Here are the summary statistics for randomly selected weights of newborn girls: n=237, mean=33.8 hg, and s=6.2 hg. Construct a confidence interval estimate of the mean. Use a 90% confidence level

Describe a situation where you would use ANOVA by stating 1. the quantity of populations that are to be investigated, 2 a quantitative variable on these populations, 3 the sizes of samples from these populations, 4 your null hypothesis, 5 your alternative hypothesis, and 6 a significance level. Then find 7 the degree of freedom of the numerator of your F- statistic, 8 the degree of freedom of the denominator of your F- statistic, and state 9 what the P- value for your test statistic being less than your significance level would imply. Remember that you do not need to list the values of the variable for individuals in either the samples or the population, and that the values for 3 and 6 not need to be calculated, only stated

21. Teaching Methods A new method of teaching reading is being tested
on third grade students. A group of third grade students is taught using
the new curriculum. A control group of third grade students is taught
using the old curriculum. The reading test scores for the two groups are
shown in the back-to-back stem-and-leaf plot.
Old Curriculum New Curriculum

9 3
9 9 4 3
9 8 8 4 3 3 2 1 5 2 4
7 6 4 2 2 1 0 0 6 0 1 1 4 7 7 7 7 7 8 9 9
7 0 1 1 2 3 3 4 9
8 2 4

Key: 9 0 4 0 3 = 49 for old curriculum and 43 for new curriculum
At a = 0.10, is there enough evidence to support the claim that the new
method of teaching reading produces higher reading test scores than the
old method does? Assume the population variances are equal.

Are there any significant association between students’ spatial reasoning ability and verbal ability? Note: Verbal ability scores are the ranks.
(Use Data A)

1. Compute the statistic needed to answer the research question. Tip: Use Spearman rho and make a decision.

Research Question 3: Are there any significant association between students’ mathematics achievement and science achievement controlling for verbal ability? Use Data B.

1. Compute the statistic needed to answer the research question. [2 pt]

Data B. Intercorrelation Among Variables

The accuracy of a census report on a city in southern California was questioned by some government officials. A random sample of 1215 people living in the city was used to check the report, and the results are shown below.

Using a 1% level of significance, test the claim that the census distribution and the sample distribution agree.

(a) What is the level of significance?


State the null and alternate hypotheses.

H₀: The distributions are the same.
H₁: The distributions are different.H₀: The distributions are different.
H₁: The distributions are different.    H₀: The distributions are the same.
H₁: The distributions are the same.H₀: The distributions are different.
H₁: The distributions are the same.

(b) Find the value of the chi-square statistic for the sample. (Round the expected frequencies to at least three decimal places. Round the test statistic to three decimal places.)


Are all the expected frequencies greater than 5?

YesNo    

What sampling distribution will you use?

uniformnormal    binomialchi-squareStudent's t

What are the degrees of freedom?


(c) Estimate the P-value of the sample test statistic.

P-value > 0.1000.050 < P-value < 0.100    0.025 < P-value < 0.0500.010 < P-value < 0.0250.005 < P-value < 0.010P-value < 0.005

(d) Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis that the population fits the specified distribution of categories?

Since the P-value > α, we fail to reject the null hypothesis.Since the P-value > α, we reject the null hypothesis.    Since the P-value ≤ α, we reject the null hypothesis.Since the P-value ≤ α, we fail to reject the null hypothesis.

(e) Interpret your conclusion in the context of the application.

At the 1% level of significance, the evidence is sufficient to conclude that census distribution and the ethnic origin distribution of city residents are different.At the 1% level of significance, the evidence is insufficient to conclude that census distribution and the ethnic origin distribution of city residents are different.    

Anystate Auto Insurance Company took a random sample of 386 insurance claims paid out during a 1-year period. The average claim paid was $1585. Assume σ = $256.

Find a 0.90 confidence interval for the mean claim payment. (Round your answers to two decimal places.)

lower limit $

upper limit $

Find a 0.99 confidence interval for the mean claim payment. (Round your answers to two decimal places.)

lower limit $

upper limit $

please explain how to get the z score using the table. I can not figure it out.

please do not use excel. I am trying to learn how to do this.

Complete parts, given Σx = 372, Σy = 113, Σx² = 24814, Σy² = 3371, Σxy = 8371, and r ≈ 0.926.

a) Verify the given sums Σx, Σy, Σx², Σy², Σxy, and the value of the sample correlation coefficient r. (Round your value for r to three decimal places.)

b) Find x, and y. Then find the equation of the least-squares line  = a + bx. (Round your answers for x and y to two decimal places. Round your answers for a and b to three decimal places.)

c) Find the value of the coefficient of determination r². What percentage of the variation in y can be explained by the corresponding variation in x and the least-squares line? What percentage is unexplained? (Round your answer for r² to three decimal places. Round your answers for the percentages to one decimal place.)

d) Predict the percentage of all fatal accidents due to failing to yield the right of way for 70-year-olds. (Round your answer to two decimal places.)
_____ %

The owner of two​ fast-food restaurants has recorded customer satisfaction ratings for both locations on a scale of 1 to 5 ​(5 =Most ​satisfied). The table linked below summarizes the data.

a. Calculate the mean satisfaction rating at each location.

b. Calculate the standard deviation of each distribution.

c. What conclusions can be drawn from these​ results?

Here is where you solve below

a.

*What is the mean for Restaurant​ A?

​(Type an integer or decimal rounded to three decimal places as​ needed.)

W*hat is the mean for restaurant B?

​(Type an integer or decimal rounded to three decimal places as​ needed.)

b.

*What is the standard deviation for restaurant​ A?

​(Type an integer or decimal rounded to three decimal places as​ needed.)

What is the standard deviation for restaurant B?

​(Type an integer or decimal rounded to three decimal places as​ needed.)

c. What conclusions can be drawn from these​ results?

(choose the correct answer)

* Restaurant A has lower / higher average customer satisfaction ratings than the ones in Restaurant B. Customer satisfaction ratings for Restaurant A are less / more consistent when compared with ones in Restaurant B.

In a study of household recycling practices, 30 randomly selected households had their recycling output measured in both pounds of paper waste and pounds of plastic waste. The StatCrunch data set for this question contains the two measurements for each household. Use the data to construct a 95% confidence interval estimate of the difference between the mean weight of paper waste for a household and its mean weight of plastic waste. Use paper waste as Sample 1. Round each of your answers to three decimal places; add trailing zeros as needed. The 95% confidence interval estimate is lb < µ1 - µ2 < lb.

Paper    Plastic

15.09   9.11   ""
6.98   2.65   ""
12.32   11.17   ""
11.42   12.81   ""
12.73   14.83   ""
13.61   8.95   ""
11.36   10.25   ""
5.86   3.91   ""
9.19   3.74   ""
14.33   6.43   ""
6.44   8.4   ""
6.67   6.09   ""
3.27   0.63   ""
16.08   14.36   ""
7.72   3.86   ""
7.98   6.09   ""
9.55   9.2   ""
9.45   3.02   ""
6.38   8.82   ""
6.05   2.73   ""
9.41   3.36   ""
6.33   3.86   ""
20.12   18.35   ""
16.39   9.7   ""
6.96   7.6   ""
13.31   19.7   ""
11.08   12.47   ""
2.41   1.13   ""
8.82   11.89   ""
12.43   8.57   ""

A physical trainer has four workouts that he recommends for his clients. The workouts have been designed so that the average maximum heart rate achieved is the same for each workout. To test this design he randomly selects twenty people and randomly assigns five of them to use each of the workouts. During each workout, he measures the maximum heart rate in beats per minute with the following results. Can the physical trainer conclude that there is a difference among the average maximum heart rates which are achieved during the four workouts?

Step 1 of 2:

Find the value of the test statistic to test for a difference between the workouts. Round your answer to two decimal places, if necessary.

Step 2 of 2:

Make the decision to reject or fail to reject the null hypothesis that equal average maximum heart rates are achieved by the four workouts and state the conclusion in terms of the original problem. Use α=0.05α=0.05.

Suppose that 26 of 200 tires of brand A failed to last 30,000 miles whereas the corresponding figures for 200 tires of brands B, C, and D were 23, 15, and 32. Test the null hypothesis that the failure rates of the four tire brands are 10% at the 0.05 level of significance.

A report states that adults 18- to 24- years-old send and receive 128 texts every day. Suppose we take a sample of 25- to 34- year-olds to see if their mean number of daily texts differs from the mean for 18- to 24- year-olds.

(a)

State the null and alternative hypotheses we should use to test whether the population mean daily number of texts for 25- to 34-year-olds differs from the population daily mean number of texts for 18- to 24-year-olds. (Enter != for ≠ as needed.)

H₀:

H_a:

   Your answer cannot be understood or graded. More Information

(b)

Suppose a sample of thirty 25- to 34-year-olds showed a sample mean of 118.7 texts per day. Assume a population standard deviation of 33.17 texts per day.

Compute the p-value. (Round your answer to four decimal places.)

p-value =

(c)

With

α = 0.05

as the level of significance, what is your conclusion?

Reject H₀. We cannot conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.Do not reject H₀. We cannot conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.     Reject H₀. We can conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.Do not reject H₀. We can conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.

(d)

Repeat the preceding hypothesis test using the critical value approach.

State the null and alternative hypotheses. (Enter != for ≠ as needed.)

H₀:

128

H_a:

Find the value of the test statistic. (Round your answer to two decimal places.)

State the critical values for the rejection rule. (Use α = 0.05. Round your answer to two decimal places. If the test is one-tailed, enter NONE for the unused tail.)

test statistic ≤ test statistic ≥

State your conclusion.

Reject H₀. We cannot conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.Do not reject H₀. We cannot conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.     Reject H₀. We can conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.Do not reject H₀. We can conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds.

When hypothesis testing, when might you use a related sample versus an independent sample? Provide examples of both population to illustrate the differences.

Consider the following hypothesis test.

A sample of 40 provided a sample mean of 26.4. The population standard deviation is 6.

(a)

Find the value of the test statistic. (Round your answer to two decimal places.)

(b)

Find the p-value. (Round your answer to four decimal places.)

p-value =

(c)

At

α = 0.01,

state your conclusion.

Reject H₀. There is sufficient evidence to conclude that μ > 25.Reject H₀. There is insufficient evidence to conclude that μ > 25.      Do not reject H₀. There is sufficient evidence to conclude that μ > 25.Do not reject H₀. There is insufficient evidence to conclude that μ > 25.

(d)

State the critical values for the rejection rule. (Round your answer to two decimal places. If the test is one-tailed, enter NONE for the unused tail.)

test statistic ≤test statistic ≥

State your conclusion.

Reject H₀. There is sufficient evidence to conclude that μ > 25.Reject H₀. There is insufficient evidence to conclude that μ > 25.      Do not reject H₀. There is sufficient evidence to conclude that μ > 25.Do not reject H₀. There is insufficient evidence to conclude that μ > 25.

A survey of 300 hospital workers is taken. The question asked is "Do you think that staffing is adequate at your hospital, yes or no?" Perform the Chi-square test to determine if the frequency of no responses is statistically larger than the frequency of yes responses. The following responses were received: yes - 120, no - 180.