Two plots at Rothamsted Experimental Station were studied for production of wheat straw. For a random sample of ycars, the annual wheat straw production (in pounds) from one plot was as follows. 6.40 7.03 7.17 6,96 7.31 7.18 7.06 5.79 6.24 5.91 6.14 Use a calculator to verify that, for this plot, the sampie variance is s2 0.317, Another random sample of years for a second plot gave the following annual wheat production (in pounds). 7.10 7.03 8.15 5.91 7,22 5.58 547 5.86 Use a calculator to verify that the sample varlance for this piot is s? 0.933, Test the claim that there is a difference (either way) in the population variance of wheat straw production for these two plots, Use a 5% level of signifcance. (a) What is the level of significance? O 05 State the nuli and aiternate hypetheses. O H 0 > 0,, ,0 -, (b) Find the value of the sample/ statistic. (Use 2 decimal places.) What are the degrees of freedom? df dfo What assumptions are you making about the original distr bution? O The populations folluw independent normal distrbutions. We have random samples trom each population. O The populations follow independent chi-square distributions. We have randon samples Irom eeth pepulatien.

You have an independent-measures study where your first sample has an s² = 9 and your second sample has an s? = 6. a. If your sample size for both samples is n= 5, find the sample variances and compute the pooled variance. b. On the other hand, if your samples have difference sample sizes, n1 = 5 and n2 13. Again, calculate the two sample variances and your pooled variance, c. Compare your answers from part a and b. Why are there differences?

A researcher takes sample temperatures in Fahrenheit of 16 days from San Francisco (Group 1) and 22 days from Atlanta (Group 2). Test the claim that the mean temperature in San Francisco is less than the mean temperature in Atlanta. Use a significance level of a = 0.10. Assume the populations are approximately normally distributed with unequal variances. You obtain the following two samples of data. Round answers to 4 decimal places. San Francisco 77.4 94.8 77 80.9 84 Ho: M₁ 73.4 84.9 92 60.6 83.6 92.5 76.3 93.4 87.2 81.5 70.4 What are the correct hypotheses? Note this may view better in full screen mode. Select the correct symbols for each of the 6 spaces. Atlanta 85.4 92.8 80.2 87.9 80.6 77.9 72.9 75.9 72.1 76.7 80.4 92.5 75.9 72.1 97.7 89.2 88.1 80 92.2 86 96.2 91.9 p-value H₁: M₁ Based on the hypotheses, find the following: Test Statistic = -0.635 X = 0.2494 × OH₂ The p-value is greater than alpha OF H₂ to alpha. The correct decision is to fail to reject the null hypothesis or The…

A researcher takes sample temperatures in Fahrenheit of 17 days from New York City and 18 days from Phoenix. Test the claim that the mean temperature in New York City is different from the mean temperature in Phoenix. Use a significance level of α=0.05. Assume the populations are approximately normally distributed with unequal variances. You obtain the following two samples of data. New York City Phoenix 99 94.2 95.5 72 93.2 86.8 102 122.1 85.4 114.4 80 94.7 86.4 89.7 75.4 104.7 79.5 77.6 83.4 106.8 64.3 98.6 65.5 91.5 87.7 82 104 97.7 74.3 64.9 59.5 82 82.8 72   116.2 The Hypotheses for this problem are: H0: μ1 = μ2 H1: μ1μ2 Find the p-value. Round answer to 4 decimal places. Make sure you put the 0 in front of the decimal. p-value =