Why should we be concerned about the presence of confounding variables/factors in statistical analyses? State an appropriate technique for dealing with confounding variables. (Provide a brief answer—no more than 2-4 sentences)

Q: (a) Perform a parametric analysis. (b) Perform a non-parametric analysis. (c) Compare the results…

A: ANOVA and design of experiment and non parametric test.  Null hypothesis: The average cholesterol…

Q: CNBC (2018) reported 75% of households are using streaming services compared to standard cable. What…

A: here given , CNBC (2018) reported 75% of households are using streaming services compared to…

Q: ion compan from customers reporting service troubles and from would-be subscribers to the cable…

A: Given distribution is normally distributed Let, X: Company's callers put on hold Mean=μ=3.1 Standard…

Q: What is the test statistic for this sample? (Report answer accurate to three decimal places.) test…

A: Here from Given Information n1 =593n2 =266p1^=0.30p2^=0.188

Q: Find the z-score that cuts off 65% in the body on the left.  (Hint: if you can’t find that EXACT…

A:

Q: Let x be a continuous random variable that has a normal distribution with u = 50 and a = 8. Find the…

A:

Q: Carry out the steps of hypothesis testing for a paired sample t-test with a 0.05 level of…

A: let, μ1 : mean of before workshopμ2 : mean of after workshop     x :  sample mean of the…

Q: calculate these mortality rates: A) Crude mortality rate due to cancer B) Age specific mortality…

A:

Q: Suppose each license plate in a certain state has one digit, followed by four letters, followed by…

A: Given, Each license plate in a certain state has one digit followed by four letters followed by one…

Q: Blood sugars from eight patients in a rural clinic were recorded last summer by the local physician.…

A: Given data is120, 145, 200, 250, 79, 100, 894, 255sample size(n)=8standard deviation(σ)=5confidence…

Q: A barber shop has homogeneous, independent arrivals every 10 minutes.  The interarrival times are…

A: Queuing theory

Q: Find the upper limit of 90% confidence interval.    An SRS of 154 students were taken from high…

A: Given n=Sample size=154 x=Number of success=83 Confidence interval=90%

Q: The lifetime of a certain residential air conditioner is normally distributed with a mean of 20…

A:

Q: You wish to test the following claim (Ha) at a significance level of α=0.10. For the context of this…

A:

Q: Which distribution should you use? You are approximating the proportion of the population in…

A: Sometimes observation are taken on qualitative characteristics. In this case number of observations…

Q: (a) Compute the value of the test statistic z. (b) Is Ho rejected at the a=0.10 level? (c) Is Ho…

A: It is given that  Mean, μ = 18 Sample mean, x̅ = 20 Standard deviation, σ = 7 Sample size, n = 65

Q: Calculate the standard deviation of the sample data shown below. 28 12 19 19 20 02.842 5.683 05.083…

A: The variation of the observations around the average value is determined by the standard deviation.…

Q: A random experiment involves drawing a sample of 12 data values from a normally distributed…

A: From the provided information, The data values are as follow: 47, 51, 53, 54, 56, 61, 61, 62, 63,…

Q: You wish to test the following claim (Ha) at a significance level of a = 0.10. H₁:1 = 2 Ηα: μι # με…

A: Given: n1 = 38 n2 = 39 α = 0.10 Formula Used: Test-statistic t = X1 - X2sp1n1+1n2 sp =…

Q: 19. Given the following econometric model Y₁ = P + B₁X₁ + U₁ What is the conditional expectation of…

A: Here u ~ Normal (0,1) Y = β0 + β1x + uHence, E (Y | X =x) = β0 + β1x + E(u) = β0 + β1x

Q: A manufacturer of salad dressings uses machines to dispense liquid ingredients into bottles that…

A: Parametric test are used when the population follows any of the distribution. There are types of…

Q: 5) How many five digit numbers are there that start and end with an odd digit and also the middle…

A:

Q: 1. Regarding Normal Approximation to the Binomial, one rule states that the Normal Approximation…

A: Normal approximation apply in binomial when np≥5 and nq≥5, here, n=sample size,          p= success…

Q: A standardized exam's scores are normally distributed. In a recent year, the mean test score was…

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Q: What conditions are necessary in order to use a t​-test to test the differences between two…

A: The objective is to identify the conditions that are necessary to use a t-test to test the…

Q: Explain the reason why the forecast for City A is more reliable than the forecast for the City B.…

A: Given the temperature data of the two cities

Q: 12) The distributions of income in the United States is strongly skewed to the right. Which of the…

A:

Q: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the…

A: Given that: The following statement is: The typical bus ride to school for a student living in the…

Q: Hypothesis test for the difference of population means: Paired comparisons Based on these data, can…

A: Given: n = 8 α = 0.05 Formula Used: Test-statistic t = dsdn

Q: P(x <83) P(x <83) = (Round to four decimal places as needed.) ....

A: It is given that  Mean, μ = 90 Standard deviation, σ = 5 Z-Score, Z = ( X - μ )/σ

Q: What conditions are necessary in order to use the dependent samples t​-test for the mean of the…

A: Necessary conditions for dependent samples in t-test, and for the difference in the means of two…

Q: In a recent survey at nursing homes in NY, there were 145 cases of Covid-19 among a total of 24,000…

A: Given that In a recent survey at nursing homes in NY, there were 145 cases of Covid-19 among a total…

Q: (0) Four letters are to be typed by each typist. (in) Each typist works for two hours.

A: Given that typist types letters in 15,10,6 and 5 minutes

Q: Jogging Status Low Joggers 34 Non-joggers 15 Total 49 Blood Pressure Moderate High 57 63 120 21 20…

A: Given data: Jogging status Low Moderate High Total Joggers 34 57 21 112 Non-joggers 15 63 20…

Q: A psychologist would like to examine the effects of a new drug on the activity level of animals.…

A: Null hypothesis: H0:µ1 = µ2 = µ3 Alternative hypothesis: H1: At least one of the means is different…

Q: The amount of annual snowfall in a certain mountain range is normally distributed with a mean of 70…

A:

Q: Match the following scenario with the appropriate statistical test found on the right drop down…

A: Introduction: The chi-square test can be used to test the in the following scenarios: To test the…

Q: Find the p-value (decimal rounded to nearest 4 places) A company claimed that 75% of their…

A:

Q: Use the following Distributions tool to identify the boundaries that separate the extreme samples…

A: Z-score is a measure that indicates how many standard deviations away, a data value lies from the…

Q: A recent court decision supported a pilots decision to continue to his destination with a four…

A: Given that: The argument was that an aircraft will fly on two engines and that the probability of…

Q: A type Il error is when you fail to reject the null hypothesis, but the null hypothesis is actually…

A: Given, σ=2, n=25 Null hypothesis : μ=5.1 Alternate hypothesis : μ&gt;5.1 Significance level=0.05

Q: hin 1 Distance o

A: Consumption of cigarette sticks for 30 Participants 4 10 4 7 8 7 8 7 9 3 6 2 3 9 9 4 10…

Q: Below is the standard deviation for extreme 10k finish times for a randomly selected group of women…

A: Answer:     The correct answer is option  (a).

Q: a) What is the probability that 8 or 9 new subscriptions come in the next 20 seconds? State the…

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Q: Determine the critical value of a right tailed to arding a population at the oool level OF…

A: Given that  Right tailed test  Level of significance (α) = 0.01 The normal distribution graph is as…

Q: 1) The amount of money spent on a haircut by a Math 119 class is right skewed with a mean of $33 and…

A: As per our guidelines we are suppose to answer only one question.   Given,mean(μ)=$33standard…

Q: What is the standard deviation reduction (SDR) in the "Time" attribute?

A: Statistics  Note that I used R software for my calculations.

Q: answers

A: Given Data:

Q: Provide a written description of the complement of the given event: "A manufacturer inspects the…

A: Complement events: Two events are said to be complement events, when one event occurs, the other…

Q: c) Find the probability that at least three defectives are found?

A: Here given ,  A manufacturing process that produces electron tubes is known to have a 10% defective…