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Z-Test

Altmans z

Who would use Altman's Z score to predict bankruptcy? Why would the ability to predict bankruptcy be useful to them?

Z-score distribution

A distribution has a standard deviation of 0=4. Find the z-score for each of the following locations in the distribution. a. Above the mean by 4 points b. Above the mean by 12 points c. Below the mean by 2 points d. Below the mean by 8 points

Z-test for accident rates

In Dallas some fire trucks were painted yellow. During the test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents. the fleet of yellow trucks made 135,035 runs and had 4 accidents. At a=.01, did the yellow fire trucks have a significantly lower accident rate? Zc=2.326 Z=2.961 p-value=.0015 normal

Corresponding Z-Scores Percentiles

#1 With regards to a standard normal distribution complete the following: (a) Find P(z < 0), the percentage of the standard normal distribution below the z-score of 0. (b) Find P(z < 1.65), the percentage of the standard normal distribution below the z-score of 1.65 (c) Find P(-3 < z

Vehicle Mileage Statistical Analysis

The Environmental Protection Agency (EPA) fuel economy estimates for automobile models tested recently predicted a mean = 24.8 miles per gallon and a standard deviation a = 6.2 miles per gallon for highway driving. Assume a normal distribution. Use this information to answer questions #13 - #14. (13) Use Table 4 (Standard

Z test for population mean number of arrivals per hour

9.22 The mean arrival rate of flights at O'Hare Airport in marginal weather is 195 flights per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air traffic control procedure is implemented. In the next 30 days of marginal weather the mean arrival rate is 200 flights per hour. (a) Set up a rig

Hypothesis test for the difference of population means: Z test

Please see attached file for full problem. Hypothesis test for the difference of population means: Z test According to the historical data, the life expectancy in the United States is equal to the life expectancy in Japan. A new study has been made to see whether this has changed.

Another Special Cases of Z-scores

Briefly explain what percentages of the cases in the normal curve you can obtain by using a z-score of 2.58 as a cutoff point. Specifically: A. Discuss the percentages in the middle area (near the mean). B. Discuss the percentages in the tails.

Find the z value

What is the z value to the right of the mean such that 85% of the total area lies to the left?

Five-year old study claims that selling prices of new homes

A five-year old study claims that selling prices of new homes / condominiums in the New York area have a normal distribution with mean = $180,000 and standard deviation = $40,000. a. Assuming that the results of the study are still valid, what is the probability that a randomly selected new house in the New York area will cos

Analysis of a T-Test and Z-Test

Perform hypothesis testing on one variable's data. (Choose either the intrinsic or extrinsic column.) Perform a t-test by formulating a null and an alternative statement, choosing an acceptable significance value, selecting the test statistic and determining its value from the sample data, comparing the observed value to the cri

Standard Deviation Calculations

Find the standard deviation for the given data. Round your answer to one more decimal place than the original data. 54) 15, 42, 53, 7, 9, 12, 14, 28, 47 54) ______ A) 15.8 B) 29.1 C) 17.8 D) 16.6 Use the empirical rule to solve the problem. 55) The systo

One sample z test for population proportion.

The election is one week away. You think you have the election sewn up, but the seem appears to be unraveling. You run a poll, draw a random sample of 500 adults. 54% say they will vote for your candidate. Will your candidate win? Prove it.

Chebyshev: Normal Populations and testing

5. Consider an infinite population with a normal shape and a mean of 300 and standard deviation of 30. a. Compute the z-scores for the following values of X and locate each on the graph. X Z-score 200 360 220 270 300 b. According to the Empirical rule what percent of the data should be between 270 and 330? Betw

HYPOTHESIS TESTING

Here is a sample of 106 body temperatures (attached file) with a mean of 98.20 F. Assume that &#963; is known to be 0.62 F. Consider a hypothesis test uses a 0.05 significance level to test the claim that the mean body temperatures of the population is less than 98.6F. a. What is the test statistic? b. What is the critical

Finding probability using a normal distribution

1.) A normal distribution has a mean=60 and a standard deviation=6. Find the following probabilities: p(X>56) p(X<70) p(52<X<68) p(61<X<75) 2.) A normal distribution has a mean=35 and standard deviation=5. Find the scores associated with the following regions: a.) the score needed to be in the 43rd percentile. b.) T

Normal Probability Law

#1.) Dr.Radman has been collecting data on a simplified intake form. One measure that was taken was the amount of time (in minutes) it took people to complete this form. The time to complete the simplified form was Mean=22 minutes and Standard Deviation= 3 minutes (assume there were enough forms completed to justify using popula

Determination of Critical value, Significance level, p value for Z test

Question 1 (Basic Business Statistics Tenth Edition Q 7.53.) DiGiorno's frozen pizza has some of the most creative and likeable advertisements on television. USA Today's Ad Track claims that 20% of viewers like the ads "a lot"" (Theresa Howard, "DiGiorno Campaign Delivers Major Sales," www.usatoday.com, April 1, 2002). Su

When to use a t-test and when to use a z-test

When to use a t-test and when to use a z-test. How to choose between a t-test and a z-test, a one-sample test and a two-sample test, and a one-sided and a two-sided test. Lists the assumptions made about the sample and the population for each test.

Z test for Height of women in Sweden

I need to know the answer in Z test not student test (test statistic is t) which was highlighted in pink. See attached file for full problem description. I am planning my second trip to Sweden. Of course, I had read about the country and one article stated the average woman there is 69 inches tall with a standard deviation

Distributions, Standard Deviations and Z-Scores

4. James Johnson, manager of quality control at Creative Auto Corp., just received a report from the assembly plant. The latest shipment of 200 lug bolts used to attach the wheels showed a mean diameter of 18.01 mm and a median of 17.92 mm. Therefore, James can conclude that the distribution of the diameters of the lug bolts a.

Chi square test of independence and Z test

6. A researcher is interested in studying the relationship between certain driving habits and type of vehicle. He hypothesizes that signaling behavior will be different for drivers of trucks and cars. The data from observations made while driving are given below. Calculate the two-variable Chi-square test. State the null hypothe

Formulate Percentages for Architects with Z Scores

Suppose that the scores of architects on a particular creativity test are normally distributed. What percentage of architects have Z scores (a) above .10, (b) below .10, (c) above .20, (d) below .20, (e) above 1.10, (f) below 1.10, (g) above -.10, (h) below -.10?

Z-score given mean test score and standard deviation

A student scores 50 on a psychology exam and 83 on an economics exam. The psychology exam has a mean score of 60 and the standard deviation of 5. The economics exam has a mean score of 80 and a standard deviation of 10. Find the z-score for each test and decide which exam score is relatively better. What is the z-score for th

Calculate Ratios

The discussion part of the assignment is to discuss how investors will assess the stability of a fictitious company? What are the key financial ratios that measure the stability of an organization? Define stability. I need help with the part that says, "calculate these ratios" Please see attached.

Z-score of employees

Your boss has determined that on Wednesday, 5 random employees on the line to have a chance to obtain a $25 bonus if they produce more XT34's than 84% of all other employees on the line. Therefore, randomly choose five workers from the sample and determine if they will get a bonus. hint u will need to use a z-score. employee#/