Can someone explain a,b and c? The answers are correct I believe but I just need a more clear explenation on the formulas and final answers

If 2 cards are drawn from a well-shuffled deck of 52 playing cards, what are the probabilities of getting

Answer:

Total no of ways of drawing 2 cards from a well-shuffled deck of 52 playing cards = ⁵²C₂ = 1326

(a)        two spades;

Number of ways getting 2 spades / total number of ways = (¹³C₂)/1326 = 78/1326 = 0.0588

(b)        two aces;

Number of ways getting 2 aces / total number of ways = (⁴C₂)/1326 = 4/1326 = 0.003

(c)        a king and a queen?

            13*13/1326 = 0.12745

A psychologist is interested in the conditions that affect the number of dreams per month that people report in which they are alone. We will assume that based on extensive previous research, it is known that in the general population the number of such dreams per month follows a normal curve, with μ= Unknown node type: span and σ=4 . The researcher wants to test the prediction that the number of such dreams will be greater among people who have recently experienced a traumatic event. Thus, the psychologist studies 36 individuals who have recently experienced a traumatic event, having them keep a record of their dreams for a month. Their mean number of alone dreams is 8. Should you conclude that people who have recently had a traumatic experience have a significantly different number of dreams in which they are alone? (a) Carry out a Z test using the five steps of hypothesis testing (use the .05 level). (b) Make a drawing of the distributions involved. (c) Explain your answer to a person who has never had a course in statistics. (d) ADVANCED TOPIC: Figure the 95% confidence interval.

1. The association between the variables "dollars earned" and "hours worked" for a worker at store would be

QUESTION 2

The association between the variables "GPA" and "hours spent studying" for a student would usually be

QUESTION 3

The association between the variables "cost of a book" and "the buyers body temperature" would be

QUESTION 4

The association between the variables "airfare" and "distance to destination" would be

QUESTION 5

A graph that will help to one to see what type of curve might best fit the bivariate data

QUESTION 6

If the correlation coefficient for a linear regression is -0.932. there is sufficient evidence that a linear relationship exists between the x and y data

QUESTION 7

Which of the following correlation coefficients represents the most linear function?

QUESTION 8

If the correlation coefficient for linear regression is 0.25. there is sufficient evidence that a linear relationship exists between the x and y data

QUESTION 9

A data point that lies statistically far from the regression line is a potential

QUESTION 10

1. correlation5:
   
   If the correlation coefficient is 0.90, the value of the coefficient of determination would be

QUESTION 11

Use your TI83 to determine the correlation coefficient of the following set of points. Round correctly to the nearest hundredth.

(4, 4), (-2, -7), (3, 3), (4, -1)

QUESTION 12

Use your TI83 to determine the correlation coefficient of the following set of points. Round correctly to the nearest hundredth.

(4, 4), (-2, -4), (7, -2), (4, 1)

QUESTION 13

Use your TI83 to determine the correlation coefficient of the following set of points. Round correctly to the nearest hundredth.

(2, 4), (1, -1), (2, 2), (5, -4)

As a part of a new healthcare reform, hospitals must report incidence of specific demographic and health care outcomes to maintain funding. Within this report, it was found that 23.3% the Medicare population in Westmoreland county is Diabetic. As part of a random survey to determine if current preventative measures are helping to target this, a random sample of 50 individuals within the Medicare population we sampled.

Let X be the number of individuals who are Diabetic.

1. Can X be considered a binomially distributed random variable? Why?

2. Identify n and p for this problem.

3. Can variables X be well-approximated by normal random variables?

4. What is the expected number of diabetic individuals for this problem?

5. What is the variance for the number of diabetic individuals for this problem?

6. How many combinations are possible that consists of exactly 20 people that are diabetic?

7. What is the probability of observing 20 diabetic individuals?

Describe how simple linear regression analysis and multiple regression are used to support areas of industry research, academic research, and scientific research.

1. A sample of eight resistors of a certain type resulted as follows:

                  43, 46, 42, 38, 40, 46, 49, 40

Compute the following:

1. Sample Mean
2. Sample Variance
3. Sample Median
4. 25% Percentile
5. 75% Percentile

2. Consider the following pdf:

      P(X = 0) = 0.48, P(X = 1) = 0.39, P(X = 2) = 0.12, and P(X = 3) = 0.01.

Find the following:

• Do the plot for P(X) and F(X)
• F(0) = P(X ≤ 0) =
• F(1) = P(X ≤ 1) =
• F(2) = P(X ≤ 2) =
• F(3) = P(X ≤ 3) =
• P(1 ≤ X ≤ 2) =
• μ_x =
• σ_x² =

7 people are selected for a survey. Each person is asked about - their opinion on candidate C (Favor or Oppose), and - their political affiliation (Democratic, Independent, or Republican). How many outcomes are in the event that at least one of the 7 people is independent?

Consider a sample with data values of 26, 24, 23, 18, 31, 35, 29, and 24. Compute the range, interquartile range, variance, and standard deviation

Suppose we have data from a health survey conducted in year 2000. Data were obtained from a random sample of 1000 persons.

An OLS linear regression analysis was carried out in the following way:

Dependent Variable: Systolic blood pressure (SBP, in mmHg)

Independent Variables: Gender (1 if female, 0 if male)

Age (in years)

Education (binary variables for “Not graduated from high school” and “Graduated from high school (but not from college)”; the reference category is “Graduated from college”)

A part of the results is shown below. The column labeled “Beta” show estimated values of partial regression coefficients. (It can be interpreted that beta’s for the reference categories, “Male” and “Graduated from college”, are fixed to be zero.) The p-values are for the two-sided test.

1. According to the results of this regression analysis, how much expected difference in systolic blood pressure (in mmHg) is estimated:

1-1. between the two education categories, “Not graduated from high school” and “Graduated from college”, controlling for gender and age (i.e., among those who have the same gender and at the same age)?

1-2. between males and females, controlling for age and education?

2. Suppose we change the reference category of education from “Graduated from college” to “Graduated from high school” and do the same regression analysis again.

What will be the value of partial regression coefficient (beta) for “Not graduated from high school”?

(Hint: The expected SBP differences among the education categories do not change.)

Choose a population that you would plan to sample or survey. Your discussion board thread title should be "Sampling from ______". Some ideas for populations to take a sample from:

Mesa students

San Diego community college students

All San Diego college students

Adults in San Diego

Starbucks customers

Your choice!

Describe an perfect scenario sampling method: Describe in your own words one of the sampling methods learned in class and how it could be applied to your population - in this case, you can assume you will have access to things like a list of everyone living in San Diego.

Describe a realistic sampling method. Being that you don't actually have a list of all San Diego residents (or similar for your population), how would YOU go about trying to get a representative sample? No need to use any fancy terms or definitions here, just describe how you'd collect data from 100 people for your sample.

What are some limitations that will arise with your realistic scenario? Are there groups that might be left out?

Answer all of this in Approximately 150-200 words in length and well-written.

You manage an ice cream factory that makes two flavors: Creamy Vanilla and Continental Mocha. Into each quart of Creamy Vanilla go 2 eggs and 3 cups of cream. Into each quart of Continental Mocha go 1 egg and 3 cups of cream. You have in stock 500 eggs and 900 cups of cream. You make a profit of $3 on each quart of Creamy Vanilla and $2 on each quart of Continental Mocha. How many quarts of each flavor should you make to earn the largest profit?

In a lottery 5 different numbers are chosen from the first 90 positive integers.

(a) How many possible outcomes are there? (An outcome is an unordered sample of five numbers.)

(b) How many outcomes are there with the number 1 appearing among the five chosen numbers?

(c) How many outcomes are there with two numbers below 50 and three numbers above 60?

(d) How many outcomes are there with the property that the last digits of all five numbers are different? (The last digit of 5 is 5 and the last digit of 34 is 4.)

In an article in the Journal of Management, Joseph Martocchio studied and estimated the costs of employee absences. Assume an infinite population. The mean amount of paid time lost during a three-month period was 1.0 day per employee with a standard deviation of 1.4 days. The mean amount of unpaid time lost during a three month period was 1.2 days per employee with a standard deviation of 1.6 days. Suppose we randomly select a sample of 100 blue-collar workers.

1. What is the probability that the average amount of paid time lost during a three-month period for the 100 blue-collar workers will exceed 1.5 days?

2. What is the probability that the average amount of unpaid time lost during a three-month period for the 100 blue-collar workers will be between 1.4 and 1.5 days? Please give a precise explanation, as if you are telling someone who doesn’t know anything about statistics, for the reasoning behind your answer?

3. How large a random sample is needed to construct a 95 percent confidence interval for the mean for population paid time lost with a margin of error equal to 0.1? Please give a precise explanation, as if you are telling someone who doesn't know anything about statistics for the reasoning behind your answer.

) A researcher recruited 2100 men in his research and followed up every year for 4 years to find out the incidence rate of respiratory disease.

After 1 year, there was not a new diagnosis of respiratory disease, and 100 lost to follow up,

After 2 years, found one new case of respiratory disease and 99 lost to follow up,

After 3 years, found 7 new cases of respiratory diseases and seven hundred ninety three lost to follow up.

After 4 years, found eight new cases of respiratory diseases and three hundred ninety two lost to follow up.

Calculate the incidence rate of respiratory disease

(**new cases of respiratory disease and men lost to follow up were disease-free for six months) ** and contribute ½ years to the denominator)

As reported in "Runner's World" magazine, the times of the finishers in the New York City 10 km run are normally distributed with a mean of 61 minutes and a standard deviation of 9 minutes. Let x denote finishing time for the finishers.

a) The distribution of the variable x has mean____ and standard deviation____ .

b) The distribution of the standardized variable z has mean____ and standard deviation____ .

c) The percentage of finishers with times between 60 and 80 minutes is equal to the area under the standard normal curve between____ and____ .

d) The percentage of finishers with times exceeding 86 minutes is equal to the area under the standard normal curve that lies to the____ of____ .