"Normal Distribution" Essays and Research Papers

Normal Distribution

standard deviation = square root of variance = sqrt(846) = 29.086 4. If we have the following data 34, 38, 22, 21, 29, 37, 40, 41, 22, 20, 49, 47, 20, 31, 34, 66 Draw a stem and leaf. Discuss the shape of the distribution. Solution: 2 3 4 5 6 | | | | | 219200 48714 0197 6 This distribution is right skewed (positively skewed) because the “tail” extends to the right. 5. What type of relationship is shown by this scatter plot? 45 40 35 30 25 20 15 10 5 0 0 5 10 15 20 Solution: Weak positive linear...

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Normal Distribution

decimal places) 2. Find the value of z if the area under a Standard Normal curve a) to the right of z is 0.3632; b) to the left of z is 0.1131; c) between 0 and z, with z > 0, is 0.4838; d) between -z and z, with z > 0, is 0.9500. Ans : a) z = + 0.35 ( find 0.5- 0.3632 = 0.1368 in the normal table) b) z = -1.21 ( find 0.5 – 0.1131 = 0.3869 in the normal table) c ) the area between 0 to z is 0.4838, z = 2.14 d) the area to the...

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Normal Distribution and Random Sample

points) 3. Suppose that a random sample of size 64 is to be selected from a population having [pic] and standard deviation 5. (a) What are the mean and standard deviation of the [pic] sampling distribution? Can we say that the shape of the distribution is approximately normal? Why or why not? (10 points) (b) What is the probability that [pic] will be within 0.5 of the population mean? (5 points) (c) What is the probability that [pic] will differ from the population...

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Computational Aspects of Normal Distribution

•H.P.Gautam The purpose of this article is not to explain any more the usefulness of normal distribution in decision-making process no matter whether in social sciences or in natural sciences. Nor is the purpose of making any discussions on the theory of how it can be derived. The only objective of writing this article is to acquaint the enthusiastic readers (specially students) with the simple procedure ( iterative procedure) for finding the numerical value of a normally distributed variable. The...

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Normal Distribution and Multiple Vitamin

skewed-right distribution with a mean of 10 minutes and a standard deviation of 8 minutes. Suppose 100 flights have been randomly sampled. Describe the sampling distribution of the mean waiting time between when the airplane taxis away from the terminal until the flight takes off for these 100 flights. a) Distribution is skewed-right with mean = 10 minutes and standard error = 0.8 minutes. b) Distribution is skewed-right with mean = 10 minutes and standard error = 8 minutes. c) Distribution is approximately...

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Statistics: Normal Distribution and Data

or variability of the data about the measurements of central tendency. MEASUREMENTS OF CENTRAL TENDENCY The appropriateness of using the mean, median, or mode in data analysis is dependent upon the nature of the data set and its distribution (normal vs non-normal). The mean (denoted by x) is calculated by dividing the sum of the individual data points (where Σ equals “sum of”) by the number of observations (denoted by n). It is the arithmetic average of the observations and is used to describe...

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Normal Distribution and Population Mean

at Weston Materials, Inc., a national manufacturer of unattached garages, reports that it takes two construction workers a mean of 32 hours and a standard deviation of 2 hours to erect the Red Barn model. Assume the assembly times follow the normal distribution. a. Determine the z values for 29 and 34 hours. What percent of the garages take between 32 hours and 34 hours to erect? z(29) = (29-32)/2 = -3/2 z(34) = (34-32)/2 = 1 z(32) = 0 P(32 < x < 34) = P(0< z < 1) = 0.34 b. What percent of...

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Assignment: Normal Distribution and Business Forecasting

with an example 2 2 10 6 a) Describe the characteristics of Normal probability distribution. b) In a sample of 120 workers in a factory, the mean and standard deviation of wages were Rs. 11.35 and Rs.3.03 respectively. Find the percentage of workers getting wages between Rs.9 and Rs.17 in the whole factory assuming that the wages are normally distributed. Characteristics of Normal probability distribution Formula/Computation/Solution to the problem 3 4 10 6 a) The...

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Variances: Normal Distribution and Budget Cash Figure

(However in large organisations it is normal to allow for the impact of a disaster centrally as a contingency even if it is not budgeted at operating unit level.) If necessary, insurance should be taken out. If business is disrupted for two weeks, then it is pointless to compare the remaining two weeks of the month against a full month's budget. Produce a realistic budget for only two weeks and compare against that to establish true performance under normal circumstances. 4. Differences between...

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Normal Distribution and Points

 STAT 200 Section 7983   Sping 2012 `  Quiz #2   Please answer all 6 big questions.  The maximum score for each question is posted at the beginning of the question, and the maximum score for the quiz is 60 points.  Make sure your answers are as complete as possible and show your work/argument.  In particular, when there are calculations involved, you should show how you come up with your answers with necessary tables, if applicable.  Answers that come straight from program software packages...

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Normal Distribution

 Normal Distribution Normal distribution is a statistics, which have been widely applied of all mathematical concepts, among large number of statisticians. Abraham de Moivre, an 18th century statistician and consultant to gamblers, noticed that as the number of events (N) increased, the distribution approached, forming a very smooth curve. He insisted that a new discovery of a mathematical expression for this curve could lead to an easier way to find solutions...

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Normal Distribution

NORMAL DISTRIBUTION 1. Find the distribution: a. b. c. d. e. f. following probabilities, the random variable Z has standard normal P (0< Z < 1.43) P (0.11 < Z < 1.98) P (-0.39 < Z < 1.22) P (Z < 0.92) P (Z > -1.78) P (Z < -2.08) 2. Determine the areas under the standard normal curve between –z and +z: ♦ z = 0.5 ♦ z = 2.0 Find the two values of z in standard normal distribution so that: P(-z < Z < +z) = 0.84 3. At a university, the average height of 500 students of a course is 1.70 m; the standard...

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Standard Deviation

Dispersion • Indicates how widely the scores are dispersed around the central point (or mean.) -Standard deviation Standard Deviation. • The most commonly used method of dispersion in oral hygiene. • The larger the standard deviation, the wider the distribution curve. Standard Deviation • SD,  ,  (sigma) • Indicates how subjects differ from the average of the group/ the more they spread out, the larger the deviation • Based upon ALL scores, not just high/low or middle half • Analyzes descriptively...

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Stats Equations

Sampling Distributions Sampling Error = x̄ - μ Z-Values for a sampling distribution of x̄ : Z = Z-Values adjusted with Finite Population Correction Applied if: the sample is large relative to the population (n is greater than 5% of N) and sampling Is without replacement Z = Using the Sampling Distribution for Means Compute the Sample Mean Define the sampling distribution μx̄ = Define the probability statement of interest P(z30 will give sampling distribution that is nearly normal fairly...

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Omis 41 Statistics Study Guide

confident the proportion is in this interval… if the sample mean or proportion is in the confidence interval the null hypothesis could be inferred. Else, the alternative hypothesis would. • What is the predictable distribution for proportions? Why? “Proportions follow a normal distribution provided: n·p ≥ 5 and n·(1– p) ≥ 5 ( Rule of 5 ) Thus the test statistic that we use is: • Can 1000 people represent 2 million? Why? Yes, depends how confident you want to be… to be +or- 1% (95% confident) ...

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procedures that do not rely on assumptions about the shape or form of the probability distribution from which the data were drawn.(1) Several fundamental statistical concepts are helpful prerequisite knowledge for fully understanding the terms “parametric” and “nonparametric.” These statistical fundamentals include random variables, probability distributions, parameters, population, sample, sampling distributions and the Central Limit Theorem.(2) II. Summary of the major points and how they might...

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Psychology Free Response Questions

tendency (mean, median, and mode). • Describe a skewed distribution. • Relate the three measures of central tendency to a normal distribution. • Relate the three measures of central tendency to a positively skewed distribution. • An intelligence test for which the scores are normally distributed has a mean of 100 and a standard deviation of 15. Use this information to describe how the scores are distributed. • In two normal distributions, the means are 100 for group I and 115 for group II. Can...

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Buisness Statatis

Q. Explain the term Sampling distribution The term sampling distribution refers to a frequency or probability distribution of the sample statistic obtained from all the possible samples of size n taken at random from a given population. The sample mean (x) shows the average value calculated from measurements of a sample. Its main characteristics are: 1. The average of all sample means should equal to the true population mean (µ) 2. The standard deviation shows dispersion...

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WGU MSN paper

distinguish experimental methods from correlational methods   Displaying Data (Chapter 2 – Munro e-Book)   Know what a distribution is and why examining a distribution can be helpful/useful Know how to interpret information from: Simple frequency distributions (grouped & ungrouped*) Relative frequency distributions (proportions* & percents*) Cumulative frequency distributions*             Histograms Bar graphs*             Stem-and-leaf displays You also should know how to construct those...

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QNT 561 Final Exam

often? A. Mean B. MedianC. ModeD. Geometric mean 4) Which level of measurement is required for the median? A. Nominal B. OrdinalC. IntervalD. Ratio 5) The mean and the variance are equal in…A. the normal distributionB. the binomial distributionC. the Poisson distributionD. the hypergeometric distribution 6) The difference between the sample mean and the population mean is called the…A. margin of errorB. population standard deviationC. standard error of the meanD. sampling error 7) A dummy variable...

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Ski Jacket Production

the uncertainty in estimated demand and provide insights of the range of profit outcomes and its associated risk (deviation from mean). The key issue is to understand impact of demand uncertainty and production level to the profit range and its distribution. In this case, we will determine the optimal decision variables (jacket production quantity) that will maximize our objective (average profit). The given information from management is the variable production cost, the selling price, and the...

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ECON 2P91 Assignment 1

excess kurtosis is 0.208336. For the normal distribution, skewness is zero. Since the skewness for SCORE variable is negative, this indicates that the distribution is skewed to the left (the long tail will be in the negative direction). For the normal distribution, kurtosis is three. So K-3 measures excess kurtosis. Since the excess kurtosis for SCORE variable is positive, the distribution is leptokurtic (it has thick tails as compared to the normal distribution. Summary Statistics, using the observations...

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Inferential Statistics

sample statistic and its corresponding population parameter. Chapter 3 : Sampling distribution Learning objectives ❖ What is sampling distribution ❖ Standard error of statistic ❖ Sampling distribution of sample mean ❖ When population has non-normal distribution o Central limit theorem ❖ When population has normal distribution What is sampling distribution ❖ It is a probability distribution consisting of all possible values of a sample statistic ❖ If, from a given population...

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Isb Assignment

a) Develop a ‘user friendly’ pie chart to illustrate the country distribution of the top 100 female tennis players. Briefly comment on your graph. User friendly pie chart * Slightly more than half of female players are from 7 countries, namely Australia, Czech Republic, France, Italy, Russia, Spain and United States. The remainders are from other countries. As can be seen in the graph of country distribution of the top 100 female tennis players, Russia have the highest proportion...

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Practice Midterm Exam (Statistics)

assumptions. Solution: (1) Assume that the difference [pic]is normal. [pic] and [pic] The hypotheses are [pic] v.s [pic]. The test statistic is [pic] Since [pic] and [pic], we can not reject [pic] at [pic]. [pic] (2) The SAS code is as follows: data hypnosis; input subject rest work @@; diff=work-rest; datalines; 1 6 6 2 7 9 3 8 9 4 7 10 5 6 7 ; run; proc univariate data=hypnosis normal; var diff; run; 2 (for all students in class). John Pauzke...

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CFA1 Quans

Quantitative methods Time value of money Effective annual rate (EAR) Effective annual rate (EAR) = (1+stated annual rate/frequency, m) ^ m-1 Annuities Ordinary annuities: cash flow at the end of each period, normal one; Annuities due: cash flow at the beginning of each period, first payment =t0; Calculator setting: [2nd][BGN]-[2ND][SET]; same procedure for setback to END; Payment at beginning of next three years, N=4, always +1 using annuities due It is a BGN question, if first payment is today...

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Electrical Installations Electrical apparatus and wiring systems are to be constructed and installed in accordance with the requirements of this Section. Standard Distribution System The following are recognized as standard systems of distribution. Distribution systems differing from these will be specially considered. • Two-wire direct current • Three-wire direct current • Two-wire single-phase alternating current • Three-wire three-phase alternating current • Four-wire three-phase...

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Stats Paper

office correct? (A) 6.6% (B) 76.4% (C) 83% (D) 92% 13. The _____________distribution would most likely be used to describe the distribution of arrivals to a grocery store and the _____________ distribution would most likely be used to describe the time between arrivals of customers to the grocery store. (A) Binomial, Normal (B) Poisson, Exponential (C) Normal, Binomial (D) Exponential, Poisson (E) Binomial, Poisson 14. Which of the following statements are true? (I) Mutually exclusive...

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the direction of variation of the data set. Definition: Skewness is a measure of symmetry, or more precisely, the lack of symmetry. A distribution, or data set, is symmetric if it looks the same to the left and right of the center point. Types of Skewness: Teacher expects most of the students get good marks. If it happens, then the cure looks like the normal curve bellow: But for some reasons (e. g., lazy students, not understanding the lectures, not attentive etc.) it is not happening. So...

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Applied Science

undergraduate English majors The sample is the Shakespearean play that was almost relevant in the year 2000. 3. Make a frequency distribution of the data set using five classes. The data set represents the income (in thousands of dollars) of 20 employees at a small business. 30 28 26 39 34 33 20 39 28 33 26 39 32 28 31 39 33 31 33 32 Answer: Frequency Distribution Table Income (in thousands of dollars) Frequency 20 1 26 2 28 3 ...

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Markdown Pricing Optimization at Bloomindales

consider doing non-parametric inference since non-parametric inference makes no assumptions about the underlying probability distribution. Since the consultants gave confidence intervals for β’s, they assumed that the underlying probability distribution was normal. While this may be valid, no information was given to verify this assumption. In order to verify that the data is normal, we could for example run an Anderson Darling Test. At the very least, a goodness of fit test should have been run to determine...

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Statistic Case Study for Bottle Company

percent can be found using a normal distribution calculator. The Z distribution is used in this case study because there are thirty bottles. The Z value is greater than or equal to thirty within the sample size. The Z value of 95 percent is 1.96. This represents the area on the normal distribution chart between the cutoff points. The cutoff points on the chart are between -1.96 and 1.96. The lower and upper limit will be given to locate the interval using the standard normal confidence interval. Calculate...

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EED 280 – Standards, Observation, Assessment: 0 - 8 (37317)

Why are tests with dual referencing difficult to design? 3. Why is a normal curve used to chart the distribution of test scores? 4. What is the function of the mean on the normal curve? the normal curve represents the ideal normal distribution of test scores of people, as well as the distribution of many other human characteristics 5. How do standard deviations serve...

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Measures of Central Tendency: Mean Medium Mode

Variables Range = Largest number minus smallest number SD = Average Distance from the Mean (Most frequently used) Variance: Fat & Skinny Distributions: Skewness – measure of the lack of symmetry, or the lopsidedness of a distribution. One “tail” of the distribution is longer than another. Kurtosis: has to do with how flat or peaked a distribution appears/ Platykurtic: flat Leptokurtic: peake Hypotheses Null Hypothesis: There is NO RELATIONSHIP between our IV and DV Non-Directional...

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69% of the sample taken of guests have incomes above $100,000. (138 out of 200) Whilst there is a minority of 31% of guests that earn less than $100,000. (62 out of 200) Size of Bookings Figure 2 presents a bi-modal distribution with people sizes of 2 people and 4 people being the pre-dominant classes. This shows the ability of CCResort to attract couples and families. Age of Booking Customer Figure 3: Histogram displaying the frequency of booking...

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Dmt Analysis

month had a major impact on the profit rather than the cost per unit. Chapter Three Analysis Based on problem 8, which data set is more stable. Base your answer on standard deviation values. Compare both frequency histograms and which shows a normal distribution behavior? The standard Deviation comparing both sets of data only shows a slight difference on the numbers (a difference of only 1.38187054), but in the histograms both show a huge difference on the frequencies of each data set, but shows...

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Final Exam Study Guide

It contains practice questions, which are related to each week’s objectives. In addition, refer to each week’s readings and your student guide as study references for the Final Examination. Week One: Descriptive Statistics and Probability Distributions Objective: Compute descriptive statistics for given data sets. 1. In 1995, the cost of unleaded gasoline was $0.95 per gallon. In 2010, the same type of gasoline costs $3.00 per gallon. To determine the amount of change, we have to use the ...

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Session III Quiz

have knowledge of unauthorized aid on this or [assignment, quiz, paper, test]. 2 Pg 212 #14) A normal population has a mean of 12.2 and a standard deviation of 2.5. A) Compute the z value associated with 14.3. - z = (14.3 – 12.2)/2.5 z value is .84 B) What proportion of the population is between 12.2 and 14.3? - Looking for .84 on the curve...

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Mr Cheng

| |Applications |In industries where large numbers of similar machines and workers engaged on similar tasks are employed. | |Underlying Principle |The theory of activity sampling is based on the laws of probability and binomial distribution. The concept| | |is that the characteristics of a large enough, yet unbiased sample chosen at random would be | | |representative of the population characteristics. ...

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Numerical and Verbal Hypothesis Statement

equal to the national average of $221,103, then Ho (or the null hypothesis) must be accepted. Using the estimated cost of San Diego houses, $300,000, we were able to calculate and confirm the results of the hypothesis test using the z-score normal distribution formula. Although the population standard deviation is unknown, we were able to use the sample standard deviation and calculate the z-score because the sample size is greater than 30. The findings from this hypothesis can be used to answer...

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Qnt 561 Week 2 Problem Set

States is $110,000. This distribution follows the normal distribution with a standard deviation of $40,000. A. If we select a random sample of 50 households, what is the standard error of the mean? σ/√n = 40000/√50 = 5656.85 B. What is the expected shape of the distribution of the sample mean? “The central limit theorem states that, for large random samples, the shape of the sampling distribution of the sample mean is close to the normal probability distribution” “Most statisticians consider...

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in response to the independent variable. Qualitative Variable - a variable based on categorical data. Quantitative Variable - a variable based on quantitative data. Graphs - visual display of data used to present frequency distributions so that the shape of the distribution can easily be seen. Bar graph - a form of graph that uses bars separated by an arbitrary amount of space to represent how often elements within a category occur.  The higher the bar, the higher the frequency of occurrence. ...

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Operations Management

Deviation σ = 24.24 s The fraction of days when hold time exceeded 110 s = P(x&gt;110) =? Mean of a distribution (μ) and a data point (x) is related by the following equation: x = μ ± zσ For x &gt; 110 s; XY Value of XY is area under normal curve between z = 0 to z = 0.43. Thus, approximately 1/3 or 0.336of days the call center failed to meet the targeted hold time. On the frequency distribution table this fraction is represented as 240/731 = approximately 1/3. -----------------------------...

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Visual Data Displays and Uses in Decision Making

for medical intervention in congestive heart failure, the use of the measure of central tendency is correct in this study. According to Bennett, Briggs, &amp; Thiola, (2009), “variation is a measure of how much the data values are spread out. A distribution in which most data are clustered together has a low variation.” (p. 16). In the article, “predicting need for intervention in individuals with congestive heart failure using a home-based Tele-care monitoring system for 18 months” (Biddiss, Brownsell...

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Statistics 1 course notes

and Y vary together. SPxy = ∑ [(X - Mx) * (Y - My)] r = SPxy / sqrt (SSx * SSy). SSx, SSy are measures of the degree to which X and Y vary independently. Z score formula: r = ∑ (Zx * Zy) / N Covariance = SP / N Assumptions for r: 1) normal distribution of X and Y - check histograms 2) linear relationship between X and Y - check scatterplots 3) homoscedasticity - vertical distance between scatterplot dots and regression line; indicates level of prediction error (aka “residual”) Measurement ...

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Assignment 2 Worksheet

between the speed and the gas mileage. What does it mean? 4- Compute the correlation coefficient between the speed and the gas mileage. What does it mean? 5- Graph a histogram of speed. Comment on the distribution of the speed. 6- Graph a histogram of gas mileage. Comment on the distribution of the mileage. II. Descriptive Statistics 1. For each variable (speed and mileage) in the table above, find mean, median, and mode. Mean Speed = Median X = Mode X = Mean Mileage = ...

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below. Part A 1. Why is a z score a standard score? Why can standard scores be used to compare scores from different distributions? 2. For the following set of scores, fill in the cells. The mean is 74.13 and the standard deviation is 9.98. Raw score Z score 68.0 ? ? –1.6 82.0 ? ? 1.8 69.0 ? ? –0.5 85.0 ? ? 1.7 72.0 ? 3. Questions 3a through 3d are based on a distribution of scores with and the standard deviation = 6.38. Draw a small picture to help you see what is required. a. What is the...

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Qnt 351 Final Exam Answers

Nominal B. Ordinal C. Interval D. Ratio 8) Monthly commissions of first-year insurance brokers are $1,270, $1,310, $1,680, $1,380, $1,410, $1,570, $1,180, and $1,420. These figures are referred to as A. a histogram B. raw data C. frequency distribution D. frequency polygon 9) A small sample of computer operators shows monthly incomes of $1,950, $1,775, $2,060, $1,840, $1,795, $1,890, $1,925, and $1,810. What are these ungrouped numbers called? A. Histogram B. Class limits C. Class frequencies ...

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Barron's Ap Statistics

Display the Barron’s guide discusses the different types of graphs, measures of center and spread, including outliers, modes, and shape. Summarizing Distributions mentions different ways of measuring the center, spread, and position, including z-scores, percentile rankings, and the Innerquartile Range, and its role in finding outliers. Comparing Distributions discusses the different types of graphical displays and the situations in which each type is most useful or appropriate. The section on Exploring...

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Econ 306 Hw Solutions

with colleagues in the class. But the assignment you turn in needs to be your own work. You should show some (though not necessarily every bit) of work for any substantial calculations. 1. (Each part 5 points) Suppose . That is, X has a normal distribution with μ=30 and σ2=144. 1a. Find a transformation of that will give it a mean of zero and a variance of one (ie., standardize ). Let the transformed variable be named Z. We desire μz=0, σ2z=1. This means 0=a+b μX and b2 σ2X=1. One solution...

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Flow Chart

5________________________ 1) Use the standard normal distribution to find P(-2.25 < z < 1.25). A) .0122 B) .8821 C) .8944 D) .4878 P(-2.25 < z < 1.25) = F(1.25) - (1 - F(2.25)) = 0.89435 - (1 - 0.987776) = 0.882126 2) Before a new phone system was installed, the amount a company spent on personal calls followed a normal distribution with an average of $ 900 per month and a standard deviation of $50 per month. Refer to such expenses as PCE's (personal call expenses). Using the distribution above, a. what is the probability...

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Study Questions Ch5 6 7 9

590 from the binomial probability distribution table or using the binomial formula. Chances are 50-50 that a newborn baby will be a girl. For families with five children, what is the probability that all the children are girls?  Answer: Given that probability of success is 0.50 P(X = 5) = 0.031 from the binomial probability distribution table or using the binomial formula. 4) Which of the following is NOT a characteristic of a binomial probability distribution?  A. Each outcome is mutually exclusive...

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Statistics Project

percentage. Let us examine the distribution of the vertical leap measurements, through a boxplot: The median is 36. The first and third quartiles are 34.25 and 38, with a minimum and maximum of 28.5 and 41. The distribution is fairly even, but ever so slightly skewed to the right. One indicator of a nearly normal distribution is that the mean is 35.86, which is very near to the median of 36. Also, there are only two outliers. We should also examine the distribution of field goal percentages through...

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math 112

driven on the average 23500 kilometers per year with a standard deviation of 3900 kilometers. Construct a 99% confidence interval for the average number of kilometers an automobile is driven annually in Virginia. Sol: 99% confidence interval, z distribution can be used N=100 ̅ ̅ ̅ √ √ 3. (9-58) An article in the ASCE Journal of Energy Engineering (1999, Vol. 125, pp. 59–75) describes a study of the thermal inertia properties of autoclaved aerated concrete used as a building material...

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Ll Beans

in cases, there is mismatch beyond 50% between the forecast and the actual demand. Besides the mean value shows that there is a 9% bias meaning that on average the actual is always 9% above the forecast. It should be noticed as well that there distribution is skewed to the left with higher values meaning that there is a 100% underestimation for certain items. [pic] 2. Use the provided Excel file that contains demand and forecast data for a collection of items. Suppose those are the data LL...

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Risk & Return

standard deviation of the small company returns and large company common returns. 5. The table below provides a probability distribution for the returns on stocks A and B State Probability Return On Stock A Return OnStock B 1 20% 5% 50% 2 30% 10% 30% 3 30% 15% 10% 4 20% 20% -10% a. Given a probability distribution of returns, calculate the expected return, variance, standard deviation of Stock A and Stock B. b. The weighted portfolio of...

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X-Chart and P-Chart

use the calculations you made for question 7: of Homework 3 to support your judgment concerning the normality of the distribution of the data shown in question 2: (also of Homework 3). Give reasons for your answer which might include calculations and/or graphs. Answer: Reasoning/Work: 3: Using normal probability paper, determine (judgment) the normality of the distribution of the following data: 2.566, 2.565, 2.545, 2.551, 2.550, 2.564, 2.542, 2.561, 2.532, 2.565, 2.569, 2.552, 2.558, 2.562...

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Hypothesis Testing: Two-Sample Case for the Mean

analyze statistics from two samples, and the hypothesis and confidence interval would deal with the difference between two population means. The following factors are important in hypothesis testing: 1. probability theory 2. the sampling distribution of the statistic 3. the errors inherent in hypothesis testing and estimation 4. the level of significance and the level of confidence 5. the directional nature of the alternative hypothesis General Procedure 1. State the hypotheses...

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share of stock of Beta Plc is selling for £50. A financial analyst summarises the uncertainty about the rate of return on the stock by specifying three possible scenarios: Business condition End-of-year price Annual dividend High growth £68 £2.5 Normal growth £54 £1.5 No growth £45 £0.5 Assuming all three scenarios are equally likely, calculate: a) the expected holding-period return; b) the variance and standard deviation of the holding-period return; c) the expected return and standard deviation...

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Maths Statistics Paper

Question1: Frequency Distribution. Histograms, Cumulative Frequency and Ogives. 1) a) 799 b) 1000 c) 900+9992 = 949.5 d) Lower Class Boundary=1100-0.5 =1099.5 Upper Class Boundary=1199.5+0.5=1199.5 e) 100 f) 76 g) 62400×100=15.5 h) 600-699, the fourth class has the largest frequency of 76. i)14+46+58400 ×100=29.5% j) 48+22+6400 ×100=19.0% k) 4002=200 200 lie in the fifth class interval 700-799 ∴The median lies in this interval. =l+n2-cff×h =700+200-19468×99 =708.735 l) ...

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