We want to estimate mean of a distribution by taking i.i.d. measurements, and computing their sample mean. Suppose we might be able to improve the precision of the measurements by refining the experiments, meaning we might be able to reduce the variance of the measurements (up to a point). Assuming we want to estimate the mean by conducting exactly 100 experiments, with an error of at most 1 unit and 99% certainty, how low should the variance be (approximately)?

Q: If sum of squares of deviation from the mean =20  and sample variance is 5  then the  number of…

A: Given, sum of squares=20 variance=5 number of observations=?

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Q: 1. Calculate a point estimate for the true population average unemployment duration.

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Q: to population variance, we get an estimate of the sample variance by ① . This is known as ② . This…

A: Population Mean and Variance μ = 1n∑i=1nxiσ2 =1n∑i=1nxi-μ2 Sample mean and variance x¯=1N∑i=1Nxi…

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Q: Suppose that you draw a random sample from a population where you know the population mean is 36 and…

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Q: 1. Let a denote the body temperature of a human. You read a report that claims the variance of human…

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Q: Suppose that we have disjoint normal populations A and B and we want to find the standard error…

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Q: Compute the values a and b such that the fit of type aX+b provide the desired mean and variance?

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Q: Suppose Y is distributed with mean=80 and variance=100. You obtain a large number of samples each of…

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Q: Find a number L such that P|L 95. %3D Hint: A useful fact when using tables to find F-values is that…

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Q: A sample of difference scores has a mean of Mp = 5 with a variance of s = 100. If effect size is…

A: Mean, Md = 5Variance, s2 = 100

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A: State the hypotheses.

Q: Based on the information provided: 1. Calculate a point estimate for the true population average…

A: Ans.   Here  it is given that ,   Sample Size = n = 64                      and average unemployment…

Q: A population of scores has a mean of µ=70, a median of 65 and a mode of 60. What is the most likely…

A: From the provided information, Mean (µ) = 70 Median = 65 Mode = 60

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A: Xbar=20.1, n=50, variance(sigma^2)=10

Q: 11.2 A sample is selected from a population mean of u = 30. A treatment is administered to the…

A: Given : Population mean = μ = 30 Sample mean = x = 31.3 Sample Variance = s2 = 12 Sample Standard…

Q: An analysis of variance produces SSbetween = 40, SSwithin = 60, and an F-ratio with df = 2, 15. For…

A: It is given that: SSBetween=40SSWithin=60df1=dfBetween=2df2=dfWithin=15

Q: A population has a mean of μ = 100, a variance of σ2 = 9, and a standard deviation of σ = 3.  The…

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Q: 10. If the population has distribution of its means if the sampling distribution was derived with…

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Q: For data that is not normally distributed we can't use z-scores. However, there is an equation that…

A: As per the Chebychev’s formula

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A: The sample mean also follow normal distribution with following parameters

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Q: 5. Two different box-filling machines are used on an assembly line. The critical measurement…

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