CHAPTER 4 HW POSC 301

What do you mean by Sample Variance, Sample Standard Deviation,and Standard Error?

18. An insurance agent has claimed that the average age of policy-holders who insure through him is less than the average for all agents, which is 30-5 years. A random sample of 100 policy-holders who had insured through him gave the following age distribution : Age last birthday 16-20 21-25 26-30 31-35 36-40 No. of persons 12 22 20 30 16 : Calculate the arithmetic mean and standard deviation of this distribution and use these values to test his claim at the 5% level of significance. You are given that Z (1-645) = (0-95.

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MEAN ABSOLUTE DEVIATION Q.1) Find the mean absolute deviation for the set below. S = {85, 90, 68, 75, 79} A. В. C. D. 79.4 6.48 32.4 79 Sherrie just registered for her wedding. So far 6 items have been fulfilled on her registry. Find the Q.2) mean price of the fulfilled items. $29, $58, $15, $129, $75, $22 43.5 129 54.7 114 А. В. С. D. Find the mean absolute deviation of the fulfilled items on Sherrie's registry. $29 , $58, $15, $129, Q.3) $75, $22 196 54.7 114 32.67 C. D.

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Suppose the profit a Honda dealership makes on the next 5 Accords it sells are:504, 1,027, 867, 1,434, 1,372. Calculate the standard deviation of the sample. (please express your answer using 2 decimal places).

Question 3 Saved 4) Listen A customer service team receives an average of 376 emails every day. Assume that the standard deviation for the number of emails is 96 emails. A random sample of 40 days was selected. a. What is the expected value of the sample mean? b. What is the standard deviation of the sample mean? Round your answer to two decimal places (e.g. 2.12). c. What is the probability that the average number of emails received was between 360 and 372? Round your answer to two decimal places with a leading zero (e.g. 0.18).

Calculate SP (the sum of products of deviations) for the following scores, Note: Bothmeans are decimal values, so the computational formula works well.X Y0 41 10 54 12 11 3

Answer is wrong should be 4.25

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I neeed help with all parts of this question

Could you help me with this homework question? I got an answer of 22.9

For the following time series plots, explain what type of transformation, if any, would make the variance more stable.

Consider a very large number of students taking a college entrance exam such as the SAT. And suppose the mean score on the mathematics section of the SAT is 570 with a standard deviation of 40.a. Find the z-score for a student who scored 600.b. A student is told that his z-score on this test is -1.5. What was his actual SAT math score?

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Suppose that SAT scores among U.S. college students are normally distributed with a mean of 500 and a standard deviation of 100. What is the probability that a randomly selected individual from this population has an SAT score between 500 and 600? 0.1587 0.3173 0.4207 0.3413

If the sample mean is 10, the standard deviation is 2 and the sample size is 100, what is the standard error? O 0,4 0.1 0.2 0.3

no.4 only

SCCoast, an Internet provider in the Southeast, developed the following frequency distribution on the age of Internet users. Find the mean and the standard deviation. (Round squared deviations to nearest whole number and final answer to 2 decimal places.)   Age (years) Frequency 10 up to 20   3   20 up to 30   7   30 up to 40   18   40 up to 50   20   50 up to 60   12

19 The mean of z-scores in a data set       a is zero only when the x-values are balanced around the mean of x. b is greater than zero for data sets that have large outlying values. c is always equal to one.         d is always equal to zero

Question of the day: A machine is designed to produce insulating washers for electrical devices of average thickness of 0.025 cm. A random sample of 10 washers was found to have an average thickness of 0.024 cm with a standard deviation of 0.002 cm. Test the significance of the deviation. Value of t for 9 degrees of freedom at 5% level is 2.262?

The state of California has a mean annual rainfall of 22 inches, whereas the state ofNew York has a mean annual rainfall of 42 inches (Current Results website, October 27,2012). Assume that the standard deviation for both states is 4 inches. A sample of 30 yearsof rainfall for California and a sample of 45 years of rainfall for New York has been taken.a. Show the probability distribution of the sample mean annual rainfall for California

QUESTION 28 "For a population with a mean = 440 and a standard deviation = 110, what is the X value corresponding to z = 2.67? (Be sure to round answer to the second decimal place)."

For the Given values ​​of 56, 67.9, 68, 53.8 and 69.8, Calculate a) Mean b) Algebraic Sum of deviation c) Variance d) Standard Deviation.

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2572/quizzes/secured#lockdown Continuous Question 2 Classify the random variable as either discrete or continuous. The number of runs scored in a 9 inning baseball game. O Discrete O ContinuouS Question 3 Larger values of the standard deviation result in a normal curve shifted to the right

Suppose a baker wants to know, on average, how many pastries they sell in a day. They sampled over 4 days. On the first day they sold 10, on the second day they sold 12, on the third day they sold 18, and on the fourth day they sold 16. The population standard deviation of pastry sales is 3. What is the point estimate (average) number of pastries sold? 26 08 056 O 14 Nex

b(Y)=400Y-6Y2 c(Y)=5y2