Really do not understand any of the concepts behind the following problem:

Bicycling World, a magazine devoted to cycling, reviews hundreds of bicycles throughout the year. Its Road-Race category contains reviews of bicycles used by riders primarily interested in racing. One of the most important factors in selecting a bicycle for racing is its weight. The following data show the weight (pounds) and price ($) for ten racing bicycles reviewed by the magazine.

a). Develop a scatter chart with weight as the independent variable. What does the scatter chart indicate about the relationship between the weight and price of these bicycles?

b). Fit a regression line into the data. What is the estimated regression model represented by the regression line?

c). Create a regression model output in Excel at 0.05 level of significance. Are the regression parameters b₀ and b₁ equal to zero? Is there a significant relationship between Weight and Price for the bicycles? Explain your answer.

d). How much of the variation in the prices of the bicycles in the sample does the regression model you estimated in part (b) explain?

e). The manufacturers of the D’Onofrio Pro plan to introduce the 15.5 pounds D’Onofrio Elite bicycle later this year. Use the regression model you estimated to predict the price of the D’Onofrio Elite bicycle. Show your working.

f). Create a scatter plot of residual versus x-variable. From this scatter plot, could the estimated regression model obtained from the bicycle sample data be used to make a statistical inference? Explain how your plot of residual versus x-variable indicate whether or not the regression assumptions for statistical inference are met.

A magazine tested LCD televisions. The table below shows the overall quality score and cost in hundreds of dollars. Use the rank correlation coefficient to test for a correlation between the two variables. Use a significance level of a=0.05.Based on these​ results, can you expect to get higher quality by purchasing a more expensive LCD​ television?

Determine the null and alternative hypotheses for this test.

Determine the correlation coefficient.

1.) A leading magazine (like Barron's) reported at one time that the average number of weeks an individual is unemployed is 29.8 weeks. Assume that for the population of all unemployed individuals the population mean length of unemployment is 29.8 weeks and that the population standard deviation is 5.9 weeks. Suppose you would like to select a random sample of 194 unemployed individuals for a follow-up study.

Find the probability that a single randomly selected value is between 29.1 and 30.2.
P(29.1<x<30.2)= ___?

Find the probability that a sample of size n=194n=194 is randomly selected with a mean between 29.1 and 30.2.
P(29.1<¯x<30.2)= ___?

2.) Scores for a common standardized college aptitude test are normally distributed with a mean of 500 and a standard deviation of 98. Randomly selected men are given a Test Prepartion Course before taking this test. Assume, for sake of argument, that the test has no effect.

If 1 of the men is randomly selected, find the probability that his score is at least 583.3.
P( xx > 583.3) =  

If 5 of the men are randomly selected, find the probability that their mean score is at least 583.3.
P( ¯xx¯ > 583.3) =  

To better understand how husbands and wives feel about their finances, a magazine conducted a national poll of 1,017 married adults age 25 and older with household incomes of $50,000 or more. Consider the following example set of responses to the question "Who is better at getting deals?"

(a)

Develop a joint probability table and use it to answer the following questions. (Round your answers to four decimal places.)

(b)

According to the marginal probabilities, what is the most likely response?

I ammy spouse    we are equal

(c)

Given that the respondent is a husband, what is the probability that he feels he is better at getting deals than his wife? (Round your answer to four decimal places.)

(d)

Given that the respondent is a wife, what is the probability that she feels she is better at getting deals than her husband? (Round your answer to four decimal places.)

(e)

Given a response "My spouse" is better at getting deals, what is the probability that the response came from a husband? (Round your answer to four decimal places.)

(f)

Given a response "We are equal," what is the probability that the response came from a husband?

What is the probability that the response came from a wife?

1. A student is considering publishing a new magazine aimed directly at owners of Japanese automobiles. He wanted to estimate the fraction of cars in the United States that are made in Japan. The computer output below summarizes the results of a random sample of 50 autos.  

z-interval for proportion

With 90.00% confidence

0.29938661 < p(japan) < 0.46984416

1. Interpret the computer output.
2. Explain what “90% confidence” means.

c. A politician urging consumers to purchase products manufactured in the United States says, “Half of all cars in the United States are made in Japan.” Does your confidence interval support or contradict this statement? Explain

Question:

1.Find an example of reported statistical data on the internet, newspaper or magazine. it should include data that was collected from sampling.

2.give the link of the website

Paragraph 1: Summarize the article and data collected. Indicate any techniques used to collect the data, the sample and population. Please be aware that your article may not include all of this information. You may have to speculate how the data was collected and what the sample and population are. Alternatively you may have to simply indicate that the information was not provided.            

Paragraph 2: Summarize the pros or positive aspects of the article concentrating on statistical aspects and the presentation of any data. You may comment on any graphs or tables if they are provided.

Paragraph 3: Summarize the cons or negative aspects of the article concentrating on statistical aspects and the presentation of any data. You may comment on any graphs or tables if they are provided.

Paragraph 4: Give your overall opinion of the article concentrating on the statistical aspects.

3. A parenting magazine reports that the mean number of phone calls that teenage girls make per
night is at least four (4). For a science fair project, a student sets out to prove the magazine
wrong. The student claims that the average number of phone calls that teenage girls in their
area make is less than four. The student collects information from a simple random sample
of 25 teenage girls from their high school, and calculates a mean of 3.4 calls per night with a
sample standard deviation of 0.9 calls per night. Test the student’s claim at the 0.01 level of
significance.
(a) (3 points) State the null and alternative hypotheses H0 and Ha.
(b) (2 points) Identify which distribution to use for the test statistic. If applicable, calculate
the number df of degrees of freedom; if not applicable, then say so.
(c) (2 points) Compute the value of the test statistic z, t, or χ
2
.
(d) (2 points) Compute the p-value associated to the test statistic.
(e) (1 point) Choose whether or not to reject the null hypothesis H0.

4. (3 points) A new whitening toothpaste advertises that it whitens teeth up to three shades
whiter. The product has been so successful that the company wants to change its slogan to say
“more than three shades whiter”. Before changing the slogan, the company’s executives want
to test this new claim with an hypothesis test. According to the sample that they obtained,
the decision is to reject the null hypothesis. If, in reality, the mean number of shades that the
toothpaste whitens teeth is three shades whiter, was an error made in the hypothesis testing
process? If so, of which type?

2. A leading consumer magazine, The False Traders, claims that the small coffee sold at PHILZ coffee shop does not contain 12 ounces of coffee. A sample of 25 customers who purchased a small coffee yielded the following information:

- a sample mean of 12.10 ounces and a sample standard deviation of 0.25 ounces.

(5)        a. Set up a 95% confidence interval for the true population mean.

(10)      b. At the 10% level, test the alternate hypothesis that the true mean is not equal to 12 ounces.

3. The table below lists pitches in a baseball game for two pitchers and the breakdown of “strikes” and “balls” (good pitches and bad pitches). The summary statistics are also listed.

  Bumgarner                  Cueto

            Sample Mean (pitches per inning) 12.0                              13.0

            Sample Variance (pitches per inning) 3.5 8

            Sample Size (# of innings) 9 9

             (an “inning” is one of the rounds in a game)

(5)        a. At the 99% level, test the alternate hypothesis that Cueto throws more pitches per inning than Bumgarner for the entire season (population of pitches):

(5)        b. Set up a 90% confidence interval for the true difference in the proportion of Balls thrown by each pitcher for the entire season:

(5)        c. Perform a hypothesis test to see if the proportion of throwing strikes for Bumgarner and Cueto is not equal for the entire season. Set the Type I error equal to 10%.

3. A leading consumer magazine, The False Traders, claims that the small coffee sold at PHILZ coffee shop does not contain 12 ounces of coffee. A sample of 16 customers who purchased a large coffee yielded the following information:

- a sample mean equal to 11.4 ounces and a sample standard deviation of 0.16 ounces.

a. What formula would you use to set up a 90% confidence interval for the true population mean?

b. What t-value would you use to set up a 90% confidence interval for the true population mean?

(10)     b.  At the 10% level, test the hypothesis whether the true mean is less than 12 ounces.