You are a researcher tasked with conducting an observational cross-sectional study that will examine the prevalence of food insecurity among Stanford students. Food security will be measured as a categorical variable with three levels: not insecure, insecure, very insecure. You will also gather data on age, students' income, gender, class rank, and weight.

a) Describe how you would collect data for this observational cross-sectional study. Explain how observational cross-sectional study differs from an experimental study?

b) Will your data collection strategy yield sample or population data? Explain the difference between sample and population data and why one or the other will be more suitable for your study?

C) What are the dependent and independent variables in this study?

1. Trying to improve the techniques I use in the classroom and reduce the anxiety of the students, I decided to try an experiment. I decided that I would incorporate more relaxation techniques prior to exams. For a comparison, I subjected the students to twice the exams (evil, I know). In essence, I did a pre- and post-test. The scores are below. At α = 0.05, can it be concluded that the relaxation techniques helped improve test scores?

(For each of the problems you must state: the hypotheses and identify the claim, state the test value, p-value, make a decision and summarize the results.)

A study investigated if cell phone use impacted student drivers' reaction times. There were two groups: 29 students were assigned to the cell phone group while 29 students were assigned to the control group. The experiment measured the response time to traffic lights; for the cell phone group, the mean was 585.1 with a standard deviation of 88 and for the control group, the mean was 540 with a standard deviation of 65. Construct a 90% confidence interval for the difference in mean response times between the cell phone and control groups. Point Estimate: = Margin of Error: E = (round to 4 decimal places) Lower Limit: (round to 4 decimal places) Upper Limit: (round to 4 decimal places) We are 90 % confident that the true is between and .

In Faroe island, a sports training camp provides 3 different sections: one in Squash, one in Football, and one in Basketball. These sections are open to any of the 100 people in the camp. There are 28 students in the Squash section, 26 in the Football section, and 16 in the Basketball section. There are 12 students that are in both Squash and Football, 4 that are in both Squash and Basketball, and 6 are in both Football and Basketball. In addition, there are 2 people taking all 3 sections. If a person chosen at random;

a) If a person chosen at random, the probability that he is not playing in any of these sports sections is

b) If a person chosen at random, the probability that he is playing exactly one sports section is

c) When two people are chosen randomly, the probability that at least 1 is playing in a sports section is

Assignment 1
Choose any one variable of interest (e.g., cups of coffee) and collect data from two independent samples (e.g., men vs. women, children vs. adults, college students vs. non-college students, etc.) could make up the data.. of minimum size n=5 each. Complete the following:

1. Indicate whether your variable is continuous or discrete.
2. Indicate which scale of measurement your variable is categorized as (nominal, ordinal, interval, or ratio).
3. Calculate the mean, median, and mode for each sample.
4. Provide a conclusion sentence that describes the difference between these two samples based on the two means (e.g., “the sample of men consume more coffee on average compared to the sample of women”).

Students of a large university spend an average of $7 a day on lunch. The standard deviation of the expenditure is $2. A simple random sample of 25 students is taken. What is the probability that the sample mean will be at least $4? Jason spent $15 on his lunch. Explain, in terms of standard deviation, why his expenditure is not usual. Explain what information is given on a z table. For example, if a student calculated a z value of 2.77, what is the four-digit number on the z table that corresponds with that value? What exactly is that 4-digit number telling us? Explain why we use z formulas. Why don't we just leave the data alone? Why do we convert? must show work

IN C++

Write a program that prompts the user to enter the number of students and each student’s name and score, and finally displays the student with the highest score (display the student’s name and score). Also calculate the average score and indicate by how much the highest score differs from the average. Use a while loop.

Sample Output

Please enter the number of students:

4

Enter the student name:

Ben Simmons

Enter the score:

70

Enter the student name:

Carson Wentz

Enter the score:

80

Enter the student name:

Joel Embiid

Enter the score:

90

Enter the student name:

Bryce Harper

Enter the score:

75

Joel Embiid

score is 90

the average is 78.75

the difference is 11.25

Press any key to continue . . .

The students are trying to access videos where each video is of size 850,000 bits and the average request rate from the students to Blackboard servers is 16 requests/second. Assume that the RTT to any of the Blackboard servers from the Internet router is on average 3 seconds and that the total average response time is the sum of the average access delay and the average Internet delay. Also assume that for the average access delay, the average time required to send an object over the access link (α) and the arrival rate of objects to the access link (β) follow the relation α/ (1−αβ) .

(a) Find the total average response time.

(b) Find the total response time when a cache is installed in the institutional LAN with miss rate of 0.4.

MUST BE DONE IN C (NOT C++)

In this program we will calculate the average of x students’ grades (grades will be stored in an array). To do so, please follow these guidelines:

- Your program should ask the user for the number of students that are in the class. This number should help you declare your array.

- Use the function seen in class to scan the grades of the array. In other words, we will populate the array with a function.

- When done, use the printing function seen in class to make sure all grades were scanned correctly.

- Then, call the “average” function. This function will receive two parameters, the array’s length and the array. Inside the function, you will calculate the average (using a loop) and you will return the average.

- In main, you will received this returned value and print it.

What are the advantages and drawbacks of universities using social media to communication with stakeholders -- students, potential students, alumni, donors, etc?

Do you think there are more or fewer communication barriers when using social media?

Be thorough in your answer. What should managers do to be sure they communicate effectively when using social media?

Looking at the rules and regulations that universities are establishing, do you think that business organizations shoud have rules for employees using social media?

What types of rules do you think you be necessary?

What have been your experiences -- both positive and negative -- with social media. From your experiences, what guidelines could you suggest for managers and organizations?