The following data represents number of pictures an individual has posted on Facebook (X) and their level of narcissism(Y) as measured on a 10-point scale, 10 being highest.

Analyze this data using both the correlational method as well as regression via StatsCrunch. Write the data up using APA guidelines in MS Word. Submit both your output from StatsCrunch as well as your Word document

3) In a study of student loan subsidies, I surveyed 100 students. In this sample, students will owe a mean of $25,000 at the time of graduation with a standard deviation of $2,000.

(a) Develop a 96% confidence interval for the population mean.

(b) Develop a 96% confidence interval for the population standard deviation.

The random variable X can be used to describe the voltage at the receiver in a modem. If symbol 0 is transmitted, X follows a Gaussian distribution centered at −5V with a standard deviation of 2V , or X ∼ n(x; −5, 2). If symbol 1 is transmitted, X follows a Gaussian distribution centered at +5V with a standard deviation of 2V , or X ∼ n(x; 5, 2). Assume that symbols 0 and 1 are equally likely to be sent.

(a)in matlab Plot the PDF of X. (hint: f(x) vs. x in volts, you need to use the law of total probability).

(b)in matlab Plot the CDF of X.

In a packing plant, a machine packs cartons with jars. It is supposed that a new machine will pack faster on the average than the machine currently used. To test that hypothesis, the times it takes each machine to pack 10 cartons are recorded. It is given that the mean time for the new machine is 42.14 seconds with a standard deviation of 0.683 seconds. The mean time for the old machine is 43.23 seconds with a standard deviation of 0.750 seconds.

What are the observational units?

What is the variable being measured?

Is the variable categorical or quantitative?

Which scenario would you use to analyze these data? Select one: a. Two proportion b. One means (matched pairs) c. One means d. One proportion e. Two mean

You may not use a theory-based test on these data since the validity requirements are not met. Select one: True False

Discuss the uses of data mining in finance with examples in detail?

Part II. Indicate whether you would perform a z test, two-sample t test, paired t test, or ANOVA for the following research question? All the outcomes are continuous variables.  

1. A group of adolescent boys was offered interpersonal skills counseling and then tested in September and May to see if there was any impact on family harmony.
2. 3 groups of participants were exposed to different levels of treatment for ankle sprain. Which treatment was more effective?
3. 1 group of men was provided access to an exercise program and tested two times over a 6-month period for heart health.
4. The principal at a school claims that the students in his school are above average intelligence. A random sample of 30 students’ IQ scores have a mean score of 112.5. Is there sufficient evidence to support the principal’s claim?

a sociologist claims the probability that a person picked at andom in times square new york city is visiting the area is 0.83. you think this sounds high and want to see if the balue is actually less then 0.83. you asked 50 people selected at random in times square where they are from and found 37 people who were visiting. perform the hypothesis test using a=0.05 What type of hypothesis test do you use? What is the test statistic and it’s value? What is the p value? What is your verdict? What is the reason for your verdict? At the _____ level of significance, from the sample data, there____ is/isn’t sufficient evidence to conclude that_____

Dean Parmalee wished to know if the year-end grades assigned to Wright State University Medical School students are predictive of their second-year medical board scores. The following table shows, for 89 students, the year-end score (AVG, in percent of 100) and the score on the second year medical board (BOARD) examination (data: medscores.mtw).

a) Create scatterplots of BOARD vs. AVG. Assess the nature of the relationship of these variables.

2. Give the estimates of the coefficients of your model.

3. Interpret the Estimated intercept and slope?

4. What is the value of R-square? Interpret it.

5. Are there any outliers or influential observations?

6. Give the predicted BOARD score for an individual with an 85 average. Interpret it.

7. Assess the fit of the model and interpret.

8. Explain why this model is not appropriate for someone with AVG value of 60.0.

9. Use the regression model to give 95% mean and individual prediction intervals for AVG score of 95.73 and 94.03. Make a graph showing the 95% confidence bands for the mean and the 95% prediction intervals.

type in will be best：）

1- Three forces act on a point: 3 N at 0°, 4 N at 90°, and 5 N at 217°.

a. What is the net force? b. What fourth force will put the point in equilibrium?

2- A 100 kg wooden crate rests on a wooden ramp with an adjustable angle of

inclination.

a. Draw a free body diagram of the crate. b. If the angle of the ramp is set to 10°, determine...

i. the component of the crate's weight that is perpendicular to the

ramp ii. the component of the crate's weight that is parallel to the ramp iii. the normal force between the crate and the ramp iv. the static friction force between the crate and the ramp

v. At what angle will the crate just begin to slip?

A company has discovered that a recent batch of batteries had manufacturing​ flaws, and has issued a recall. In a group of 15 batteries covered by the​ recall, 3 are dead. Two batteries at random are chosen from the package of 15

​b) Create a probability model for the number of good batteries chosen.

​c) What's the expected number of good​ batteries?

​d) What's the standard​ deviation?

Sleep: Assume the general population gets an average of 7 hours of sleep per night. You randomly select 45 college students and survey them on their sleep habits. From this sample, the mean number of hours of sleep is found to be 6.89 hours with a standard deviation of 0.25 hours. You claim that college students get less sleep than the general population. That is, you claim the mean number of hours of sleep for all college students is less than 7 hours. Test this claim at the 0.01 significance level.

(a) What type of test is this?

-This is a two-tailed test.

-This is a left-tailed test.    

-This is a right-tailed test.

(b) What is the test statistic? Round your answer to 2 decimal places.
t- _{x =}

(c) Use software to get the P-value of the test statistic. Round to 4 decimal places.
P-value =

(d) What is the conclusion regarding the null hypothesis?

-reject H₀

-fail to reject H₀    

(e) Choose the appropriate concluding statement.

-The data supports the claim that college students get less sleep than the general population.

-There is not enough data to support the claim that college students get less sleep than the general population.     

-We reject the claim that college students get less sleep than the general population.

-We have proven that college students get less sleep than the general population.

The following times series shows the demand for a particular product over the past 10 months. Month Value

1 324

2 311

3 303

4 314

5 323

6 313

7 302

8 315

9 312

10 326

a. Use α = 0.2 to compute the exponential smoothing values for the time series. Compute MSE, MAPE and a forecast for month 11.

b. Calculate MSE and MAPE for three month moving average ?

c. Compare the three-month moving average forecast with the exponential smoothing forecast using α = 0.2. Which appears to provide the better forecast based on MSE?

9) In a sample of 400 people selected randomly from one town, it is found that 130 of them are Gamecock Fans. At the 0.05 significance level, test the claim that the proportion of all people in the town who are Gamecock fans is 27%.

A] What type of statistical test can be used here?

a. Z-test of proportions            c. F Test                                e. Either c² or λ Test

b. a-Test of proportions           d. Either T or F-Test               f. T-Test

         ➔       

B] What is the stated claim about the proportion?

a. p = 0.27 The population proportion is the same as 27%.

b. p ≠ 0.27 The population proportion is different from 27%.

c. p > 0.27 The population proportion is greater than 27%.

d. p < 0.27 The population proportion is less than 27%.

e. p ≥ 0.27 The population proportion is greater than or equal to 27%.

f. p ≤ 0.27 The population proportion is less than or equal to 27%.

          ➔       

C] What are the null hypothesis (H₀) and the alternative hypothesis (H_a)? Circle one answer out of the “a” through “f” choices below.

                                    a. H₀: p > 0.27                           d. H_a: p < 0.27  

H_a:p ≤ 0.27                                     H₀: p ≥ 0.27

b. H₀: p = 0.27                           e. H_a: p = 0.27  

H_a: p ≠ 0.27                                   H₀: p ≠ 0.27

c. H_a: p > 0.27                            f. H₀: p < 0.27  

H₀: p ≤ 0.27                    H_a: p ≥ 0.27

                                                                                                                  ➔       

(9 continued)

D] Is this test:       a. Fat tailed?                          d. Inverse tailed?

b. Two tailed?                        e. Left tailed?

c. Right tailed?                       f. Meta-tailed?

          ➔       

E] What is the numerical value of the test statistic (TS) calculated from the observed data?

a. 0.5558          b. 2.4777     c. 1.9600     d. 2.0917     e. 0.6456     f. 0.6234

               ➔       

F] Provide EITHER the Critical Value (CV) OR the p-value

Critical Value (CV):

a. z = 2.05       b. z = 1.643 c. z = 1.96 d. z = 1.645         e. z = 2.576           f. z = 2.03

       ➔       

P-value:

a. 0.4210         b. 0.6830     c. 0.0132   d. 0.5321            e. 0.6283              f. 0.5221

       ➔       

G] For this problem about Gamecock fans, what is your decision about H₀ (the null hypothesis)?

a. Fail to reject the claim         c. Fail to reject H₀                   e. Accept H₀        

b. Reject H₀                           d. Reject the claim         f. Accept the claim

          ➔       

(9 continued)

H] For this problem about Gamecock fans, what is the decision about the original claim?

a. At the 5% level, there is NOT enough evidence to reject the claim that the proportion is 27%.

b. At the 10% level, there is enough evidence to reject the claim that the proportion is 27%.

c. At the 5% level, there is enough evidence to reject the claim that the proportion is 27%.

d. At the 10% level, there is NOT enough evidence to reject the claim that the proportion is 27%.

e. At the 5% level, there is enough evidence to support the claim that the proportion is 27%.

f. At the 10% level, there is enough evidence to support the claim that the proportion is 27%.

➔       

Parts are inspected on a production line for a defect. It is known that 5% of the pieces have this defect. (this applies to 5 parts of the problem)

to. If an inspector examines 12 parts, what is the probability of finding more than 2 defective parts? (10 pts)

b. What is the expected number of defective parts in 12-piece sample? (10 pts)

c. In another area, parts are inspected until 5 defective parts are found, then the machine is stopped to reset the machine. On average, how many pieces does the machine stop? (10 pts)

d. In another area, parts are inspected until 3 faulty parts are found, then the machine is stopped to reset the machine. What is the probability of needing between 55 and 60 pieces to stop the machine? (10 pts)

and. 100 pieces were separated for special tests. A sample of 15 pieces will be taken from these 100. What is the probability of finding at least 2 defects in the sample? (15 points)

Given two independent random samples with the following results:

n1=11 x‾1=174 s1=34   n2=8 x‾2=191 s2=22

Use this data to find the 90% confidence interval for the true difference between the population means. Assume that the population variances are equal and that the two populations are normally distributed.

Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.

Find the standard error of the sampling distribution to be used in constructing the confidence interval. Round your answer to the nearest whole number.

Construct the 90%90% confidence interval. Round your answers to the nearest whole number.