Find quantitative data about something that you are interested in. Make sure to get data on at least 50 individuals. 50 football players height

a. You don’t need to collect the data yourself, but you do need to find out and explain how the data was collected.

b. In order to be useful, this sample needs to be representative of some population.

       i. What population is represented by your sample

  ii. Describe biases that may result from your sampling method.

2. Select a level of significance.

3. Describe your data:

a. What are your observational units?

b. What is the variable you’re interested in?

c. What is your sample size?

d. Create a dotplot or histogram or some kind of chart that lets you see the shape of your data, and discuss the shape and any interesting characteristics of your data.

4. Use the theory method to find a confidence interval for the population mean at the level of confidence appropriate to your selected level of significance.

a. Don’t forget to show how you can tell that your method is valid for your data.

5. Explain the relationship between your sample mean, your confidence interval, and the population mean.

6. Discuss the usefulness and limitations of your confidence interval.

A study was made of seat belt use among children who were involved in car crashes that caused them to be hospitalized. It was found that children not wearing any restraints had hospital stays with a mean of 7.37 days and a standard deviation of 1.50 days with an approximately normal distribution.

(a) Find the probability that their hospital stay is from 5 to 6 days, rounded to five decimal places.

(b) Find the probability that their hospital stay is greater than 6 days, rounded to five decimal places.

A study considered the question, "Are you a registered voter?" Accuracy of response was confirmed by a check of city voting records. Two methods of survey were used: a face-to-face interview and a telephone interview. A random sample of 94 people were asked the voter registration question face to face. Of those sampled, eighty respondents gave accurate answers (as verified by city records). Another random sample of 89 people were asked the same question during a telephone interview. Of those sampled, seventy-four respondents gave accurate answers. Assume the samples are representative of the general population.

(a) Categorize the problem below according to parameter being estimated, proportion p, mean μ, difference of means μ1 – μ2, or difference of proportions p1 – p2. Then solve the problem. μ1 – μ2 p μ p1 – p2

(b) Let p1 be the population proportion of all people who answer the voter registration question accurately during a face-to-face interview. Let p2 be the population proportion of all people who answer the question accurately during a telephone interview. Find a 90% confidence interval for p1 – p2. (Use 3 decimal places.) lower limit upper limit

(c) Does the interval contain numbers that are all positive? all negative? mixed? Comment on the meaning of the confidence interval in the context of this problem. At the 90% level, do you detect any difference in the proportion of accurate responses from face-to-face interviews compared with the proportion of accurate responses from telephone interviews? Because the interval contains only positive numbers, we can say that there is a higher proportion of accurate responses in face-to-face interviews.

Because the interval contains both positive and negative numbers, we can not say that there is a higher proportion of accurate responses in face-to-face interviews.

We can not make any conclusions using this confidence interval.

Because the interval contains only negative numbers, we can say that there is a higher proportion of accurate responses in telephone interviews.

a. Generate samples of size 25, 50, 100 from a normal distribution. Construct probability plots. Do this several times to get an idea of how probability plots behave when the underlying distribution is really normal.

b. Repeat part (a) for a chi-square distribution with 10 df

I am required to use the R statistical program and I do not understand how to use it to solve this problem. If you could please show me the R Stats needed to solve this in the program I would highly appreciate it. Thank you and stay safe!

Use the standard normal table to find the​ z-score that corresponds to the cumulative area 0.1635. If the area is not in the​ table, use the entry closest to the area. If the area is halfway between two​ entries, use the​ z-score halfway between the corresponding​ z-scores.

We want to know whether the proportion of U.S. children living in families with
combined incomes below the poverty line has changed in the last 20 years. In 2000 the
proportion of children living below the poverty line was 12%. Out of a recent random
sample of 90 children 9 were from families with combined incomes below the poverty
line. Use this information to answer the following.
The alternative hypothesis for the above would be
A. ☐μ = 12%
B. ☐μ ≠ 12%
C. ☐π= .12
D. ☐π < .10
E. ☐π ≠ .12
The two tailed .05 critical value for a test of the above would be
A. ☐+/- 1.96
B. ☐+/- 1.645
C. ☐+/- 1.987
D. ☐+/- 1.671
E. ☐none of the above
Calculate p  for use in the above problem situation (rounded to 3 decimal places)
A. ☐.02
B. ☐.10
C. ☐.034
D. ☐.001
E. ☐.095
Your sample proportion =
A. ☐9%
B. ☐.90
C. ☐.12
D. ☐.133
E. ☐.10
I know it doesn’t, but if we assume that your sample data yielded a test statistic=.99,
what would be the exact (use our normal curve table) two tailed p value of your
finding?
A. ☐.3389
B. ☐.1611
C. ☐.3222
D. ☐.05
E. ☐.6778
If you do not reject the null in the above problem, you would say
A. ☐The proportion of children living below the poverty line is still 12%
B. ☐The proportion of children living below the poverty line has gone down
C. ☐The proportion of children living below the poverty line has changed
D. ☐You cannot prove that the proportion of children living below the poverty line
Cohen’s has changed
E. ☐The proportion of children living below the poverty line has not changed at all
Suppose you rejected the null in a hypothesis test to determine if a medicine worked
better than a placebo in controlling symptoms of the common cold and reported
Cohen’s d=.01 That should tell you which of the following
A. ☐ The difference was not statistically significant
B. ☐ The difference was significant using alpha=.01
C. ☐The difference was significant, and the medicine made a big difference in
symptoms
D. ☐The difference was not significant using alpha=.01
E. ☐The difference was significant, but the medicine did not make a big difference
in symptoms.

We want to compare the weights of two independent groups of mice. Group 1 consists of 14 mice that were fed only cheese. Group 2 consists of 18 mice that were fed only walnuts. Group 1 information: sample mean x1-bar = 18 and sample standard deviation s1 = 4. Group 2 information: sample mean x2-bar = 15 and sample standard deviation s2 = 7. Perform a 2-sided hypothesis test of H0: mu1 = mu2 against H1: mu1 not equal to mu2. Do not assume the two samples share the same variance. Find the P-value. [Hint: the distribution you use will have 27 degrees of freedom.] Answer to three decimal places.

Statictics and Proability

In a data communication system, several messages
that arrive at a node are bundled into a packet before they are
transmitted over the network. Assume that the messages arrive at
the node according to a Poisson process with λ = 30 messages per
minute. Five messages are used to form a packet.
a. What is the mean time until a packet is formed, that is,
until five messages have arrived at the node?
b. What is the standard deviation of the time until a packet
is formed?

c. What is the probability that a packet is formed in less than
10 seconds?
d. What is the probability that a packet is formed in less than
5 seconds?

1. A researcher hypothesized that people who exercise regularly are not sick as often as people who don’t exercise regularly. She randomly selected a group of exercisers and a group of non-exercisers and recorded the number of sick days they took of work for one year.  The data are recorded below.  Is there support for her hypothesis, α = .05?

Non-exercisers            Exercisers

6          7                      3          5

8          12                    2

6          9                      8

9                                  4

1. Test the hypothesis using the 5-step procedure. (22 points)
2. Calculate the 95% confidence interval. (4 points)
3. Calculate and estimate the effect size. (4 points)
4. Assuming you expected a large effect size, what is the minimum number of participants per group you’d need to attain at least 80% power?  (2 points)
5. (Note: this is for T-test statistics in psychology)

Use the given degree of confidence and sample data to construct a confidence interval for the population mean μ .

Assume that the population has a normal distribution. The principal randomly selected six students to take an aptitude test. Their scores were: 72.3 87.0 82.6 86.1 84.5 74.8 Determine a 90 percent confidence interval for the mean score for all students.

a. 86.30 < μ < 76.13

b. 76.13 < μ < 86.30

c. 76.03 < μ < 86.40

d. 86.40 < μ < 76.03

All trucks traveling on Interstate 40 between Albuquerque and Amarillo are required to stop at a weigh station. Trucks arrive at the weigh station at a rate of 200 per 8-hour day, and the station can weigh, on the average, 220 trucks per day. a. Determine the average number of trucks waiting, the average time spent waiting and being weighed at the weigh station by each truck, and the average waiting time before being weighed for each truck. b. If the truck drivers find out they must remain at the weigh station longer than 15 minutes, on average, they will start taking a different route or traveling at night, thus depriving the state of taxes. The state of New Mexico estimates that it loses $10,000 in taxes per year for each extra minute trucks must remain at the weigh station. A new set of scales would have the same service capacity as the present set of scales, and it is assumed that arriving trucks would line up equally behind the two sets of scales. It would cost $50,000 per year to operate the new scales. Should the state install the new set of scales?

So for the question I have, is 50 people responded to a survey question regarding how many pets they currently owned. 5 people said 0, 5 said 1, 7 said 2, 5 said 3, 4 said 4, 3 said 5, 4 said 6, 2 said 7, 2 said 8, 1 said 9, 1 said 11, 1 said 14, 2 said 15, 1 said 18, 1 said 19, 2 said 21, 1 said 32, 1 said 24, and 1 said 27. leaving 10,12,13,16,17, 20, 22, 25,26 with no results.

How do i figure out this below?

Count?, Minimum?, Maximum?,1st Quartile? ,3rd Quartile? ,Median? ,Mean? ,Standard Deviation? ,Mode? ,Z Value for Minimum? .Z Value for Maximum? ,Range? Thank you

A drawer contains six bags numbered 1-6, respectively i contains i blue balls and 6 green balls. You roll a fair die and then pick a ball out of a bag with the number shown on the die. What is the probability the ball is blue?

Groups of dolphins were observed off the coast of Iceland near Keflavik in 1998. The data in the file dolphin_dat on the course website give the time of the day and the main activity of the group, whether travelling quickly, feeding, or socializing. The dolphin groups varied in size. Usually feeding or socializing groups were larger than travelling groups.

Source of data: Marianne Rasmussen, Department of Biology, University of Southern Denmark, Odense, Denmark.

Activity        Period  Groups
Travel  Morning  6
Feed    Morning 28
Social  Morning 38
Travel  Noon     6
Feed    Noon     4
Social  Noon     5
Travel  Afternoon       14
Feed    Afternoon        0
Social  Afternoon        9
Travel  Evening 13
Feed    Evening 56
Social  Evening 10

A) Find a 90% confidence interval for the difference between morning and evening for the proportion of dolphins feeding assuming that the data is a result of two simple random samples and that the samples for both time periods are independent of each other.

B) Does there appear to be a significant difference in the proportion of dolphins engaged in feeding between morning and evening? Conduct the appropriate test of significance and discuss your results.

The accompanying table contains data on the​ weight, in​ grams, of a sample of 50 tea bags produced during an​ eight-hour shift. Complete parts​ (a) through​ (d).

a. Is there evidence that the mean amount of tea per bag is different from 5.5 ​grams? (Use alphaαequals=0.10)

State the null and alternative hypotheses.

Upper H equals

5.55

Upper H ≠5.55

A). Determine the test statistic.

B). Find the p-value.

C). Construct a 90% confidence interval estimate of the population mean amount of tea per bag. Interpret this interval.

The 90% confidence interval is _ <= u <= _

Table:  

5.64
5.43
5.43
5.41
5.55
5.33
5.55
5.43
5.52
5.42
5.58
5.41
5.53
5.52
5.55
5.62
5.55
5.45
5.44
5.49
5.48
5.39
5.47
5.61
5.51
5.33
5.66
5.28
5.48
5.54
5.76
5.59
5.44
5.56
5.59
5.52
5.32
5.48
5.53
5.57
5.62
5.43
5.43
5.26
5.55
5.64
5.49
5.57
5.68
5.35