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Coin flipping problem and SSE calculation

A coin is flipped 5 times in a row. What is the probability that it will come up heads all 5 times? For the data in question above, calculate the Sum of Squares Error (SSE).

Inverted Gamma Distribution

5. If X gamma(alpha, beta), then Y=1/X has the inverted gamma distribution. (a) Derive the form of the pdf; (b) verify that it is a pdf; (c) and calculate the mean and variance 6. Let X be a positive random variable, i.e. P(X greater or less than 0) = 0. Prove that E(ln(1/x) greater of less than ln(1/E(X)).

Statistics Practice

Let X have a binomial distribution. Find the distribution of Y. See attached file for full problem description.

Roulette Probabilities

A success, s in Bernoulli trials is often derived from the collection of outcomes. For example, an American roulette wheel consists of 38 numbers, of which 18 are black, 18 are red, and 2 are green. When the roulette wheel is spun, the ball is equally likely to land on any one of the 38 numbers. If you're interested in which num

What is the probability that between 2 and 6 customers inclusive want hot peppers?

1) Elly's hot dog emporium is famous for chili dogs. Some customers order hot dogs with hot peppers, while many do not care for the extra zest. Elly's latest taste test indicates that 30% of the customers ordering her chili dogs order it with hot peppers. Suppose 18 customers are selected at random. What is the probability that


(27) A company is in the process of hiring new employees for its sales force. The Human Resource manager estimates that the following are the probabilities of how many sales people will be hired during the next three months: No. To Be Hired Probability 0 5% 1 10% 2 20% 3 20% 4 25% 5 10% 6 10% What is the expected numb

Airport scanning Bayesian probability

1. Suppose an airport scanning device has 98% accuracy in detecting certain kinds of metal objects (98% of people carrying these objects are correctly identified as carriers and 98% of people not carrying them are correctly identified as non-carriers). Suppose that 1% of all travelers actually carry such metal objects. For the 1

Deaths Stats

1. In a recent year, there were approximately 97,000 deaths in the United States (total population 281 million) due to accidents. Approximately 25,000 of these accidental deaths involved people age 75 or older. Roughly 42,000 of these deaths were due to automobiles and 17,000 involved falls. a. Find the overall death rate for

Binomial and Normal Variable

1. A manufacturer of window frames knows from long experience that 5 percent of the production will have some type of minor defect that will require an adjustment. What is the probability that in a sample of 20 window frames: a. None will need adjustment? b. At least one will need adjustment? More than two will need

Business Statistics - Probability, Sampling,

See attached file for full problem description. — 1. The 1996-97 mean annual starting salary for accounting majors was $30,393 (U.S. News On-line. December 28, 1997). Assume that for the population of graduates with accounting majors the mean annual starting salary is pr = $30,393 and the standard deviation is 0 = $20

Probability Questions: What is the probability of acceptance into a school?

1. A school in Bangkok requires that students take an entrance examination. After the examination, there is a drawing where 5 students are randomly selected from each group of 40 for automatic acceptance into the school, regardless of their performance on the examination. The drawing consists of placing 35 red and 5 green pie

Probability Questions in Excel

1. A landscape contractor bids on jobs where he can make 3000 profit. Probabilities of getting one, two, three or four jobs per month are shown. #Jobs 1 2 3 4 Probability 0.2 0.3 0.4 0.1 Find contractor's expected profit per month 2. If a player rolls two dice and gets a sum of 2 or 12 she wins 20.00. If the person get a

Probability of Side Effects of Anesthetics

Anesthesia question (I prefer you do not use the Student t test nor Chi-square) A side effect of a certain anesthetic used in surgery is the hiccups, which occurs in about 10% of the cases. If three patients are scheduled for surgery today and are to be administered this anesthetic, compute the probability that: a. All thr

Explanations for Various Probability Questions

Question D An experiment consists of tossing an ordinary coin five times. Recall that an experiment can produce one or more sample spaces depending on what we consider our outcome to be. Consider the following 4 sets: (a) S = {zero heads, one head, two heads, four heads, five heads} (b) S = {no heads, no tails, at least one

Probability of Radio Failure

A radio has a failure rate of .22 x 10-5. If the radio operates for 1000 hours, what is the probability that the radio will not fail? Please work as an example and show work.

Poisson Statistics Distribution for Failure of a System

A system is tested for 10,000 hours and experiences 2 failures. Its failure rate is believed to be Poisson distributed. a. What is the probability of no failures in 5000 hours of operation of this system? b. If two of these systems are operated 1500 hours each, what is the probability of no failures in the two systems?

Probability questions about students in various classes

4. Of the 47 people who answered "yes" to a question, 8 were male. Of the 100 people who answered"no" to the question, 12 were male. If one person is selected at random from the group, what is the probability that the person answered "yes" or was male? A) 0.456 B) 0.401 C) 0.136 D) 0.17 5. A teacher designs a test so a

Normal/approximation to Binomial

Disregard #3- Part C. Thanks 1. If you determine that for the graph of a standard normal distribution the cumulative area to the left of a z core is 0.4, what is the cumulative area to the right of that z score? 2. Assume that the readings on the thermometers are normally distributed with a mean of 0 degree and a standard


Problem 2: An army is composed of 5 divisions. Each division has 10,000 soliders. In each regiment the desertion rate is 2 soldiers per month. DESERTERS ARE REPLACED. a) Find the probability that in the army as a whole there will be 3 or more desertions in a given month. b) What is the probability that there will be

Two probability questions

6) One must select from a set of 12 components that are known to contain 4 faulty components. The selection is made at random so that a selection of any component is equally likely. a) What is the probability of drawing exactly 1 faulty component if 3 different components are drawn? b) What is the probability of drawing

Discussing Discrete Probability Distributions

Thirty percent of the population in a southwestern community are Spanish-speaking Americans. A Spanish-speaking person is accused of killing a non-Spanish speaking American. Of the first 12 potential jurors, only 2 are Spanish-speaking Americans, and 10 are not. The defendant's lawyer challenges the jury selection, claiming bias

Multiple Choice

Look up the value of p=.25, n=8 and r=6 in order to calculate the probability of 6 successes out of 8 trials. 1. What is the probability of exactly six out of eight businesses succeeding when the probability of success is.20? a. 0.001 b. 0.01 c. 0.90 2. What is the probability of 0,1,2,3,4,5,6,7, and 8 businesses succee

Discrete Probability Distributions

1. A researcher calculates the expected value for the number of girls in five births. He gets a result of 2.5. He then rounds the result to 3, saying that it is not possible to get 2.5 girls when five babies are born. Is this reasoning correct? 2. A researcher reports that when groups of four children are randomly selected

Probability of attaining different grades in a statistics class.

In a large section of statistics class, the points for the final exams are normally distributed with a mean of 72 and a standard deviation of 9. Grades are to be assigned according to the following rule. 1) the top 10% receive A 2) the next 20% receive B 3) the middle 40%receive C 4) the next 20% receive D 5) the bott

Mean Height of 70 Women Sampling Distribution

(See attached file for full problem description) The mean height of women in a certain population (ages 20-29) is mu = 66 inches. A random sample of 70 women in this age group is selected. What is the probability that the mean for the sample, is greater than 66.8 inches? Assume sigma = 2.75 inches. --- PLEASE USE EXCEL F

Probability and Random Selection

1) When writing about the probability that it will rain in Boston on July 4 of next year, a newspaper reporter states that the probability is 1/2, because either it will rain or it will not. Is this reasoning correct? 2) In a recent year, 389 of the 281,421,906 people in the United States were struck by lighting. Estimate t