### Role of population standard deviation in hypothesis testing

1.Discuss and compare testing a claim about a mean when: - the population standard deviation is known - the population standard deviation is unknown

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1.Discuss and compare testing a claim about a mean when: - the population standard deviation is known - the population standard deviation is unknown

Problem #1 According to the control plan, 8 bolts will be measured every half hour and the machine will will be stopped if it is out of adjustment. Ninety-five percent of the bolts should be within 4+ or - .0004 inches. The last act of 8 showed the following measurements: 4.001 3.998 4.009 3.997 3.990 4.002 3.998

1. What is the term Bayesian statistics used to indicate? 2. What are the states of nature? 3. What is a variable? 4. What is a z score? 5. How does a z score differs from a t score? 6. What does the symbol sX represent? 7. What is the symbol for standard deviation? 8. What is one formula that we can use to calcula

16. Millionaires: The ages of the 36 millionaires sampled are arranged in increasing order in the following table. 31 38 39 39 42 42 45 47 48 48 48 52 52 53 54 55 57 59 60 61 64 64 66 66 67 68 68 69 71 71 74 75 77 79 79 79 a. Determine the quartiles for the data. b. Obtain and interpret the interquartile range.

Suppose that when a transistor of a certain type is subjected to an accelerated life test, the lifetime X (in weeks) has a gamma distribution with mean ... (see attachment)

1. Compute the mean, median, and mode for each of the following distributions. A B C D 3 2 1 2 3 2 3 3 4 2 3 4 6 5 3 4 7 5 5 4 8 7 5 5 10 7 8 7 8 8 8 10 8 8 11 9 11 2. I grew up in a very tiny town in the Midwestern United States. The two had seven streets, and the number of buildings on each street were a

In the process of acquiring data for research, we sometimes find ourselves facing possibility that field workers may have intentionally introduced error into the data. (A) Why and how might they have done this? (B) What can we do to prevent such errors?

A researcher is interested in the average amount of sugar that kindergarten kids eat per day within 4 grams. In a preliminary sample of 36 kids, the amount consumed ranged from 105 grams to 305 grams. The researcher wants to be 97% confident that the margin of error will not be exceeded. How large of a sample must she do if sh

The number of cars that travel through an intersection between noon and 1pm is measured for 30 consecutive days. The results of the 30 observations are: 61,62,63,63,64,64,66,66,67,68,68,68,68,69,69,69,69,70,70,70,70,71,71,72,73,74,74,75,76,and 79 Find: a.) Range b.) Standard Deviation c.) The population standar

A box and whisker plot is used to display data. Explain what box and whisker plots shows us. Provide example. Thanks.

An investor wants to invest 1000 euro. He can choose between the shares of the electronic company Solips and the food supply chain Bhold. The value of the first share is 1 euro at the moment the investment is made, the price of the second share is 2 euro. How should the investor divide the 1000 euro between the two types of shar

Please see the attached MS Word Document. It shows a table with three variables and the min, max, mean and SD for the each variable. I'm trying to determine what the rlationship is between the mean and SD for each variable. Introduction to Social Research Methods As part of an assignment I am working on I have the followin

Suppose that we want to estimate the mean germination time of strawberry seeds. The germination times for the sample of strawberries we choose has a mean of days and a standard deviation of days. For each of the following sampling scenarios, determine which test statistic is appropriate to use when making inference statements

You are given the following data for the number of times a population of six families dined out during the previous month: 4 6 9 4 5 7 a. Compute the mean, median and mode for this data. b. Compute the range for this data. c. Compute the variance and standard deviation. d. Assume that these data represent a sample rat

The manager of the 420-room SleepyTime Hotel is trying to decide how many rooms to reserve for vacationers who book less than two weeks in advance. Demand for the "early booking" rooms is unlimited at the price of $240/day. Demand for the "late booking" rooms averages around 120 rooms/day, and varies by about 15 rooms/day. Th

The mean price of 7 Hewlett Packard computers is $815 with a standard deviation of $19. The mean price of 9 IBM computers is $845 with a standard deviation of $9. If the alpha value is 0.05, can a computer shopper conclude that the IBM computers cost more? a. yes, there is enough evidence to conclude IBM computers cost more

What kind of test is used if the population standard deviation is not known and is less than 30?

1. What are standard deviation, mean, and variance for sample and populations and what Greek letters represent them? Give examples please.

Calculating the mean and variance for different portfolios.

Sample data was collected in a study of calcium supplements and their effects on blood pressure. A placebo group and a calcium group began the study with blood pressure measurement. At a 0.05 significance level, test the claim that the 2 sample groups come from populations with the same mean. Placebo mean: 114.6538, standard d

The time taken to install bumpers on cars passing through a particular assembly line is normally distributed with mean time u=2.00 minutes and standard deviation =36 minutes. A sample on n=100 is obtained and a mean bumper installation time X-bar will be calculated. 1. Find the value of standard deviation X bar. Determine th

1. Bill has completed a ten question multiple choice test on which he answered seven questions correctly. Each question had one correct answer to be chosen from four alternatives. Bill says that he answered the test by randomly selecting the answers without reading the questions or answers. a. What is the expected number of