In 2017, 965 students registered for a course. Explain how you will use the random number table to select a simple random sample of 20 students.
Start from digit one of row 6.


Fill in the blanks
1. Bar chart is normally used for ___________ data.
2. Pie chart presents ___________ data.
3. A ____________________ is used to describe the relationship between two categorical variables.
4. A ___________ histogram is one with a single peak.
5. A ___________ histogram is one with two peaks.
6. Observations measured at the same point in time across individual units are called _______________ data.
7. Observations measured at successive points in time on a single unit are called _______________ data.

Students are to observe two or more adults unknown to the observer. The student must not be able to hear the subjects being observed and those being observed must not be wearing a uniform of any kind as this would provide information about their occupation to the observer. Students must describe the environment and the people being observed, i.e., age, gender, dress, etc. Discuss the nonverbal communication, i.e. eye contact, body position and any other nonverbal behavior. Provide your interpretation of the relationship between those being observed. Be very discrete and do not have a conversation with those being observed. minimum 400 words and if you could provide academic articles references 2.

a. Is the t-test the appropriate test for this study?

b. yes, state why, using examples to support your agreement or if no, state why not, using examples to support your disagreement

An independent sample t-test would be used if a professor at FIU wanted to compare his calculus classes scores from the past two semesters. Class 1 had 20 students and an average of 70 and SD of 15. Class 2 had 25 students and an average of 74 standard deviation of 25. You have to use alpha .05 to determine if class 1 and 2 had a difference between scores by using the degrees of freedom on a normal distribution table.

A professor has kept track of test scores for students who have attended every class and for students who have missed one or more classes. below are scores collected so far.

perfect: 80,86,85,84,81,92,77,87,82,90,79,82,72,88,82

missed 1+:61,80,65,64,74,78,62,73,58,72,67,71,70,71,66

1. Evaluate the assumptions of normality and homoscedasticity

2. conduct a statistical test to assess if exam scores are different between perfect attenders and those who have missed class

3. What is the meaning of the 95% confidence interval given from the R code. What does the 95% CI explain compared to the hypothesis test and how does the 95% CI relate to the test statistic and p value

Q1. Jamie wants to forecast the number of students who will enroll in operations management next semester in order to determine how many sections to schedule. He has accumulated the following enrollment data for the past six semesters:

a (2 pts). Compute a three-semester moving average forecast for semesters 4 through 7 (Model a) (Use two decimals).

In Python:

def _nodeAtIndex(self, index):
"""Returns the reference to the node at the given index;
If index is out of range, raise IndexError
"""
# PROBLEM 2
# You can assume that index is non-negative.
# You need to traverse the list and stop at the required index.
# YOUR CODE HERE
(THIS IS WHAT I HAVE CURRENTLY WRITTEN BUT I"M STUCK AND DON"T KNOW WHAT TO DO)

while current != None: # use a while-loop.
plist.append(current._element) # process the stored element.
count = 0 #Will give us the index of current node
if (count == index):
return (plist)
  
raise IndexError('The index is out of range')

Down below is the following code that give's more detail about the code. If you have any question's or need any more info, please don't hesitate to ask.

class SLinkedList:
"""Singly linked list with access to front and end, and with stored size.
"""

#-------------------------- nested _Node class --------------------------
class _Node:
__slots__ = '_element', '_next' # streamline memory usage

def __init__(self, element, next):
self._element = element
self._next = next

#------------------------------- queue methods -------------------------------
def __init__(self):
"""Create an empty list."""
self._head = None
self._tail = None
self._size = 0

def __len__(self):
"""Return the number of elements in the list."""
return self._size

def isEmpty(self):
"""Return True if the list is empty."""
return self._size == 0
  
# READ THIS!
def __repr__(self):
plist = []
current = self._head
# This is how to traverse a list:
while current != None: # use a while-loop.
plist.append(current._element) # process the stored element.
current = current._next # jump to the next node.
return "SLinkedList(%s)" % repr(plist)

def first(self):
"""Return but do not remove the first element.
Raise EmptyError if the list is empty.
"""
if self.isEmpty():
raise EmptyError('The SLinkedList is empty')
return self._head._element
  
def deleteFirst(self):
"""Remove and return the first element.
Raise EmptyError if the list is empty.
"""
if self.isEmpty():
raise EmptyError('The SLinkedList is empty')
answer = self._head._element
self._head = self._head._next
self._size -= 1
if self.isEmpty(): # special case when list is empty
self._tail = None # removed head had been the tail
return answer
  
def addFirst(self, e):
"""Add element e to the front of the list."""
self._head = self._Node(e, self._head) # create and link a new node
if self._tail == None: # special case when list was empty
self._tail = self._head # added head is the tail
self._size += 1
  
def addLast(self, e):
"""Add e to the end of the list."""
newest = self._Node(e, None) # node will be new tail node
if self.isEmpty():
self._head = newest # special case: previously empty
else:
self._tail._next = newest
self._tail = newest # update reference to tail node
self._size += 1
  

1. A large insurance company wants to determine whether the proportion of male policyholders who would not submit auto insurance claims of under $500 is the same as the proportion of female policyholders who do not submit claims of under $500. A random sample of 400 male policyholders produced 272 who had not submitted claims of under $500, whereas a random sample of 300 female policyholders produced 183 who had not submitted claims of under $500

a) Construct a 90% confidence interval for the difference between the proportions of males and of females who had not submitted auto insurance claims of under $500.

b) Find the p-value of the appropriate test.

In a random sample of 10 LAS students, the sample mean time spent studying during a particular week was 15.7 hours with sample standard deviation 3.1 hours. In a random sample of 8 Engineering students, the sample mean time studying during the same week was 20.2 hours per month with sample standard deviation 4.4 hours. Assume that the two populations are normally distributed.

a) Assume that the two population variances are equal. Construct a 95% confidence interval for the difference between the overall average times Engineering and LAS students spent studying during this week.

b) Since the larger sample variance is more than twice as big as the smaller one, the assumption of equal variances is questionable here. Construct a 95% confidence interval for the difference between the overall average times Engineering and LAS students spent studying during this week without assuming that the two population variances are equal. Use Welch’s T.

1. Minorities in Higher Education

You are a social psychologist interested in the adjustment of international students who go to school at American universities. You decide to examine whether there are differences in scores on the Acceptability by Others Scale (AOS). The AOS is a scale that ranges from 1 to 20 (1 = feeling completely isolated – 20 feeling completely accepted) that measures acceptance within the college community. You collect scores on the AOS from a sample of international students (Int) at a small college in the United States and another sample of United States (U.S.) citizens attending the same college. The data is provided below. Conduct a two-tailed independent-samples t-test by hand using an alpha level of .05 to determine whether there are differences in AOS scores between the two samples. Record your answers below.

1. Step #1: A priori expectations
   1. Question of interest:

2. Prediction:

2. Step #2: Set up hypotheses
   1. H₀:

2. H₁:

3. Step #3: Set criteria for decision
   1. t_cv (critical value for rejecting the null hypothesis)

2. Decision rule for when to reject the null hypothesis:

4. Step #4: Collect data/ compute statistic

5. 
   Step #5: Report results in standard format – Must include test statistic , degrees of freedom, p-value , 95% confidence interval (95% C.I.) and conclusion (reject or fail to reject H₀)

​​​​​​​6. Step #6: Interpret the results of the statistical test in terms of the research question

1. Minorities in Higher Education

You are a social psychologist interested in the adjustment of international students who go to school at American universities. You decide to examine whether there are differences in scores on the Acceptability by Others Scale (AOS). The AOS is a scale that ranges from 1 to 20 (1 = feeling completely isolated – 20 feeling completely accepted) that measures acceptance within the college community. You collect scores on the AOS from a sample of international students (Int) at a small college in the United States and another sample of United States (U.S.) citizens attending the same college. The data is provided below. Conduct a two-tailed independent-samples t-test by hand using an alpha level of .05 to determine whether there are differences in AOS scores between the two samples. Record your answers below.

1. Step #1: A priori expectations
   1. Question of interest:

2. Prediction:

2. Step #2: Set up hypotheses
   1. H₀:

2. H₁:

3. Step #3: Set criteria for decision
   1. t_cv (critical value for rejecting the null hypothesis)

2. Decision rule for when to reject the null hypothesis:

4. Step #4: Collect data/ compute statistic

5. 
   Step #5: Report results in standard format – Must include test statistic , degrees of freedom, p-value , 95% confidence interval (95% C.I.) and conclusion (reject or fail to reject H₀)

​​​​​​​6. Step #6: Interpret the results of the statistical test in terms of the research question

(Survey from 9.41: In a survey of 446 students, it was found that 50% of the sampled students lived on campus and 50% lived off campus.)

In the same survey used in 9.41, 88% of the sampled students were right-handed.

a. The proportion of all people who are right-handed is said to be 0.88. Tell the value of standardized sample proportion z, if we want to test whether the proportion of all students who are right- handed could be 0.88.

b. If we sketch a normal curve for the distribution of sample proportion (centered at 0.88), what portion should be shaded to indicate the area represented by the P-value for testing against the alternative that population proportion is less than 0.88? [Please see the three graphs on p. 000 for examples of P-value as a shaded area.]

c. What portion of the standard normal (z) curve should be shaded to indicate the area represented by the P-value for testing against the alternative that the population proportion is less than 0.88? What does the P-value equal in this case?

d. What portion of the normal curve for the distribution of sample proportion (again, centered at 0.88) should be shaded to indicate the area represented by the P-value for testing against the (two-sided) alternative that population proportion does not equal 0.88? What does the P-value equal in this case?

e. What portion of the normal curve for the distribution of standardized sample proportion z should be shaded to indicate the area represented by the P-value for testing against the (two-sided) alternative that population proportion does not equal 0.88?

f. Will the null hypothesis be rejected against either the one-sided or two-sided alternative? Explain.