Let X be a random variable with X -3 and oz = 5. Find the mean and the variance of Y = -2X -3
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Q: Let x be a random variable that represents red blood cell count (RBC) in millions of cells per cubic…
A: Answer Given The population mean= 4.78This is left-tailed test.
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- Let X be a random variable that represents red blood cell count (RBC) in millions of cells per cubic millimeter of whole blood. Then X has a distribution that is approximately normal. For the population of healthy female adults, suppose the mean of the X distribution is about 4.84. Suppose that a female patient has taken six laboratory blood tests over the past several months and that the RBC count data sent to the patient's doctor are as follows. 4.6 4.7 4.7 4.5 4.5 4.1 (i) Use a calculator with sample mean and standard deviation keys to find x and s. (Round your answers to two decimal places.) x = s = (ii) Do the given data indicate that the population mean RBC count for this patient is lower than 4.84? Use ? = 0.05. (a) State the null hypotheses H0 and the alternate hypothesis H1 . H0 : μ ---Select--- ≥ ≤ > ≠ < = H1 : μ ---Select--- ≠ < = ≥ > ≤ (b) What is the value of the sample test statistic? (Round your answer to three decimal places.)(c)…A least squares line is given by = 3 + (-2)*x. You are told that the sample variance of x is 25 and sample variance of y is 144. What is the value of the correlation coefficient r?A correlation of +.20 means that [blank] of the variance in the outcome variable is accounted for by the predictor variable.
- If independent random variables 'X' and 'Y' have the variances 36 and 16 respectively, find the correlation coefficient between (X + Y) and (X- Y) assuming X and Y are zero mean.The weight of cereal boxes (y) follows a normal distributed with a variance of 0.1 squared ounces. If the average is 15.8 ounces, then P(y < 16) = If the average is 16.5 ounces, then P(y > 16.2)Let x be a random variable that represents red blood cell count (RBC) in millions of cells per cubic millimeter of whole blood. Then x has a distribution that is approximately normal. For the population of healthy female adults, suppose the mean of the x distribution is about 4.78. Suppose that a female patient has taken six laboratory blood tests over the past several months and that the RBC count data sent to the patient's doctor are as follows. 4.9 4.2 4.5 4.1 4.4 4.3 (i) Use a calculator with sample mean and standard deviation keys to find x and s. (Round your answers to two decimal places.) x = s = (ii) Do the given data indicate that the population mean RBC count for this patient is lower than 4.78? Use ? = 0.05. (a) What is the level of significance?State the null and alternate hypotheses. H0: ? < 4.78; H1: ? = 4.78H0: ? = 4.78; H1: ? ≠ 4.78 H0: ? = 4.78; H1: ? < 4.78H0: ? = 4.78; H1: ? > 4.78H0: ? > 4.78; H1: ? = 4.78 (b) What sampling…
- Scores on a certain exam are normally distributed with a mean of 90 and a variance of 25. What is the z-value for a score of 80? -2.0 -0.4 1.0 2.0 0.42.1 In each of the following find the pdf of Y. Show that the pdf integrates to 1. (a) Y = X³ and ƒx(x) = 42x³(1 − x), 0 < x < 1A researcher found a significant correlation of .12 between gender (coded as 0 = ‘male’ and 1 = ‘female’) and number of friends at university. If the assigned values of gender were changed to 1 = ‘female’ and 2 = ‘male’, how would this affect the correlation? The strength of the relationship would become weaker The amount of variance explained by the relationship would increase It would become nonsignificantThe sign would change to become negative A researcher is trying to predict anxiety (measured on a 7-point scale) from exposure to stress (operationalised as the number of stressful life events participants can recall in the last week). She has found a correlation coefficient of r = .54 between anxiety and stress, with a standard deviation of 4.45 for anxiety and a variance of 17.21 for stress. What other information is needed to calculate b? The sums of squares of stressThe sums of products of anxiety and stress The covariance of anxiety and stressNo other information is…
- A set of n=15 pairs of scores (x and y values) has Ssx =200, Ssy=60, and Sp=30.What is the Pearson correlation for these data?Suppose Y1, Y2 and 3Y are not correlated variables, however, have the same standard deviation. Show that correlation between Y1 + Y2 and Y2 + Y3 is equal to half. Whether correlation coefficient is zero or notLet x be a random variable that represents red blood cell count (RBC) in millions of cells per cubic millimeter of whole blood. Then x has a distribution that is approximately normal. For the population of healthy female adults, suppose the mean of the x distribution is about 4.64. Suppose that a female patient has taken six laboratory blood tests over the past several months and that the RBC count data sent to the patient's doctor are as follows. 4.9 4.2 4.5 4.1 4.4 4.3 (1) Use a calculator with sample mean and standard deviation keys to find x and s. (Round your answers to two decimal places.) x=| S= (ii) Do the given data indicate that the population mean RBC count for this patient is lower than 4.64? Use a = 0.05. (a) What is the level of significance? State the null and alternate hypotheses. Ο Hg: μ= 4.64; H1: μ 4.64 Ο Ηρ: μ> 4.64; H1: μ = 4.64 Ho: u = 4.64; H1: u * 4.64 (b) What sampling distribution will you use? Explain the rationale for your choice of sampling distribution. O…
