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    Hypothesis Testing

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    Cost Curve Anaylsis

    You have been presented with the following cost data table and asked to fit a statistical cost function. Quantity | 10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 |

    Data analyses

    Attached are data from 2 populations; the first population consists of subjects numbered Combined-POS-1 thri 156 that have been tested for CD4 % LYMPHOCYTES (pos) WBC (X1000/ul) (pos) HB (g/dl) (pos) PLATELETS (x1000/ul) (pos) The second population consists of subjects numbered Combined-NEG-1 There are 642 that have al

    Data Analysis: Oreo and Market Pantry Cookies

    Fort he attached data set perform a z-test for proportion and z-test for both brand names. Find the cutoff value for z, sample proportion, standard error, confidence intervals, one and two-tailed test, critical values, and lower/upper limits.

    Life expectancy hypothesis testing

    On a sample of 50 US married couples, it has been found that on average females live longer (80 years) than males (75 years). a) Using the fact that the corresponding standard deviations are thought to be σ female = 3 and σ male = 4 years respectively, determine if this data indicate that female live longer than males, us

    True Correlation Significant

    Size of Data Set: 100 Regression equation/line: Y=11.20816-0.1098466x Slope is -0.1098466 The y-intecept is 11.20816 Sum of Regression Bar Errors^2=16.6051535247 Sum of YBar Errors=188.830557742 R/correlation coefficient: -0.955020 R^2/coefficient of determination:= 0.912063 X and Y values from the Scatter Plot Points

    Hypothesis Testing and Assessing Levels of Significance

    Perform the following hypothesis tests on the data in spreadsheet HW #1. State the conclusion of the hypothesis tests. The level of significance is 0.05 in each test. 1. The claim that the average Median SAT is over 1200. 2. The claim that the proportion of schools with Expenditures/Student over $50,000 is 0.2. 3. The claim

    Statistics Problem Set: Buena School District Bus

    1. In a market test of a new chocolate raspberry coffee, a poll of 400 people from Dobbs Ferry showed 250 preferred the new coffee. In Irvington, 170 out of 350 people preferred the new coffee. To test the hypothesis that there is no difference in preferences between the two villages, what is the alternate hypothesis? a. H1: p1

    Sampling and Hypothesis Testing Questions

    1. Find the critical value X2 0.99 associated with a X2 curve with 10 degrees of freedom. 2. Find the critical value having an area of 0.05 to its right for an F-curve with 8 numerator degrees of freedom and 15 denominator degrees of freedom. 3. A random sample of 100 adults was recently gathered in order to explore a poss

    Do actively managed funds fail to outperform the overall market?

    It is believed that most actively managed funds fail to outperform the overall market. To empirically test this statement, an analyst has collected the following secondary data to examine whether or not the mean return of an index which represents all the actively managed funds in the market is statistically different from the a

    Statistics Problem: Bacteria in Carpeted Rooms

    Researchers wanted to determine if carpeted rooms contained more bacteria than uncarpeted rooms. To determine the amount of bacteria in a room, researchers pumped the air from the room over a Petri dish at a rate of 1 cubic foot per minute for eight carpeted rooms and eight uncarpeted rooms. Colonies of bacteria were allowed to

    Conducting and Econometrics Analysis

    Please see the attached file. An investigator analysing the relationship between food expenditure, disposable income and prices in the US using annual data over the period 1959-83 computes the following regression log(FOOD) = 4.7377 + 0.1069TIME + 0.3506log(PDI) - 0.5086log(PRICE) (0.6805) (0.0033) (0.0899

    Statistics Problem Set: Confidence Level

    1) For the following sequence: 2,4,7,3,9,4,7,11 find the range, mode, median, mean, IQR, standard deviation, variance and whether it is normally distributed (with explanation) 2) An investor wants to assess at confidence level of 98% if a medicament can improve the marks of students. He notices that for the following daily

    Using Statistics to Analyze a Scenario

    Scenario: You are interested in researching a new ambulance dispatching method. The new method is supposed to be more efficient and uses half the communications personnel of the old method, saving over $300,000 annually. You want to know how the new method compares to the old method in terms of how many minutes it takes ambulanc

    Interpreting the P-Value

    In 280 trials with a professional touch therapist, correct responses to a question were obtained 1223 times. The P-value of 0.979 is obtained when testing the claim that p > 0.5 (the proportion of correct responses is greater than the proportion of 0.5 that would be expected with random chance). What is the value of the sample p

    SPSS Experimental Analysis - Diet of Rats

    See the attached file. A researcher interested in studying the effects of three experimental diets with varying fat contents on the total lipid (fat) level in plasma collected the data in the file FatInDiet.txt. Fifteen male subjects who were within 20 percent of their ideal body weight were grouped into five blocks accor

    Statistics Problem: Patient Illness

    A study was performed on patients with a particular illness. The standard deviation of the weights of 12 patients with the illness was 21.4 kg. A control group of 5 patients without this illness had a standard deviation of the weights of 12.4 kg. Prove if the weights of the patients with this illness are (or are not) more vari

    Statistics Problem: Mean Wait Time

    A bank manager has developed a new system to reduce the time customers spend waiting for teller service during peak hours. The manager hopes that the new system will reduce waiting times from the current 9 to 10 minutes to less than 6 minutes. Suppose that the manager wishes to use 100 waiting times to support the claim that th

    Hypothesis Testing: Milk Volume Example

    Quart cartons of milk should contain at least 32 ounces. A sample of 22 cartons contained the following amounts in ounces. 31.5 32.2 31.9 31.8 31.7 32.1 31.5 31.6 32.4 31.6 31.8 32.2 32.1 32.1 31.6 32.0 31.6 31.7 32.0 31.5 31.9 32.8 a) What set of hypotheses should be tested if we want to demonstrate th

    Standard Deviation, Average Number & P-Value Questions

    1) The club professional at a difficult public course boasts that his course is so tough that the average golfer loses a dozen or more golf balls during a round of golf. A dubious golfer sets out to show that the pro is fibbing. He asks a random sample of 15 golfers who just completed their rounds to report the number of golf

    Baby Birth Weights and Mother Cocaine Use Study

    A random sample of the birth weights of 186 babies has a mean of 3103g and a standard deviation of 696g (based on data from "Cognitive Outcomes of Preschool Children with Prenatal Cocaine Exposure," by Singer et al., Journal of the American Medical Association, Vol. 291, No. 20). These babies were born to mothers who did not us

    Non-Parametric Test on Software Adoption

    Company W is testing a sales software. Their sales force of 500 people is divided into four regions: Northeast, Southeast, Central and West. Each sales person is expected to sell the same amount of products. During the last 3 months, only half of the sales representatives in each region were given the software program to help th

    Statistical Testing - T Tests and Proportions

    1. Do men and women have different beliefs on the ideal number of children in a family? Based on the following GSS2008 Data and the obtained t statistics, what would you conclude? (0.05) Men Women Mean ideal number of children 3.06

    Relative Risk Example Problem

    A multicenter clinical trial involving 17,000 patients suspected of having acute myocardial infarction was conducted. The vascular death rate after 5 weeks was compared in patients receiving aspirin versus those not receiving aspirin, regardless of any other concomitant treatment. The relative risk (RR) for the effect of aspirin

    Distribution Analysis: Statistics for Business Textbook Problems

    6.8 For each of the following rejection regions, sketch the sampling distribution for z and indicate the location of the rejection region. a. z>1.96 b. z>1.645 c. z>2.575 d. z<-1.28 e. z<-1.645 or z>1.645 f. z<-2575 or z>2.575 g. For each of the rejection regions specified in parts a-f, what is the probability that a Typ

    Statistics Variance Problem

    We are interested in determining whether or not the variances of the sales at two music stores (A & B) are equal. A sample of 10 days of sales at store A has a standard deviation of 30, while a sample of 16 days of sales from store B has a standard deviation of 20. 1) What is the value of the Observed test statistic? 2) What

    "T" Value & Developing a Research Question

    Calculate the "t" value for independent groups for the following data using the formula presented in the module. Check the accuracy of your calculations. Using the raw measurement data presented above, determine whether or not there exists a statistically significant difference between the salaries of female and male human resou

    MAD and MSE

    A researcher interviewed 2067 people and asked whether they were the primary decision makers in the household when buying a new car last year. Two hundred seven were men and had bought a new car last year. Sixty-five were women and had bought a new car last year. Eight hundered eleven of the responses were men who deid not buy a

    Statistics and Estimating

    1. Suppose a wildlife service wishes to estimate, with 99% confidence, the mean number of days of hunting per hunter for all licensed hunters in the state during a given season, with a bound on the error of estimation equal to 2 hunting days. How many hunters must be included in the survey? Assume that the data collected in earl