2.3. The university is studying how to project its expenses and revenues regarding the staffing of an MBA course. The
...
MBA course. The university knows that the probability of a student completing the course successfully is 80%. We take a random sample of 4, independent students.
a. What is the probability exactly 0 students complete the course?
b. What is the probability exactly 1 student complete the course?
c. What is the probability exactly 2 students complete the course?
d. What is the probability exactly 3 students complete the course?
e. What is the probability 3 or (all) 4 of the students complete the course?
f. What is the expected number of students (out of the 4 sampled) that complete the
course?
g. What is the standard deviation of the number of students that complete the course?
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3.(1) The claim by a weight loss Company is that on average, the client will lose 10 pounds over
...
first 2 weeks. 50 people who joined the programme are sampled, their weight loss is 9 pounds with a standard deviation of 2.8 pounds. Can we conclude at the .05 level that a person joining the programme will lose less than 10 pounds?
(2) The following is a random sample of 90-day futures prices in dollars for 1 troy oz. of silver from The Wall Street Journal issues in May and June of 1997: 4.74, 4.77, 4.87, 4.91, 4.83, 4.72, 4.92, 4.86, 4.97, 4.71, 4.90, 4.93, 4.75, 4.88, 4.79, 4.83, 4.89.
Required:
a. Calculate the mean
b. Median
c. Standard deviation of the 90-day future price of silver data
(3) A mining company needs to estimate the average amount of copper ore per ton mined. A random sample of 50 tons gives a sample mean of 146,75 pounds. The population standard deviation is assumed to be 35.2 pounds.
Required:
a. Give a 95% confidence interval for the average amount of copper in the population of tons mined.
b. Give a 90% confidence interval for the average amount of coper per ton
c. Give a 99% confidence interval for the average amount of coper per ton
(4) An e-commerce Website gets 2,385 visitors on a particular day. Among these, 1790 visitors explore the products by looking at more pages at the site. Among these 1790 visitors who explore the products, 387 make a purchase.
Required:
a. If a visitor chosen at random from all those who visited the site, what is the probability that the visitor explored the products
b. If a visitor is chosen at random from all those who visited the site, what is the probability that the visitor made a purchase.
c. If a visitor is chosen at random from all those who explored the products, what is the probability that the visitor made a purchase.
d. Which of the preceding three probabilities is relevant to the design of the home page that leads to product page.
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8.It is estimated that during any one hour period, an average of 10 Internet users visit the
website of Sport-Equip Ltd,
...
of Sport-Equip Ltd, a company that sells sports equipment. Some of the users
who visit the website end up buying sports equipment from the website while others are
simply browsing in order to obtain product information.
(a) Clearly explain and justify which probability distribution you would use to
describe the number of Internet users who visit the website of Sport-Equip Ltd
in a one hour period. [There is no need to calculate any probabilities for this part
of the question]
(5 marks)
(b) What is the probability that during any half-hour period, there will be less than 3
visitors to the website?
(5 marks)
(c) What is the probability that during any two-hour period, there will be more than
15 visitors to the website?
(5 marks)
(d) If a user has just visited the website, find the probability that the website will
have another visitor within the next 10 minutes. In your answer, state the
probability distribution you have used and explain your choice.
(4 marks)
(e) It is estimated that 40% of Internet users who visit Sport-Equip Ltd’s website
buy a product from the company. If 100 users visit the website over a given
period of time, find the probability that more than 50 of them will buy a product
from the company. In your answer, state the probability distribution you have
used and explain your choice
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10.In a box there are 4 red, 4 blue and 3 white marbles. Two marbles are selected at random and
...
or is noted. Find the probability that neither is white given that neither is red.Round your answer to 4 decimal places
A place kicker in the NFLmakes 78% of his field goals. If the outcomes are independent, what is the probability that he makes exactly 6 of the next 8 field goals? Round your answer to 4 decimal places
There are 5 white mice and 3 gray mice in a cage. Three mice are selected at random and their colors are noted. Find the expected number of white mice.Round your answer to 2 decimal places
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13.11. In a game, you draw thirteen cards with replacement from a deck of playing cards. If you draw any
...
y aces or twos, you lose the game immediately. You also lose if you draw picture cards(J,Q,K) more than twice. In this question, you’ll study the probability of winning this game.(a) What is the probability of drawing no aces or twos after thirteen draws?(b) Given you have drawn thirteen times, none of which is aces or twos, what is the probability that you draw at most two picture cards?(c) What is the probability to win this game?
12. Suppose you are tossing an unbiased coin for100times.(a) What is the probability of getting50heads and50tails?(b) LetXbe the random variable counting the number of heads you observe in this exper-iment. What is the expected value ofX? What is the variance ofX? What is thestandard deviation ofX?
13. The following are probability distributions for two random variablesX,Y.
kPr(X=k)
0,0.4
1,0.3
2,0.3
kPr(Y=k)
0,0.5
1,0.3
2,0.2
(a) Construct the probability distribution table for the random variableXY.(b) Find E[X],E[Y] and E[XY]. Is is true that E[XY] =E[X]E[Y]?(c) Find the variances σ2X,σ2Y,σ2XY of X,Y and XY. Is it true that σ2XY=σ2Xσ2Y?
14. The aliens who are fond of gambling came back to play another game with you. In this game, you first toss a coin5times. If you observe3or fewer tails, you roll a die3times. If youobserve4or more tails, you roll a die20times. What is the probability that you end up with at most two6’s in your dice rolls?
15. (Challenge question, worth2points) You have two bags, each of which contains10marbles.Each time you remove a marble from a random bag. What is the probability that after one of the bags is emptied, there are still exactly3marbles in the other bag?
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23.Exercise 4) A fair coin is tossed. If it lands heads, a fair four-sided die
is thrown (with values 2,3,4,7). If
...
2,3,4,7). If it lands tails, a fair six-sided die is
thrown (with values 3,4,5,6,7,9). Regardless of which die is used, Alice
eats n grains of rice, where n is the largest prime factor of the die result
(for example, the largest prime factor of 9 is 3).
(a) What is the conditional probability that the coin lands heads, given
that Alice eats three grains of rice?
(b) Suppose that the entire experiment is conducted twice on the following day (starting with a new coin toss on the second run-through).
What is the conditional probability that the coin lands heads on both
run-throughs, given that Alice eats a total of five grains of rice during the two run-throughs?
(Do not count the two grains from part (a) in part (b); we assume
two brand new experiments, each with a new coin toss. Start your
solution by defining a suitable partition of the sample space. Please
use an appropriate notation and/or justification in words, for each
value that you give as part of your solution.)
Exercise 5) Alice and Bob throw an unfair coin repeatedly, with probability 2/5 of landing heads. Alice starts with £2 and Bob starts with £3 .
Each time the unfair coin lands heads, Alice gives Bob £1 . Each time
the unfair coin lands tails, Bob gives Alice £1 . The game ends when one
player has £5 .
(a) Draw a labelled Markov chain describing the problem, and write
down a transition matrix P. Write down the communication classes,
and classify them as either recurrent or transient.
(b) Using the transition matrix, calculate the probability that Alice loses
all of her money in exactly four tosses of the unfair coin.
(c) Calculate the (total) probability that Alice loses all of her money
(before Bob loses all of his).
(d) Calculate the expected (mean) number of tosses of the unfair coin,
for the game to end.
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29.Can domestic dogs understand human body cues such as leaning? The experimenter leaned toward one of two objects and recorded
...
two objects and recorded whether or not the dog being tested correctly chose the object indicated. A four-year-old male beagle named Augie participated in this study. He chose the correct object 42 out of 70 times when the experimenter leaned towards the correct object.
(a) (2 points) Let the parameter of interest, π, represent the probability that the long-run probability that Augie chooses correctly. Researches are interested to see if Augie understands human body cues (better than gussing).
Fill in the blanks for the null and alternative hypotheses.
H0 : Ha :
(b) (6 points) Based on the above context, conduct a test of significance to determine the p-value to investigate if domestic dogs understand human body cues. What conclusion will you draw with significance level of 10%? (If you use an applet, please specify which applet you use, and the inputs.)
(c) (5 points) Based on the above context, conduct a test of significance to determine the p-value to investigate if domestic dogs understand human body cues. What conclusion will you draw with significance level of 5%? (If you use an applet, please specify which applet you use, and the inputs.)
(d) (2 points) Are your conclusions from part (b) and (c) the same? If they are different, please provide an explanation.
(e) (5 points) Shown below is a dotplot from a simulation of 100 sample proportions under the assump- tion that the long-run probability that Augie chooses correct is 0.50. Based on this dotplot, would a 90% confidence interval for π contain the value 0.5? Explain your answer.
(f) (4 points) Compute the standard error of the sample proportion of times that Augie chose the object correctly.
1
(g) (5 points)
(h) (3 points) question?
(i) (4 points)
(j) (4 points) A.
B. C.
Construct an approximate 95% confidence interval for π using the 2SD method. What is the margin of error of the confidence interval that you found in the previous
How would you interpret the confidence interval that you found in part (g)?
Which of the following is a correct interpretation of the 95% confidence level?
If Augie repeats this process many times, then about 95% of the intervals produced will capture the true proportion of times of choosing the correct objective.
About 95% times Augie chooses the correct objective.
If Augie repeats this process and constructs 20 intervals from separate independent sam- ples, we can expect about 19 of those intervals to contain the true proportion Augie chooses the correct objective.
(k) (4 points)
object 21 out of 35 times.
Conjecture how, if at all, the center and the width of a 99% confidence interval would change with these data, compared to the original 2SD 95% confidence interval.
The center of the confidence interval would . The width of the confidence interval would .
(l) (4 points) Suppose that we repeated the same study with Augie, and this time he chose the correct object 17 out of 35 times, and we also change the confidence level from 95% to 99%. Conjecture how, if at all, the center and the width of a 99% confidence interval would change with these data, compared to the original 2SD 95% confidence interval.
Suppose that we repeated the same study with Augie, and this time he chose the correct
The center of the confidence interval would The width of the confidence interval would
.
.
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30.hI I need help with a FINITE MATH question. In a survey of high school graduates, it was found that
...
if a graduate went on to college full time, there was a 23% chance that they would work at the same time. If a graduate attended college part time, there was a 79% chance that they would work at the same time. If a high school graduate didn't go on to college, there was a 93% chance that they would work. At the time of the survey, 66% of high school graduates attended college full time and 20% of high school graduates attended college part time. If a randomly selected high school graduate worked, what is the probability that they attended college full time? Enter your answer in decimal form and round to four decimal places if necessary. You may want to look at pages 42 through 45 in the notes (videos 30 through 32).
If a randomly selected high school graduate worked, probability that they attended college full time =
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39.Suppose the heights of 18-year-old men are approximately normally distributed, with mean 65 inches and standard deviation 6 inches.
A button
...
nd standard deviation 6 inches.
A button hyperlink to the SALT program that reads: Use SALT.
(a) What is the probability that an 18-year-old man selected at random is between 64 and 66 inches tall? (Round your answer to four decimal places.)
Correct: Your answer is correct.
(b) If a random sample of seven 18-year-old men is selected, what is the probability that the mean height x is between 64 and 66 inches? (Round your answer to four decimal places.)
Incorrect: Your answer is incorrect.
(c) Compare your answers to parts (a) and (b). Is the probability in part (b) much higher? Why would you expect this?
The probability in part (b) is much higher because the standard deviation is smaller for the x distribution.
The probability in part (b) is much higher because the standard deviation is larger for the x distribution.
The probability in part (b) is much higher because the mean is smaller for the x distribution.
The probability in part (b) is much higher because the mean is larger for the x distribution.
The probability in part (b) is much lower because the standard deviation is smaller for the x distribution.
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40.Question 1
the population of a city was 67,000 people in 1990, and has grown exponentially at an average rate of
...
average rate of 1.1% since then, how many years later would the population arrive at 102.000 people? Give your answer as a number only, to the nearest tenths
Question 3
In a bag containing 5 red, 2 blue, 8 clear, and 1 purple marble, what is the probability of picking a blue marble, then without replacement, choosing a red marble on the second pick? (Leave in simplified fraction form.]
Question 11
Poaching is causing a population of elephants to decline by 6% per year. Determine how many elephants remain in 76 years if there are 13,365 elephants today. Round to the nearest whole number.
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41.Hello, I have a problem calculating probability for a certain thing that happened. I'll try and make it sound like
...
it sound like a math problem.
The problem :
What are the chances of a 4 sided die landing on 1 twice and on 2 twice out of 4 rolls. The solution I came up with originally was (2/4) x (2/4) x (2/4) x (2/4) . Which I realized was wrong as this allowed the die to land on 1 four times in a row. So then I came up with this soultion (which i still think is wrong) (2/4) x (2/4) x (1/4) x (1/4) . So the reasoning behind this is : The first roll obviously has a 50% chance to roll on either 1 or 2. Second roll is the same. BUT, lets say both of them land on 1, and now it HAS to land on 2 the remaining two times. So my problem is with the current solution that I have is what if the die lands on 1 on the first roll, then on two for the second one. then the third roll would still have a 2/4 AKA a 50% chance of landing on either one. I'm sure the last roll is 1/4 but I just dont know if the order matters on the rolls. This has been driving me crazy the last hour. Please help if you can thanks
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48.27. The Air force receives 30% of its parachutes from company C1 and the rest from company C2. The probability
...
robability that a parachute will fail to open is 0.0025 and 0.002, depending on whether it is from company C1 or C2, respectively.
a) What is the probability that a randomly chosen parachute will fail to open (rounded off to four decimals)?
b) If a randomly chosen parachute fails, what is the probability it came from company C1 (rounded off to four decimals)?
c) If a randomly chosen parachute fails, what is the probability it came from company C2 (rounded off to four decimals)?
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49.Hi, is it perhaps possible that I can get some assistance with the following question below? specifically b) and c)
...
cally b) and c) please?
The Air force receives 30% of its parachutes from company C1 and the rest from company C2. The probability that a parachute will fail to open is 0.0025 and 0.002, depending on whether it is from company C1 or C2, respectively.
a) What is the probability that a randomly chosen parachute will fail to open (rounded off to four decimals)?
Ans=0.0022
b) If a randomly chosen parachute fails, what is the probability it came from company C1 (rounded off to four decimals)?
c) If a randomly chosen parachute fails, what is the probability it came from company C2 (rounded off to four decimals)?
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50.Task 1
You are asked to carry out a study on behalf of a business analytics specialised consultancy on a subsample
...
on a subsample of weekly data from Randall’s Supermarket, one of the biggest in the UK. Randall’s marketing management team wishes to identify trends and patterns in a sample of weekly data collected for a number of their loyalty cardholders during a 26-week period. The data includes information on the customers’ gender, age, shopping frequency per week and shopping basket price. Randall’s operates two different types of stores (convenient stores and superstores) but they also sell to customers via an online shopping platform. The collected data are from all three different types of stores. Finally, the data provides information on the consistency of the customer’s shopping basket regarding the type of products purchased. These can vary from value products, to brand as well as the supermarket’s own high-quality product series Randall’s Top. As a business analyst you are required to analyse those data, make any necessary modifications in order to determine whether for any single customer it is possible to predict the value of their shopping basket.
Randall’s marketing management team is only interested in identifying whether the spending of the potential customer will fall in one of three possible groups including:
• Low spender (shopping basket value of £25 or less)
• Medium Spender (shopping basket value between £25.01 and £70) and
• High spenders (shopping basket greater than £70)
For the purpose of your analysis you are provided with the data set Randall’s.xls. You have to decide, which method is appropriate to apply for the problem under consideration and undertake the necessary analysis. Once you have completed this analysis, write a report for the Randall’s marketing management team summarising your findings but also describing all necessary steps undertaken in the analysis. The manager is a competent business analyst himself/herself so the report can include technical terms, although you should not exceed five pages. Screenshots and supporting materials can be included in the appendix.
Requirements
After completing your analysis, you should submit a report that consists of two parts. Part A being a non-technical summary of your findings and Part B a detailed report of the analysis undertaken with more details.
Part A: A short report for the Head of Randall’s Marketing Management (20 per cent). This should briefly explain the aim of the project, a clear summary and justification of the methods considered as well as an overview of the results.
Although, the Head of Randall’s Marketing Management team who will receive this summary is a competent business analytics practitioner, the majority of the other team members have little knowledge of statistical modelling and want to know nothing about the technical and statistical underpinning of the techniques used in this analysis. This report should be no more than two sides of A4 including graphs, tables, etc. In this report you should include all the objectives of this analysis, summary of data and results as well as your recommendations (if any).
Part B: A technical report on the various stages of the analysis (80 per cent).
The analysis should be carried out using the range of analytics tools discussed:
• SPSS Statistics
Ensure that the exercise references:
• Binary and multinomial logistic regression
• Linear vs Logistic regression
• Logit Model with odds Ratio
• Co-efficients and Chi Squared
• MLR co-efficients
• Assessing usefulness of MLR model
• Interpreting a model
• Assessing over-all model fit with Psuedo R-Squared measures
• Classification accuracy (Hit Ratio)
• Wald Statistic
• Odd ratio exp(B)
• Ratio of the probability of an event happening vs not happening
• Ratio of the odds after a unit change in the predictor to the original odds
• Assumptions
• Residuals analysis
• Cook’s distance
• DfBeta
• Adequacy (with variance inflation factor VIF and tolerance statistic)
• Outliers and influential points cannot just be removed. We need to check them (typo? – unusual data?)
• Check for multicollinearity
• Parsimony
Write a short and concise report to explain the technical detail of what you have done for each step of the analysis.
The report should also cover the following information:
• Any type of analysis that might be useful and check whether the main assumptions behind the analyses do not hold or cannot be
• Give evidence of the understanding of the statistical tools that you are using. For example, comment on the model selection procedure and the coefficient interpretation, e.g. comment on the interpretation of the logistic regression coefficients if such a method is used and provide an example of
• Conclusions and explanation, in non-technical terms, of the main points
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56.I'm checking my answers for a practice ACT exam I did, and I am confused by this question on probability...
"As
...
lity...
"As part of a probability experiment, Elliott is to answer 4 multiple-choice questions. For each question, there are 3 possible answers, only 1 of which is correct. If Elliott randomly and independently answers each question, what is the probability that he will answer the 4 questions correctly?"
Solving the question I keep getting 1/256. My reasoning is that each question has a 1/4 chance of being right if you guessed, so 1/4 x 1/4 x 1/4 x 1/4 = 1/256.
But my answer choices are as follows, with the correct answer being E:
A. 27/81
B. 12/81
C. 4/81
D. 3/81
E. 1/81
Am I missing something? Or am I just completely solving this wrong?
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57.Credit card sales The National Association of Retailers reports that 62% of all purchases are now made by credit card;
...
de by credit card; you think this is true at your store as well. On a typical day you make 20 sales.
Show that this situation can be modeled by a binomial distribution. For credit, you must discuss each of the criteria required for a binomial experiment.
Define the random variable x in this scenario, using the context of the problem.
List all possible values of x for this situation.
On one trial for this scenario, what does “success” mean? Explain using the words of the problem.
What is the probability of success in this scenario?
What is the probability of failure in this scenario?
Probability Distribution Instructions¬¬¬¬
In Excel, create a probability distribution for this scenario.
Label Column A as “x” and Column B as “P(x).”
In Column A, list the numbers 0 to 15.
In Column B, use BINOM.DIST.RANGE to calculate the probability for each x value.
Highlight the probability cells, then right click and select Format Cells. Format the probability cells as “Number” and have Excel show 4 decimal places.
Create a probability histogram using the probabilities you calculated. Format and label it properly. Be sure to use the “Select Data” button to change the x-axis so it correctly lists the x-values.
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65.Twenty students are asked to select an integer between 1 and 10. Eight choose either 4, 5 or 6.
a If
...
f the students make their choices independently and each is as likely to pick one integer
as any other, what is the probability that 8 or more will select 4,5 or 6?
b Having observed eight students who selected 4, 5, or 6, what conclusion do you draw based
on your answer to part (a)?A missile protection system consists of n radar sets operating independently, each with a
probability of .9 of detecting a missile entering a zone that is covered by all of the units.
a If n = 5 and a missile enters the zone, what is the probability that exactly four sets detect
the missile? At least one set?
b How large must n be if we require that the probability of detecting a missile that enters the
zone be .999?
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71. The probability of a success is 0.2 for each of 10 trials. What is the probability that one gets
...
actly 3 successes and 7 failures if each trial is independent of the others? What is the probability that only the first, third and fifth trials are successes and the rest are failures?
3 One is dealt 6 cards from a standard poker deck of 52 cards. What is the probability of getting 3 aces and 3 kings? What is the probability of getting the same except both pairs kings and aces are of the same suit (e.g., the same suit is missing from both).
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75.How to calculate the probability of "A" given multiple other events? Example, let's say i have a deck of 10
...
k of 10 cards numbered 1-10. I draw 5 cards (each time i draw i put the card back and shuffle). The numbers were 8, 2, 4, 9, and 4. What is the probability that it will be 4 on the 6th time i draw? I know each card has a 10% chance of being drawn. I also know the probability of a 10% event happening twice is 1%. But wouldnt the odds be lower since i drew 4 a couple trials earlier? How exactly would i calculate that. If there is an online calculator that executes the answer id like to know. Just a college student who craves probability. :)
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82.One state lottery game has contestants select 5 different numbers from 1 to 45. The prize if all numbers are
...
bers are matched is 2 million dollars. The tickets are $2 each.
1) How many different ticket possibilities are there?
2) If a person purchases one ticket, what is the probability of winning? What is the probability of losing?
3) Occasionally, you will hear of a group of people going in together to purchase a large amount of tickets. Suppose a group of 30 purchases 6,000 tickets.
a) How much would each person have to contribute?
b) What is the probability of the group winning? Losing?
4) How much would it cost to “buy the lottery”, that is, buy a ticket to cover every possibility? Is it worth it?
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84.∗ The jokes in the Christmas crackers sold by a well known supermarket are written by 3 comedians: Andrew, Beryl
...
Andrew, Beryl and Charlie. Beryl is the most prolific writer, writing 55% of the jokes, with Andrew and Charlie writing 30% and 15% respectively. 98% of Andrew’s jokes are puns and 95% of Beryl’s jokes are puns, whilst only 90% of Charlie’s jokes are puns. Suppose you pull a cracker and find that the joke inside is not a pun. (i) What is the probability that Andrew wrote the joke? (ii) What is the probability that Beryl wrote the joke? (iii) What is the probability that Charlie wrote the joke?
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88.Hi! I need help with part (c) of this question. I have already done part (a) & (b):
A recent poll
...
conducted by Gallup Inc. asked the following question:
In general, how much trust and confidence to you have in the mass media - such as newspapers, TV, and radio - when it comes to reporting the news fully, accurately, and fairly? A great deal, a fair amount, not very much, or non at all?
53% of respondents has a negative view of the media, meaning they responded with either not very much or non at all.
Two people are randomly chosen, each is asked the poll question above. What is the probability
Part (a) that both have a negative view of mass media? 0.53^2
Part (b) neither have a negative view of the mass media? 0.47^2
Part (c) at least one of the two has a negative view towards the media? .53 (<- wrong)
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99.Hi there, I am a senior with a curious eye. I am looking at statistics tutoring, specifically:
ANOVA (refresher), linear
...
A (refresher), linear regression, logistic regression, multivariate regression, chi square test (refresher), and more. CLT is a given, so are probability distributions;
I eat MC simulations for breakfast. I only work in Excel; not so much interest in Crystal Ball and other add-ins; I have created my own VBA Excel functions such as Spearman(), triangularprobabilitydist() and PoissonInv().
So hit me with what you got, I am up to the challenge. looking for some fun and challenging time.
Availability evenings and weekends; looking at 20+ hours of tutoring over next 6 weeks.
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101.I have the following budget constraints for an agent. In the first period of his life, he only can get
...
et loans (he doesn't "earn" income). With the loans (L) he needs to decide between first period consumption (C1) and investment (I). The amount invested will allow him to get a second period income Y with probability P which is increasing in I (therefore, P(I)), In case of success and the person obtain Y, the individual should use Y to repay the loan (L) that he requested in the first period and consume in the second period (C2). However, with probability 1 - P(I), the person don't get Y and therefore only consume C1. Note that if the individual only invest the loan (L=I) and don't obtain Y, he can't consume anything. That motivates him not to invest the whole loan and keep part of the loan in order to warrant at least first period consumption. Therefore, considering B the parameter for the time preference, the problem would be:
max U=ln(C1) + Bln(C2)
s.t: L = I + C1
Y(I) = L(1+r) + C2
with Probability P(I)
or
s.t: L = I + C1
with probability 1 - P(I)
My question is, Have you ever seen something like this? If yes, how to proceed? What is more important, I really need a bibliography (a book or article talking about this)
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103.1. Nizar was computing a Statistics problem asking for the probability of Event A. His answer was 1.36 Using your
...
36 Using your knowledge of probability, why should Nizar have known that his answer was NOT correct and gone back to review his calculations?
2. A four-colored spinner was spun 80 times. The spinner landed on green 15 times, yellow 30 times, blue 10 times, and red 25. Based on this data, what is the experimental probability of the spinner landing on green? (Write your answer as a fraction in lowest terms.)
3. If the probability that a certain mechanical part in your new car will fail this year is 0.05, what is the probability that the mechanical part will not fail this first year?
4. A coin is loaded so that the probability of getting tails is 1/4. If the coin is flipped twice, what is the probability of getting tails twice?
5.If a 6-sided die is tossed and then a coin is flipped, what is the probability that an odd number is rolled and the coin lands on heads?
6.A field goal kicker makes 3 of every 7 attempts at a field goal. If he kicks 4 field goals in a certain game, what is the probability that he'll make all four? (Write your answer as a fraction in lowest terms.)
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104.
Value: 1
equation image indicator
a. (x - 2)2(x - 3)2
b. (x2+ 4)(x2+ 9)
c. (x - 2)(x +
...
2)(x - 3)(x + 3)
d. (x2 - 4)(x2+ 9)
Value: 1
The table below shows the cost of purchasing a standard stapler at five office supply stores, A through E. If the median cost of purchasing a standard stapler for these stores was $17.99, which of the following could NOT have been the cost of the stapler for Store A?
staplergraph.jpg
a. $19.95
b. $18.95
c. $16.95
d. $19.25
Value: 1
If equation image indicator then x =
a. 7
b. 1/5
c. 5
d. 1/7
Value: 1
A six−sided die, with sides numbered 1,2, 3,4,5, and 6, is tossed. What is the probability of tossing a number less than three?
a. 1/3
b. 0
c. 1/2
d. 1/4
Value: 1
If 6m + 4 = 8m, then 4m =
a. 6
b. 2
c. 8
d. 4
Value: 1
In the xy-plane, what is the y-intercept of the graph of the equation equation image indicator?
a. 2
b. 4
c. 16
d. There is no y-intercept.
Value: 1
Which of the following equations has both 2 and −4 as solutions?
a. x2 + 6x + 8 = 0
b. x2 - 2x - 8 = 0
c. x2 + 2x - 8 = 0
d. x2 - 2x + 8 = 0
Value: 1
The perimeter of a square is 20 ft. If you increase the length of the square by 2 feet and decrease the width by 1 foot, what is the area, in square feet, of the new figure?
a. 22
b. 28
c. 35
d. 40
Value: 1
(3x-2y4)-3 =
a. equation image indicator
b. equation image indicator
c. equation image indicator
d. equation image indicator
Value: 1
A softball is tossed into the air upward from a first floor balcony. The distance of the ball above the ground at any time is given by the function, distance function.png, where h(t) is the height of the softball above the ground (in feet) and t is the time (in seconds). What was the maximum height, in feet, of the softball above the ground after it was thrown?
a. 28
b. 30
c. 32
d. 34
Value: 1
A group of 100 people, some students and some faculty, attended a museum opening. Each student paid $10 per person for entrance to the museum and each of the faculty paid $25 per person for entrance. If the total paid, for all 100 people, was $1300, how many students attended the museum opening?
a. 20
b. 50
c. 70
d. 80
Value: 1
The ratio of Sam's age to Hank's age is 5 to 3. If the sum of their ages is 24, how old is Hank?
a. 21
b. 15
c. 19
d. 9
Value: 1
In the xy−coordinate plane shown below, point P has coordinates (8, −6). Which of the following is an equation of the line that contains points O and P?
O and P graph.jpg
a. equation image indicator
b. equation image indicator
c. equation image indicator
d. equation image indicator
Value: 1
The variables x and y are inversely proportional, and y = 2 when x = 3. What is the value of y when x = 9?
a. 54
b. 6
c. 2/3
d. 3/2
Value: 1
A farmer has 1235 trees to be planted on a rectangular parcel of land. If there are 24 trees planted in each row and each row must be complete before it is planted, how many trees will be left over after planting?
a. 21
b. 11
c. 0
d. 55
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108. When to balance dice are rolled, there are 36 possible outcomes. Find the probability that the sum is
...
is a multiple of three or greater than eight.
A certain game consist of rolling a single fair die and pays off as follows nine dollars for a six, six dollars for a five, one dollar for four and no payoffs otherwise.Find the expected winnings for this game.
A fair die is rolled four times. A 6 is considered success While all other outcomes are failures find the probability of three successes.
A pet store has nine puppies including 4 poodles 3 terriers and 2 retrievers. If Rebecca an errand in that order each select one puppy at random without replacement find the probability that Aaron select a retriever given that from last Rebecca selects a poodle.
Experience shows that a ski lodge will be for (166 guests) if there is a heavy snowfall in December, well only partially full (52 guests) With a light snowfall. What is the expected number of guests if the probability for a heavy snowfall is 0.40? I assume that heavy snowfall and light snowfall are the only two possibilities.
A pet store has six puppies Including two poodles two Terriers and to retrievers. If Rebecca and Aaron in that order each select one puppy random with replacement (They both may select the same one) Find the probability That Rebecca selects a terrier and Aaron selects a retriever.
Three married couples arrange themselves randomly in six consecutive seats in a row. Determine (A) the number of ways the following event can occur, And (B) the probability of the event. (The denominator of the probability fraction will be 6!=720, The total number of ways to arrange six items ). Each man was that immediately to the right of his wife.
A coin is tossed five times. Find the probability that all our heads. Find the probability that at least three are heads.
A certain prescription drug is known to produce undesirable facts and 35% of all patients due to drug. Among a random sample of a patient using a drug find the probability of the stated event. Exactly 5 have undesired effects.
10,000 raffle tickets are sold. One first prize of 1600, for second prizes of 800 each, And 9/3 prizes of 300 each or to be awarded with all winners selected randomly. If you purchase one ticket what are your expected winnings.
Suppose a charitable organization decides to Raise money by raffling A trip worth 500. If 3000 tickets are sold at one dollar each find the expected net winnings for a person who buys one ticket. Round to the nearest cent
Three men and seven women are waiting to be interviewed for jobs. If they are selected in random order find the probability that all men will be interviewed first
A fair diet is rolled. What is the probability of rolling on our number or a number less than three.
The pet store has 15 puppies, including five poodles, five Terriers, and five retrievers. If Rebecca and Aaron, in that order, select one puppy at random without replacement, find the probability that both select a poodle
Beth is taking a nine question multiple-choice test for which each question Has three answer choices, only one of which is correct. Beth decides on answering By rolling a fair die And making the first answer choice if the die shows one or two, The second If the die shows three or four, and the third if the die shows five or six. Find the probability of the stated event. Exactly 6 correct answers
For the experiment of drawing a single card from a standard 52 card deck find (a) the probability and (b) the odds are in favor that they do not drive six
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110.Question 1: suppose the dealer has an an Ace showing, you have a 3 and an 8 in your hand,
...
r player at the table is showing a 5 and 6. Compute the expected value of a one-dollar insurance bet under these circumstances
Question 2: Suppose that( perhaps after being hit one or more times) you have cards addings up to 18. Using the table provided in these notes, compute the probability that you will lose, and the probability that you will tie.
Question 3: The "Royal Hand" consists of King and Queens of the same suit. Compute the probability of being dealt a Royal Hand in the first two cards.
Question 4: Compute the probability that you will initially be dealt two cards adding up to exactly 20. ( First think about how many ways two cards can up to 20 in blackjack.)
Question 5: You have two 9s in your hand. The dealer is showing a 7, and the only other player at the table is sowing a King and a 9. If you ask to be hit, what is the probability that you will bust on the next card?
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112.1. The amount of chilli sauce dispensed from a machine at a local food joint is normally distributed with a
...
with a mean of 25 gm and a standard deviation of 5 gm.
(a) If the machine is used 500 times, approximately how many times will it be expected to dispense 30 gm or more of chilli sauce?
(b) How can you decrease this number to half? Give a numerical answer.
2. StarTech manufactures re sensors. They use a protective screen for their sensors to protect it from dust. The sensor becomes useless if the thickness of the screen exceeds 0.5 mm. They outsource the production of the screen to a di erent company that claims to manufacture screens with a mean thickness of 0.3 mm and a standard deviation of 0.1 mm.
(a) If 10000 screens are manufactured how many will be discarded because they are too thick?
(b) If screens less than 0.2 mm are too thin to be used, what is the probability that screens manufactured by the above company will be discarded because they are too thick or too thin? Show the result on a graph.
3. The amount of time that Sam spends playing the guitar is normally distributed with a mean of 15 hours and a standard deviation of 3 hours.
(a) Find the probability that he spends between 15 and 18 hours playing the guitar during a given week.
(b) What is the probability that he spends less than 3 hours playing the guitar during a given week?
4. Soon after he took oce in 1963, President Johnson was approved by 160 out of a sample of 200 Americans. With growing disillusionment over his Vietnam policy, by 1968 he was approved by only 70 out of a sample of 200 Americans.
(a) What is the 90% con dence interval for the percentage of all Americans who approved of Johnson in 1963? In 1968?
(b) What is the 90% con dence interval for the change?
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