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Hypothesis Testing

Hypothesis testing

Electricity is commonly traded at the California-Oregon border (COB) and Palo Verde (PV) in Arizona. Assume you take a sample of 100 daily electricity market closing prices (in $/megawatthour) from both COB and PV. The following are the summary statistics resulting from your sample: COB PV Average Price $200 $300 Stan

Hypothesis testing of correlation coefficient

The following is a sample Quiz #1 Final 7 34 4 25 2.5 24 8 34 3 20 7.5 34 7.25 42 7 25 5 33 Conduct a hypothesis test to determine if there is a linear relationship (positive correlation) between the two scores or not. Remember to clearly state the null and alternate hypothesis and assume α = .05.

Hypothesis testing

Disney tells you that the average distance between the ears on a Mickey Mouse hat is 5 inches. In a sample of 100 Mickey Mouse hats you find that the average distance between the ears on the hats is 5.2 inches with a standard deviation of 1 inch. Conduct a hypothesis test to determine if the average distance between the ears o

Hypothesis testing

Before I moved to California, I sold my home in Nevada. My realtor told me that the average price of a 2500 square foot home in Nevada was $250,000. I really didn't trust him, so I took a sample of 100 people with 2500 square foot homes in Nevada and found that the average price of a 2500 square foot home was $260,000 with a

Null & Alternative Hypothesis & Five-Step Procedure

The null and alternate hypotheses are: Ho: µ1 = µ2 H1: µ1 >= µ2 A random sample of 15 observations from the first population revealed a sample mean of 350 and a sample standard deviation of 12. A random sample of 17 observations from the second population revealed a sample mean of 342 and a sample standard deviation of 15

Question about Test of mean

Given the following hypotheses: the true mean equals 100 (the null) and the true mean does not equal 100 (the alternate), a random sample of six resulted in the following values: 118, 105, 112, 119, 105, 111. Using = .05, can we conclude the true mean differs from 100? In the process of answering this question: a) state the deci


A TV add, aimed at men, claims that drinking a special weight loss medicine before every meal will result in the loss of at least 5 pounds after two weeks. A skeptical newspaper reporter decides to check if the plan works by having 10 randomly selected women follow the plan for the four week period. The weights for the indivi

Test Ho , mean , two tailed test

Test H0: μ1 - μ2 = 2, HA: μ1 - μ2 > 2, where u1 = 522, u2 = 516, s12 = 28, s22 = 24, n1 = 40, n2 = 30, at α = .01.

Test H0

Test H0: μ = 3.0 versus HA: μ > 3.0 when = 3.44, s = .57, and n = 13 at a significance level of .05. Assume population normality


5. The following data resulted from an experiment to study the effects of leaf removal on the ability of fruit of a certain type to mature: Treatment No of fruits matured No of fruits aborted Control 141 206 Two leaves removed 28

Testing of Hypothesis & Test of Mean

3. Auto Insurance Commissioner Auto insurance premiums in Massachusetts depend on the age of the driver and the driver's record but are not supposed to depend on gender. The state insurance commissioner wants to investigate whether there is any difference in the average premium that company A charges males and the average pre

Statistics Problem

The Atlanta Convention & Visitors Bureau just released a report on the percentage of available hotel rooms in Fulton County that were rented (occupied) in 2003. Looking over the report you note that room occupancy in March of 2003 was 77.6% (total rooms available is 14,800) and in December of 2003 it was 55.5% (of the 14,600 av

Test of hypothesis for proportions

Suppose prior elections in Louisiana indicated it is necessary for a candidate for governor to receive at least 80 percent of the vote in the northern part of the state to be elected. The incumbent governor is interested in assessing his chances of returning to office and conducts a survey of 2,000 registered voters residing i

I need help matching statistical symbols and definitions

I need your HELP with the matching of STATISTICAL SYMBOLS & DEFINITIONS DEFINITION 1.The average of the squared deviation scores from a distribution menas. 2. Midpoint in the distribution of numbers. 3. It has to do with the accuracy and precision of a measurement procedure. 4.Examines if an observed causal relationship

Statistics Variable Identification

A researcher has a data-set that includes the following variables measured on 50 small children. Given these variables: a) gender (male / female) b) age (continuous variable measured in months; ranges from 36 months to 72 months) c) preschool or daycare attendance (yes / no) d) height (continuous variable measured in

Hypothesis test..

An office equipment company advertises that it will deliver equipment within 15 days of purchase. A sample of 49 past deliveries is taken to test whether company's advertisement is valid. The delivery time for this sample was 16.2 days with a sample standard deviation of 5.6 days. Which of the following is correct * What is t

Research and Evaluation

1) A normal tomato will gain an average of 2 ounces per week during the growing season. A sample of 100 tomatoes is given a special hormone to increase their growth. The average weight gain of tomatoes in the sample was 3 ounces with a standard deviation of 1 ounce. Conduct a hypothesis test to determine if the hormone incre

Hypothesis Testing for the Proportion Parameter

Hypothesis Testing for the Proportion Parameter 1.) It is thought that the front cover and the nature of the first question on mail surveys influence the response rate. The article "The Impact of cover Design and First Question on Response Rates for a Mail Survey of Skydivers" (Leisure Science, 1991) tested this theory by exp

Testing of hypothesis of means

To test if the population mean is greater than 20 . We use z-test to test if the population mean is > 20 . We also use z-test to test if there is significant difference between means. See attached file for full problem description.

Descriptive Statistics of Hispanic Aid Support

(See attached file for full problem description and proper table representation) 1) Descriptive statistics: Please interpret this data a provide a description of the data represents. As you compare the means visually, what is your first impression about the difference in these means? Hispanic Women Hispanic Men Non- Hispa

Regression analysis: education and salary

Use the dataset "Employee data" (attached). Perform a regression that studies the impact of years of education on current salary. 1.(a) How may we interpret the coefficient for education? (b) Is the coefficient for education significant at the 5% level? (C ) What hypotheses are being tested by the t-statistic? (d) What

Room Size and BTUs

Based on the question and the bogus raw data, provide a complete analysis. Be sure to include statdisk or excel: Does the room size play an important factor in choosing the correct BTU's? A general rule is that 5,000 to 6,000 Btu/hrs. models cool rooms 100 to 300 square feet; 7,000 to 8,200 Btu/hr. models cool rooms 250 to 55

Statistics Concepts and Calculations

16-22. The following sample data were obtained from three populations where the variances were not equal, and you wish to compare the populations. Sample 1 Sample 2 Sample 3 21 15 38 29 17 40 35 22 44 45 27 51 56 31 53 71 1. State the null hypothesis. 2. Using the .01 level of risk, state the decision rule. 3. C

Significance testing in 5 different situations

1. Suppose you want to test the claim that the population mean(u) is < or equal to 25.6. Given a sample size of n=44 and a level of significance of 0.05, when should you reject the null hypothesis? 2. Given the null hypothesis: population mean = 25 and the alternative hypothesis population mean not equal to 25, and P=0.041

One-Tailed Tests for Population Standard Deviation of Mean Income of Teachers

Past records suggest that the mean annual income, u1, of teachers in state of Utah is greater than or equal to the mean annual income, u2, of teachers in Oregon. In a current study, a random sample of 10 teachers from Utah and an independent random sample of 10 teachers from Oregon have been asked to report their mean annual inc

6 Hypothesis Testing Questions

Problem 14.3 The marketing manager of a large supermarket chain would like to determine the effect of shelf space on the sales of pet food. A random sample of 12 equal-sized stores is selected, with the following results: (see attachment for clearer tables) Store Shelf Space X (Feet) Weekly Sales Y (Hundreds of Dollars

Statistics, Research and Evaluation

1. Determine what would happen to your critical value (Z) if you were to change the level of significance (a) from .05 to .1 in a two tailed hypothesis test. 2. Why would the critical value change in the way you predict? 3. What does this suggest about the trade offs between Type 1 and Type II errors? Please give s

Hypothesis Test: Two-tailed Test of Difference Between Means

According to the historical data, the life expectancy in Argentina is equal to the life expectancy in Bolivia. A new study has been made to see whether this has changed. Records of 295 individuals from Argentina who died recently are selected at random. The 295 individuals lived an average of 74.8 years with a standard deviat