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Hypothesis Testing

Test of hypothesis, p value, confidence interval, linear regression

1. The wages for middle managers in a certain industry are thought to be no more than $45,000.00. A wage survey of 30 managers has a mean income of $46,260.00. Test the hypothesis at a 1% significance level. Does it appear that the average annual income is greater than $45,000.00? The population standard deviation is assumed

A question about null hypothesis is included.

In a study in which null hypothesis has been rejected, we should be aware of the possibility of ________ alternative hypotheses, Type II Errors, change due to new observations, all are correct This question is posed.

Multiple choice questions on testing of hypothesis

1.The power of a test is measured by its capability of a. rejecting a null hypothesis that is true. b. not rejecting a null hypothesis that is true. c. rejecting a null hypothesis that is false. d. not rejecting a null hypothesis that is false. 2. If an economist wishes to determine whethe

Statistical Analysis - Background Music

A researcher had the idea that background music might enhance performance on a math test and that the effect of music might depend on whether an individual is a music lover or not. She selected 50 music lovers and 50 control participants who did not listen to music on a regular basis. Half of the participants from each group t

Multinomial, Negative Binomials and Hypothesis Testing

I have several questions I'm stuck on: 1. A production line produces good articles with probability .7, average ones with probability of .2, and defective ones with probability .1. Ten articles are selected. a) What is the probability of 8 good ones and 1 defective? b) What is the probability that there

Statistic Problems and Harassment

Employers sometimes seem to prefer executives who appear physically fit...Here are the data...c) You should also hesitate to conclude that increasing fitness causes an increase in ego strength. Explain why?

Null Hypothesis Sample Deviation Effects

2)Your company has recently changed suppliers of a certain raw material in an effort to reduce the number of defective units being produced at your plant. During the past year, the sampling has indicated a daily mean of 21.2 defective units. After testing the new suppliers raw materials for 30 days, it was found that the mean

Null Hypothesis Level of Significance

1)According to company figures, the age of a first time customer is normally distributed with an average age of 29.8 years and a standard deviation of 4.5 years. The marketing department has designed a new advertising strategy and wants to determine if this has had any impact on the average viewing age. Since the new ad campai

Computing the P-Value: The Iowa Department of Highways

An official of the Iowa Department of Highways wants to compare the useful life, in months, of two brands of paint used for striping roads. The mean number of months Cooper Paint lasted was 36.2 with a standard deviation of 1.114 months. The official review 35 road stripes. For King Paint, the mean number of months was 37.0 w

One tailed test of hypothesis: difference between means

To evaluate the relative merits of two prosthetic devices designed to facilitate manual dexterity, an occupational therapist assigned 21 patients with identical handicaps to wear one or the other of two devices while performing a certain task. 11 patients wore device A and 10 wore device B. The researcher recorded the time each

Hypothesis Testing and Power Functions

5.5.8 Let us say the life of a tire in miles, say X, is normally distributed with mean 0 and standard deviation 5000. Past experience indicates that 0=30,000. The manufacturer claims that the tires made by a new process have mean 0 >30,000. It is possible that 0=35,000. check his claim by testing H0: 0=30,000 against H1: 0 >

Statistics for Observed Significant Results

1. Given the following N's (where N is the number of pairs of observations) and obtained r's, indicate whether the result is significant at the .05 level: (a) N = 100, r = .22 (b) N = 100, r = .60 (c) N = 9, r = -.70 (d) N = 36, r = .23 (e) N = 100, r = -.19 2. Given the following data, what are the correlation and the

Hypothesis Testing: Power functions

We say a critical region C is of size  if = max P{(X1,....,Xn)  C], 0 We define the power function of a critical region to be c()= P[(X1,...Xn) C], 1 1)Let X have a pdf of the from f(x; )= x^(&#615

Survey Responses

Using the large database of survey responses (this is your sample), you will begin testing hypotheses. Complete the following: 5. We will call a "desk body" a person whose intrinsic job satisfaction level is higher than their extrinsic job satisfaction level. We will call a "social body" a person whose extrinsic job sati


In a 1999 survey, 55 of 100 randomly selected companies reported Internet sales. In a 2000 survey, 63 of 100 randomly selected companies reported Internet sales. For the alternative hypothesis HA: π1 ≠ π2 at level of significance 0.10, what is the value for the unknown population proportion, the critical values,


Suppose the state department of real estate conducts a study of the number of first-time applicants who are successful in passing the state certification examination for real estate salespeople on their first attempt... What is the sample proportion of real estate employees who passed the exam on their first attempt? a. 0.26

Null hypothesis testing

3b) In this diagnostic, I will set the test a restricted model eliminating the 'smoking', setting this parameter to zero to test against the full regression model. (?) 3c)In this diagnostic, I will set the test a restricted model eliminating the as.factor(race)*ht, setting this parameter to zero to test against the full regre

Hypothesis that women smile more

Louise was conducting a study to test her hypothesis that women smile more often than her male participants. Her hypothesis will probably be confirmed due to a. Social desirability b. Reactivity c. Experimentor expectancies d. Habituation I think that the answer is c. Am I on the right track?

Significance Level

10.42 Nitrogen and Seagrass. The seagrass Thalassia testudinum is an integral part of the Texas coastal ecosystem. Essential to the growth of T. testudinum is ammonium. Researchers Kun-Seop Lee and Kenneth H. Dunton of the Marine Science Institute of the University of Texas at Austin noticed that the seagrass beds in Corpus C

Test of independence

This is a generic question: A researcher who uses a "test of independence" to analyze his data in using a(n) a. Two way chi-squared test b. Independent-samples-test c. Dependent-samples t-test d. Meta-analysis

Ten true-false questions about the sample mean and sample variance calculated on a sample from a normal distribution and using the mean and standard deviaton when testing hypotheses.

Please use words to describe the solution process. In the statements that follow, X is a normally distributed random variable with mean [symbol1] and variance [symbol2]. Furthermore, X1,...,Xn are independent random variables wit the same distribution as X ... Please see attachment for complete question and proper citation

Independent & Dependent variables

Choose a hypothesis and operationally define a variable in the hypothesis. Your operational definition will consist of measures at the self-report, behavioral, and physiological levels as well as a manipulation of the variable. Your operational definition should be written in such a way that you could measure and manipulate it


10.48 Nitrogen and Seagrass. Refer to Exercise 10.42. a. Determine a 98% confidence interval for the difference, M1-M2, between the mean sediment ammonium concentrations in CCB and LLM.

Inferences Two Samples

See attachment below. Please show how all work was obtained. A) State the null and alternate hypothesis. B) Determine the rejection region. For example "if , then reject ". C) Determine the Test Statistic. D) Conclude either "Reject " or "Do not reject " based on your analysis and answer the question. E) Determine the

Inferences from Two Samples

A) State the null and alternate hypothesis. B) Determine the rejection region. For example "if , then reject ". C) Determine the Test Statistic. D) Conclude either "Reject " or "Do not reject " based on your analysis and answer the question. E) Determine the p value of the test. Note: Please show how everything was

Sample z test

Directions: Perform a one sample z test for a population mean using the p value approach. Be sure to state the hypothese and the significance leve, to compute the value of the test statistics, to obtain the p value and to state your conclusion. Question: In 1990, the average duration of long distance telephone calls originati

General Statistics: Rejection Region, Critical Value Etc.

See the attached file. For each exercise, determine the a. rejection region b. nonrejectoin region c. critical value (s) d. significance level e. Identify the hypothesis test as two tailed, left tailed, or right tailed. 9.16 A graphical display of the decision criterion is: {see attachment} 9.18 A graphical displa