"Sample Size" Essays and Research Papers

Sample Size

HW #4 Name: 1. What is the difference between [pic] and[pic]? Between s and[pic]? (10 points) 2. Explain the difference between [pic] and [pic] and between [pic] and[pic]? (10 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...

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Multiple Sample Hypothesis

Running head: MULTIPLE SAMPLE HYPOTHESIS TESTING Multiple Sample Hypothesis Testing RES342: Research 11 June 14, 2010 Multiple Sample Hypothesis Testing The purpose of this paper is to create a hypothesis based on two-sample tests. Two-sample tests compare two sample estimates with each other, whereas one-sample tests compare a sample estimate with a non-sample benchmark (Doane & Seward, 2007). The learning team has chosen to create a hypothesis testing using the wages and wage earners...

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Estimating Population Size Using Mark and Recapture Method

Practical 16: estimating Population Size Using Mark and Recapture Method Raw and Processed Data Table 1: Uncertainties of apparatus used in the experiment. Apparatus | Uncertainties | Stopwatch | ±0.01s | Table 2: Formulae and sample calculations involved in processing data in the experiment. Calculations | Formula | Sample Calculation | Mean ( x ) | x = 1n i=1naiWhere, 1. n refers to the total number of values. 2. ∑ refers to the addition of all values starting with the first value...

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Sample of Demand and Supply Analysis

Results of Survey ( Bakeries and Pastry Shops) Sample size: 12 Question # Answers Number of Respondents 1 . How often do you order sacks of flour? Daily 5 Weekly 7 Monthly 0 2. How many sacks of flour do you order per delivery? 2 sacks 2 3 sacks 2 4 sacks 7 5 to 10 sacks 1 3. How many sacks do you consume per delivery? 2 sacks 2 3 sacks 2 4 sacks 7 5 to 10 sacks 1 4. Are there instances that you ran out of sacks of flour? Yes 10 No 2 5. How often does...

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Two Sample Tes

A sample of 65 observations is selected from one population with a population standard deviation of 0.75. The sample mean is 2.67. A sample of 50 observations is selected from a second population with a population standard deviation of 0.66. The sample mean is 2.59. Conduct the following test of hypothesis using the .08 significance level. |   H0: µ1 ≤ µ2 | H1: µ1 > µ2 |   (a) | Is this a one-tailed or a two-tailed test? |     This a one -tailed test. |   (b) | State the decision...

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Hypothesis Testing: Two-Sample Case for the Mean

Hypothesis Testing: Two-Sample Case for the Mean Many cases in the social sciences involve a hypothesis about the difference between two groups (i.e. men and women, control and experiment). We 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...

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One Sample Hypothesis Testing

One Sample Hypothesis Testing I am working on a problem in Excel but I am having trouble with my T- Distribution. I am using the TDIST function but have been unsucessful in my calculations. Here is the case scenario: One hundred customers at the Mall of Elbonia (MoE) were given a brief interview as they concluded their shopping trips. Examine the resulting data in the Mall of Elbonia Interview Results file. For each customer (by row), the spreadsheet contains data on: The customer's...

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Calculating Sample Size

Calculating Sample Size Types of Samples   Subjective or Convenience Sample  - Has some possibility of bias - Cannot usually say it is representative - Selection made by ease of collection Simple Random Sample  - No subjective bias - Equal chance of selection; e.g., select the fifth chart seen on every third day - Can usually be backed to say it is representative Systematic Sample  - Is a random sample - Equal chance of selection due to methodology; e.g., computer-generated list of ...

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Calculating the Sample Size

Transportation Survey Sample Calculation The confidence interval (also called margin of error) is the plus-or-minus figure usually reported in newspaper or television opinion poll results. For example, if you use a confidence interval of 4 and 47% percent of your sample picks an answer you can be "sure" that if you had asked the question of the entire relevant population between 43% (47-4) and 51% (47+4) would have picked that answer. The confidence level tells you how sure you can be. It is...

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Qnt561 One and Two Samples Sets Week 5

One- and Two-Sample Tests of Hypothesis, Variance, and Chi-squared Analysis Problem Sets University of Phoenix Applied Business Research and Statistics QNT 561 August 5, 2011 Chapter 10 Exercise Question 31: A new weight-watching company, Weight Reducers International, advertises that those who join will lose, on the average, 10 pounds the first two weeks with a standard deviation of 2.8 pounds. A random sample of 50 people who joined the new weight reduction program revealed the mean...

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APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES

APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES M.C. MENDOZA1 1NATIONAL INSTITUTE OF MOLECULAR BIOLOGY & BIOTECHNOLOGY, COLLEGE OF SCIENCE UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY 1101, PHILIPPINES DATE SUBMITTED: 21 NOVEMBER 2013 DATE PERFORMED: 14 NOVEMBER 2013 ABSTRACT Accuracy and precision are critical concepts to the performance of a laboratory to produce sound analytical results (Singer, 2001). LOLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL ...

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Application of Statistical Concepts in the Determination of Weight Variation in Samples

Application of statistical concepts in the determination of weight variation in samples G.E. Institute of Biology, College of Science University of the Philippines, Diliman, Quezon City, Philippines Date Submitted: April 23, 2013 ABSTRACT Statistics is a mathematical science dealing with the collection, organization, analysis, interpretation, and presentation of data. It provides a more accurate way of expressing data rather than mere observation. This experiment used the different statistical...

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Omis 41 Statistics Study Guide

What is statistics? Making an inference about a population from a sample. • What is the logic that allows you to be 95% confident that the confidence interval contains the population parameter? We know from the CLT that sample means are normally distributed around the real population mean (). Any time you have a sample mean within E (margin of error) of then the confidence interval will contain . Since 95% of the sample means are within E of then 95% of the confidence interval constructed...

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Buisness Statatis

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 of sample means around the population mean. It is known as the standard error...

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Evaluating the Limitations of Market Research

Reliability is vital when trying to find out information about large target populations. To avoid poor reliability, the sample chosen to participate in the research should be representative of the whole target population. The correct target sample must be established so that reliability is not a limitation of the research. To improve poor reliability due to target sample, a list of the target population could be created and then have a number of people selected from that list. It is important...

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Testing Statistical Significance

Testing statistical significance is an excellent way to identify probably relevance between a total data set mean/sigma and a smaller sample data set mean/sigma, otherwise known as a population mean/sigma and sample data set mean/sigma. This classification of testing is also very useful in proving probable relevance between data samples. Although testing statistical significance is not a 100% fool proof, if testing to the 95% probability on two data sets the statistical probability is .25% chance...

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Turkish people and diabetes

from the health system (Makowski, Anna Christin and Christopher Kofahl 2014). The study took the sample in Hamburg by interviewing the Turkish people, face to face. The sample is almost evenly distributed by gender and the people have been chosen in two ways. The first method was by the doctor’s offices and the second one by word of mouth. The research stated that in this way they took a more random sample. The final number from 294 possible candidates, 108 participants were part of the program. The...

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Project and Quality Management Questions

PROBLEMS P1. After a number of complaints about its directory assistance, a telephone company examined samples of calls to determine the frequency of wrong numbers given to callers. Each sample consisted of 100 calls. The results to date are shown below. Analyze the data using an appropriate control chart with a 5% risk of Type I error. Is the process stable (i.e., in control) based on the limits? Sample # of errors 1 5 2 3 3 5 4 7 5 4 6 6 7 8 8 4 9 5 10 9 11 3 12 4 13 5 14 6 15 6 16 7...

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Alu Lab

environmental conditions are met, allele and genotype frequencies in a population will remain constant between generations. Those conditions include the absence of mutation, the absence of migration from other populations, the population is infinite in size, the equal survival and reproduction of all genotypes in the population, and random mating between the individuals of the population. Because natural populations never fully meet all five requirements simultaneously, the Hardy-Weinberg principle serves...

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Ethical Behavior of Business Students at Bayview University

proportion of all students: Sample size=90, sample proportion=0.53, level significance is 0.05. Standard Errors=^P (1-P)/n=0.0511 Z-socre=1.9600 Width of the confidence interval=z*se=0.1002 Lower Limit of the confidence interval=p-width=0.4298 Upper Limit of the confidence interval=p+width=0.6302 The confidence interval for the proportion of all students is 0.43 to 0.63. (2) 95% confidence intervals for the proportion of male students: Sample size=47, sample proportion=0.57, level significance...

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Statistical Inference and Interval Estimate

proportion. b) Is finding an interval estimate an example of inferential or descriptive statistics? Explain. It is an interval estimate is an example of inferential statistics, as an estimate of the value of the population parameter is made based on sample statistics. c) An interval estimate (23.8, 30.6) is determined for the mean age of NSCC students. Identify the point estimate and the margin of error of the interval estimate. The point estimate=27.2 and the margin of error=3.4 d) The proportion...

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Quantitative Skills Assessment Questions

SECTION A (You should attempt all 10 questions) A1. The sample mean is an unbiased estimator for the population mean. This means: (A) The sample mean always equals the population mean. (B) The average sample mean, over all possible samples, equals the population mean. (C) The sample mean is always very close to the population mean. (D) The sample mean will only vary a little from the population mean. A2. The central limit theorem tells us that the sampling distribution of the mean is approximately...

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Confident Interval

1. According to the National Center for Health Statistics (2004), 22.4% of adults are smokers. A random sample of 300 adults is obtained. (a) Describe the sampling distribution of phat, the sample proportion of adults who smoke. (b) In a random sample of 300 adults, what is the probability that at least 50 are smokers? (c) Would it be unusual if a random sample of 300 adults results in 18% or less being smokers? Explain your answer. 2. A machine at K&A Tube & Manufacturing...

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Procedure for Hypothesis Testing

set at 0.05. A random check of 172 unpaid balances revealed the sample mean is $407 and the standard deviation of the sample is $38. Should the credit manager conclude that the population mean is greater than $400? Question 2 A machine is set to fill a specially designed bottle with 9.0 grams of vitamins. It is claimed that the mean is less than 9.0 grams. The hypothesis is to be tested at the 0.01 level. A sample revealed these weights (in grams): 8.7 | 8.5 | 9.0 | 9.2...

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Process Improvement Plan Paper

No Yes Improvements in any process start Statistical process control, which is the random testing of a sample of output from the process to determine whether the process is producing items within a preselected range (Chase, Jacobs, & Aquilano, 2006). These samples may be either fit or unfit for example taking random samples from a batch of newly made Motorola I Pad. Testing may discover that some will work accordingly whereas other will not power on. Companies...

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Statistics Chapter 7 Homework

margin of error? –What was the sample size? -What sampling design was used? –What was the response rate? –What was the frame that was used? -Who paid for the survey? –From the sample that was selected, what was the population? Ch. 7 Pr. 17 For each of the following three populations, indicate what the sampling distribution for samples of 25 would consist of: a. Travel expense vouchers for a university in an academic year. -The sampling distribution of a sample means is the distribution of means...

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Sieve Analysis Test Lab Report

occupied by aggregates. One of the physical properties of aggregate that influence the property of concrete is the grading of aggregate. The grading of aggregate defines the proportions of particles of different size in the aggregate. The grading of fine (size < 5 mm) and coarse (size > 5 mm) aggregates are generally required to be within the limits specified in BS 882: 1992. OBJECTIVE The objective of this experiment is to obtain the grading curve for both fine and coarse aggregate....

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QMB 3200 Summer Final prep

percentage of the individual population measurements, while the confidence interval is meant to contain only one number—the population mean. Starting chapter 7 and the rest of the chapter you will be using statistical samples that fall into the following two categories: Small size (n) sample where n 32 when .05, we should reject H0. True False = 36, s = 1.6, and n = 30 at  = In the [H0 : µ ≤ µ0 vs HA : µ > µ0 ] Hypothesis scenario. What value (or values) of alpha (α) would we reject H0 for...

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APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES

APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES D. E. BIACORA DEPARTMENT OF MINING, METALLURGICAL AND MATERIALS ENGINEERING COLLEGE OF ENGINEERING, UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY, PHILIPPINES DATE PERFORMED: 19 November 2013 INTRODUCTION Analytical chemistry involves the separation, identification and determination of amounts of components in a particular sample. Accuracy and precision are important in data acquisition to be able...

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Statistics Exam

probability is approximately 1.000. 1 4. A researcher is interested in whether the location of population 1 differs from that of population 2. She has gathered two independent samples. She has 3 observations from population 1: 12, 15, 9. Moreover, she has 4 observations from population 2: 10, 14, 13, 11. Using these samples, can the researcher conclude at a significance level of 0.05 that the two population locations differ? a. The relevant test statistic lies in the rejection region; the researcher...

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Sqc - Statistical Quality Control

statistical techniques to determine whether a process is functioning as desired II. Acceptance Sampling: - the application of statistical techniques to determine whether a population of items should be accepted or rejected based on inspection of a sample of those items. Quality Measurement: Attributes vs Variables Attributes: Characteristics that are measured as either "acceptable" or "not acceptable", thus have only discrete, binary, or integer values. Variables: Characteristics that are...

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Capture Mare Recapture Technique

Maria Pamela S. Tadeje, Sheena Jean C. ABSTRACT By the use of CMR technique, this activity aims to estimate a population size in a given area in a simple manner. In this method in which a sample is captured, marked, and released and the proportion of marked individuals to unmarked in a later sample is used to estimate total populations. The activity was conducted just in inside our classroom at s14 CNSM building. After this activity we are able to appreciate...

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Nice

application, a client game quality associates a sample of 800 observations taken during a time in which that client's process was operating satisfactorily. The sample standard deviation for there data was .21 ; hence, with so much data, the population standard deviation was assumed to be .21. Quality associates then suggested that random samples of size 30 be taken periodically to monitor the process on an ongoing basis. BY analyzing the new samples, the client could quickly learn whether the process...

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Pilgrim Sampling

obtain a random sample of 31,634 customers on the following variables – Profitability (in $, for the most recent completed year, i.e. 2006), whether or not the customer uses the online banking channel, customer tenure, age and income where available, as well as the customer’s residential area. Descriptive statistics for Profits indicates that the average profit per customer is $111.50 with a standard deviation of $272.84. a. Is Joe justified in assuming that this is a “large” sample? (see slide...

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IET STATS

deviation of the sample are computed. Based on these sample results, the production control manager determines whether the filling machine needs to be readjusted or whether it remains all right to operate. Use α = 0.05. a. Establish the appropriate null and alternative hypotheses to be tested for boxes that are supposed to have an average of 24 ounces. Ho: u= 24 OZ Ha: u≠ 24 OZ b. At the end of a particular shift during which the machine was filling 24-ounce boxes of Mini-Oats, the sample mean of 16...

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Acc 403 Week 8 Homework

approved price list. | Test of Control | Classification | Examine a sample of sales transactions to determine if each one is correctly classified in the sales journal. | Substantive Test of Transactions | Completeness, Accuracy, Timing, Posting, and summarization | N/A | Substantive Test of Transactions | Occurrence, Completeness, Accuracy, and Timing | N/A | Test of Control | Accuracy | Recalculate cash discounts for the sample of remittances to determine whether each one was consistent with...

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Dq Questions

only with those two individuals), or (2) taking a sample of the population from which to make generalizations (Leedy & Ormrod, 2010.)  The researcher must never assume that qualitative research studies always involve the use of small samples. In fact, qualitative research can utilize large samples, as in the case of program evaluation research. Leedy & Ormrod (2010) mentioned that the association of qualitative data analyses with small samples is to ignore the growing body of literature in the...

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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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Tutorial 4

random sample of 40 bricks from a day's output had a mean weight of 4.07lb. (i) Find a 99% confidence interval for the mean weight of all bricks produced on that day. (ii) Estimate the smallest sample size required if the error in estimating the population mean weight of all bricks is to be within  0.03lb with 95% confidence. 2. A house cleaning service claims that they can clean a four bedroom house in less than 2 hours. A sample of n = 16 houses is taken and the sample mean is...

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Concept of ANOVA

of multiple levels of two factors and we have multiple observations at each level. Grand Mean The grand mean of a set of samples is the total of all the data values divided by the sample size. It turns out that all that is necessary to find perform a one-way analysis of variance are the number of samples, the sample means, the sample variances, and the sample sizes. Total Variation The total variation is comprised the sum of the squares of the differences of each mean with the grand mean...

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Stats

enrolled in a university statistics unit were given the choice of three tutorial methods to support the lectures in the unit. These were: on-line tutorials, self-paced tutorials and tutorials conducted by a tutor. At the end of the semester a random sample of students was selected from each of the three tutorial methods and their final results (%) compared. Use the output provided below to answer the following questions: a) Which of the three methods gave the best results overall? Explain your...

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Quality Associates, Inc.

about sampling and statistical procedures that can be used to control their manufacturing process. Their client has offered samples to be analyzed, so they can quickly learn whether the process is operating satisfactorily or corrective actions needs to be taken. The numbers given in the case were as follows: assumed population standard deviation is equal to .21, sample size is equal to 30 and the test value of the mean was 12. They also stated the two hypotheses to be tested: the null hypothesis...

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Assignment 1

10.89 1.99 (32.82, 39.57) C18 30 40.15 10.30 1.88 (36.96, 43.35) C19 30 37.34 9.08 1.66 (34.53, 40.16) C20 30 39.46 10.65 1.94 (36.16, 42.77) C21 30 34.71 9.21 1.68 (31.85, 37.57) d) 1 Sample T-Test for Variable C2 n= 30 df= 29 = 36.91 SE= 1.92 α= 1-CC = 1.0.90 = 0.1 e) Apply binomial theorem for x= 16, 17,18,19,20 p=0.9 q=0.1 n=20 16 Interval 17 Interval 18 Interval 19 Interval 20 Interval ...

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Bus Template

paragraph (use the tab key). The introduction should be short (2-3 sentences). The margins, font size, spacing, and font type (italics or plain) are set in APA format. While you may change the names of the headings and subheadings, do not change the font or style of font. Part 1: Survey Analysis: Entertainment Describe an entertainment poll or survey. Analyze the number of people who participated in the sample compared to the number in the population. (Be sure to cite the article which must be from ProQuest...

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Milk Production in India

1. SOCIO-ECONOMIC CONDITIONS OF MILK SOCIETY FARMERS IN AVANOOR PANCHAYATH. Avanoor is one of the village in puzhakkal taluk, thrissur district, Kerala state: panchayath situated with18.25 square kilometer total land size. Total population in Avanoor Panchayath is 20040. Among the total population 9729 males and 10311 females. Avanoor bounded with Mundathicode and velur panchayath in the North, Kaiparambu panchayath in the west, Adatt and Kolazhy panchayaths in the south, Mulankunnathkavu panchayath...

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Important Statistics Formulas

these formulas assume simple random sampling. * Sample mean = x = ( Σ xi ) / n * Sample standard deviation = s = sqrt [ Σ ( xi - x )2 / ( n - 1 ) ] * Sample variance = s2 = Σ ( xi - x )2 / ( n - 1 ) * Variance of sample proportion = sp2 = pq / (n - 1) * Pooled sample proportion = p = (p1 * n1 + p2 * n2) / (n1 + n2) * Pooled sample standard deviation = sp = sqrt [ (n1 - 1) * s12 + (n2 - 1) * s22 ] / (n1 + n2 - 2) ] * Sample correlation coefficient = r = [ 1 / (n - 1) ] * Σ...

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Statistics Project

Sugar Content of Popular Cereals Purpose: Analyze and compare sugar content of popular cereals with the same serving size. Cereal is a staple in my home, but chosen for different reasons. Cereals that are popular with kids are starting to advertise more fiber and grains, which capture a parent’s eye. Is eating a blander colored cereal really more healthy than a vibrant colored one? | | | | | | | | | | | | | | | | | | | | | | Category(X): | Cheerios | Crispix...

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Math 533 Part B

a = .05 as the significance level, and observing the sample size of n < 30 which tells me I need to use a Z-Test to find the mean of this test and the hypothesis. As the alternative hypothesis is Ha: u < $45,000, the given test is a one-tailed Z-Test. The critical value for the significance level, α=0.05 for a one-tailed z-test is -1.645. Decision Rule: We must reject the hypothesis if z >1.645 Test Statistics from Minitab: One-Sample Z: Income ($1000) Test of mean = 45, < 45 The proposed...

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Week 4 Assignment 4.1

used for a hypothesis test of the claim that the proportions of male smokers and female smokers are equal. First, the sample is not random, it is a convenience sample and therefore cannot be trusted. Second, np҄ = x = 4 &lt; 5, therefore the normal distribution cannot be used to approximate the binomial distribution. Given a simple random sample of men and a simple random sample of women, we want to use a 0.05 significance level to test the claim that the percentage of men who smoke is equal to...

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Wentworth Medical Center

the relationship between geographic location and depression. A sample of 60 individuals, all in reasonably good health, was selected; 20 were residents of Florida, 20 were residents of New York, and 20 were residents of North Carolina. From the data collected we could know that the higher test scores indicate higher levels of depression. The descriptive statistics of the data collected are as following: GROUPS SIZE SUM MEAN SAMPLE VARIANCE FLORIDA 20 88.50 4.42 3.81 NEW YORK 20 131.53 6.58 3...

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Practice Midterm Exam (Statistics)

package weight is above 16 ounces. George Williams, quality control manager, advises him to examine a random sample of 25 packages of cereal. From his past experience, George knew that the weight of the cereal packages follows a normal distribution with standard deviation 0.4 ounce. At the significance level α =.05, (1) What is the decision rule (rejection region) in terms of the sample mean [pic]? Please derive the general formula using the concept of Type I error rate. (2) What is the power...

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M&M Project

histograms and identifying their shape such as bell, constructing confidence intervals for proportions and hypothesis testing of the samples. Each section of the M&M® project will demonstrate a lesson that was learned by applying the knowledge from the class to each separate part of the M&M project itself. The paper will conclude by discussing reasons why the results of the samples may have been different than anticipated. Introduction: Purpose of the Report The main purpose of the M&M®...

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mcfc08 he1

more than 45 minutes. (b) Mr. Jones spends more time traveling than in the library. 6. It is estimated that of the population of England watched last year’s Cup Final on television. If random samples of 100 people are interviewed, (a) calculate the mean and variance of the number of people from these samples who watched the Cup Final on television. (b) calculate the probability that more than 30 people watched the Cup Final on television. 7. Four hundred pupils sit a test which consists of 80...

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Normal Distribution and Multiple Vitamin

distribution of the sample mean age is incorrect? a) The mean of the sampling distribution is equal to 23 years. b) The standard deviation of the sampling distribution is equal to 3 years. c) The shape of the sampling distribution is approximately normal. d) The standard error of the sampling distribution is equal to 0.3 years. ANSWER: b 3. Why is the Central Limit Theorem so important to the study of sampling distributions? a) It allows us to disregard the size of the sample selected when the population...

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Math533 Poject B 1

Alternative Hypotheiss: The average annual income was less than $50,000 Ha:u <50,000 Test Statistic: Rejection Region: For a=.05, one sided Z-test, Z<-1.645 Assumptions: -Sample is randomly selected -Sample is large (z ≥ 30) -Central Limit Theorem applies, test statistic will be approximately normal One-Sample Z Test of mu = 50 vs < 50 (in $1,000’s) The assumed standard deviation = 14.55 95% Upper N Mean SE Mean Bound Z P 95% CI 50 43.48 ...

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Application 1 & 2

Service Representatives 1. The reliability for both the clerical and the work samples are favorable. We see in the Clerical Test that the co-efficient alpha (at .85 and .86) and the test-retest (.92) are both high so we have an acceptable degree of reliability for the test. For the Work Sample (T) & Work Sample (C) we find the inter-rater agreements to be high at with Work Sample (T) being T1=88% and T2=79% and Work Sample (C) T1=80% and T2=82%, both above the 75% normal requirement for a reliable...

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Biostatistics

critical method * X= 60, level of significance= 0.05 * Reject null hypothesis GENETICS | | | | Data | Null Hypothesis = | 0.79 | Level of Significance | 0.05 | Population Standard Deviation | 20 | Sample Size | 100 | Sample Mean | 60 | | | Intermediate Calculations | Standard Error of the Mean | 2 | Z Test Statistic | 29.605 | | | Two-Tail Test |   | Lower Critical Value | -1.959963985 | Upper Critical Value | 1.959963985 | p-Value |...

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Something

hybrid of the two. 2 The coffee studies Joe viewed were not entirely relevant. Most have glaring issues with their methodology and reliability of the data collected. The issue with the first two studies is the sample size; the sample size being one. This is too small to be a sample, and as such are merely opinions of individuals. One thing that might be slightly useful is that the first study did include prices of coffee, albeit plain black. The savings of a few cents were not enough make the...

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Unit 6 Assignment

equal.   b. Samples and Populations: Given your research question and hypothesis above, what would your population of interest be? Describe your population. My population of interest is: men and women between the ages of 22 and 30 that have taken the MCAT one time. Describe the population – what does it contain? The population contains men and women ages 22 to 30. To test your research hypothesis, describe the sample you might collect, including sampling method and size. How big is...

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HW 1 STAT 252

> $520 B) C) Assumptions: 1) Simple Random Sample (SRS): We can assume that the sample was selected by random. 2) 10% Assumption: We can assume that the sample size (n=27) is less than 10% of the population. 3) Nearly Normal: n = 27, which is less than n=30. We need to look at the boxplot and histogram to determine if the sample is normal. The diagram shows that the sample data is skewed to the left, with an outlier at 200. The sample is not normal because the diagram is not unimodal...

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