation

Please help with the following problems. Among females in the United States between 18 and 74 years of age, diastolic blood pressure (DBP) is normally distributed with mean ? = 76 mm Hg and standard deviation ? = 10.2 mm Hg. a) What is the probability that a randomly selected woman has a DBP less than 65 mm Hg? b) What

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Consider the following hypothesis test: H0: p = .20 Ha: p (does not equal) .20 A sample of 400 provided a sample proportion beta = 0.175. a. Compute the value of the test statistic. b. What is the p-value? c. At alpha = 0.05, what is you conclusion? d. What is the rejection rule using the critical value? What is y

Testing the Difference: Two Means, Proportions and Variances

Please provide assistance in getting this z-test done. The chapter has to do with testing the difference between two means, two proportions, and two variances. Provide a professional report that addresses the question weather one of the teams has an average weight that is greater than the other team. Attached is the data.

Application of Z Score and Probability

Suppose that SAT score is normally distributed with a mean 988 and a standard deviation of 211 in 2004.A local college plans to set up a scholarship budget for 2005 where $5000 will be awarded to each incoming freshman whose SAT score is higher than 1500. They expect about 5000 applicants each year. What is the expected scholars

Random Variable, Probability and Distribution

1.The number of pizzas delivered to students each month is a random variable with the following probability distribution: X 0 1 2 3 P (x) 0.1 0.3 0.4 0.2 A) Find the mean number of pizzas delivered. B) Calculate the variance in the number of pizzas delivered. C) Determine the standard deviation. 2. It is

Explaining the Z-Score Statistic

Explain the difference between a positive z-score and a negative z-score. If you can give me an example that would be awesome. Thank you.

Descriptive Stats-additions, corrections, additions

Hi Martin! Here is the part I need your help, and I will also add the feedback below. 1) Compute the high scores on the RCMAS that would correspond to an extremely low score. 2) Demonstrate a conceptual understanding of z-scores in a write up. 3) Calculate the high and low score values **Include an interpretation of resul

Find the Z-Score for the Given Distributions

Find the z-score corresponding to a score of X = 100 for each of the following distributions: a. ? = 80 and ? = 10 b. ? = 80 and ? = 5 c. ? = 105 and ? = 10 d. ? = 105 and ? = 5 Make sure to indicate the direction (sign) of the z-scores.

The web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are exceeding their goal using a=.025?

Exercise 9.62 The web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are exceeding their goal using a=.025?

Descriptive statistics/ Describing variation Z-score

I need assistance I keep getting 2.53333 as an answer =(10-8.1)/0.75=2.53333 The problem is as follows: A pizza franchise specifies that the amount of cheese on a large pizza should be on average 10 ounces with a standard deviation of 0.75 ounces. An inspector measures the amount of cheese on a large pizza and finds the a

Proportion Testing with Z Test

What is the alternative hypothesis consistent with the claim the test subject is an expert? Which of the following is consistent with the rule for the null hypothesis and with the alternative: H0: p < 0.5 H0: p > 0.5 H0: p = 0.5 H0: p ? ?? 0.5 Why 0.5? What is the critical value for the test statis

Normal Distribution and Normal curve

Describe the basic characteristics of a normal distribution and the normal curve. What are z scores and how are they used in relation to distributions and raw scores? What is the difference between population and sampling distributions? Provide at least one example for each concept, explaining how the chosen example illustrates

Applied Statistics Health Care

I am new at a job and I have been given instructions that focused on Population and Sampling Distributions I need support in proving that the use of z-scores to describe the location of a score within a distribution and to standardize scores from different populations. In addition to that, I also need to explain basic probabi

Distribution Compare with his/her Z Score in Original Population

Using z-scores, a population with µ = 37 and Ï? = 6 is standardized so that the new mean is µ = 50 and Ï? = 10. How does an individual's z-score in the new distribution compare with his/her z-score in the original population? cannot be determined with the information given new z = old z + 13 new z = (10/6)(old z)

Statistical Analysis

Student ID IQ SCORE GPA 1 84 2.5 2 71 2.1 3 62 1.9 4 89 3.1 5 66 1.9 6 109 3.5 7 107 3.2 8 92 3.3 9 67 2 10 112 3.4 11 74 2.5 12 66 2 13 103 2.9 14 114 3.1 15 76 2.2 16 97 2.9 17 70 2.6 18 108 3.9 19 66 1.8 20 88 2.8 21 113 3.8 22 107 3.5 23 82 3 24 110 3.6 25 94 2.9 26 76 2.4 26 82 2.9 28 74 2 29 88

Quantitative Methods

The Webster National Bank is reviewing its service charge and interest-paying policies on checking accounts. The bank has found that the average daily balance on personal checking accounts is $550, with a standard deviation of $150. In addition, the average daily balances have been found to be normally distributed (Gauss

Z-score sets and meaning

Compute the z-score from the following set of scores and explain what a z-score means. 145; 210; 300; 178; 110; 237; 155; 187; 204; 205; 205; 287; 256; 200

Statistics Problems

Descriptive Statistics 1. The table below presents data for a sample of people who completed a religious survey. Age Gender Denomination Church Attendance 56 1 7 4 46 2 6 5 49 2 6 5 49 1 1 5 27 2 9 5 51 1 4 2 47 2 2 3 67 1 5 4 49 2 2 6 33 1 12 6 55 2 9 5 40 1 7 5 62 1 8 6 47 2 6 3 56 2 9 5 22 1 10 2 50 2

Probability calculation using Z score..

A clinical study was performed to determine if a product was effective in alleviating side effects caused by a mode of treatment. In the treated group (100 subjects) it was found that 10% had side effect A, 15% had side effect B and 65% had side effect C. In the untreated group (1000 subjects) the same side effects occurre

Long term effects of preschool programs for poor children

To study the long term effects of preschool programs for poor children, the High/Scope Educational Research Foundation has followed two groups of Michigan children since early childhood. One group of 62 attended preschool as 3 and 4 year olds. A control group of 61 children from the same area and similar backgrounds did not at

Inference about a Population Proportion for doctor assisted suicide

A Gallup Poll asked a sample of Canadian adults if they thought the law should allow doctors to end the life of a patient who is in great pain and near death if the patient makes a request in writing. The poll included 270 people in Quebec, 221 of whom agreed that doctor assisted suicide should be allowed. (a) What is the m

Hypothesis Testing of Proportions: Two sample Z Test

A committee studying employer-employee relations proposed that each employee would rate his or her immediate supervisor and in turn the supervisor would rate each employee. To find reactions regarding the proposal, 120 office personnel and 160 plant personnel were selected at random. Seventy-eight of the office personnel and 90

Probability based on Z score..

I need easy step by step instructions of how to do the following word problem. A) A battery manufacturer advertises the average life of its automobile battery is 60 months.what % of batteries should last between 50 and 70 months? The standard deviation is 10 months. B) If you purchased a battery and it lasted only 23 months

Statistics

7. A researcher is interested in comparing the response times of two different cab companies. Companies A and B are each called at 50 randomly selected times. The calls to the company A are made independently of the calls to company B. The response times for each call are recorded. The summary statistics are as follows Compa

Test mean aptitude test scores of two groups of freshman students

The mean score for freshman on an aptitude test at a certain college is 800 with a standard deviation of 50. That is the probability that two groups of students selected at random, consisting of 36 and 49 students, respectively, will differ in their mean scores by: (Assume mean scores are continuous) a) more than 12 points?

Calculation of Z Score using the Standard Normal

Consider a population with m(mean)=93.3 and s(standard deviation)=5.27 (A) Calculate the z-score for x =94.9 from a sample of size 12. (B) Could this z-score be used in calculating probabilities using a standard normal distribution table? Why or why not?