Just tell me we will use two Sample independent test or the two sample dependent test.

An experiment was carried out to compare recall ability when reading electronically compared to hard copy. Thirty students from a first-year university English class agreed to participate. Each student was shown a randomly generated list of 40 five-letter words on a tablet and given 2 minutes to memorise them. They were then given 4 minutes to write down as many of the words as they could recall. An hour later, the students repeated the experiment but this time the list of 40 five-letter words was given to them on a piece of paper. In each case, the percentage of correctly recalled words was recorded. The aim is to see if there is a difference in the percentage of words correctly recalled between the electronic list and the paper list.

Scientists are interested in human recall and memory. Is it easier to memorize words that have "meaning"? To study this problem, two lists of 20 three-letter "words" were used. One list contained meaningful words (e.g., CAT, DOG), whereas the other list contained nonsense words (e.g., ATC, ODG). A ninth grade class of thirty students will be divided into two groups of students. One group was asked to memorize the list of meaningful words; the other group was asked to memorize the list of nonsense words. The number of words correctly recalled by each student was tabulated.

Number of meaningful words recalled: 12,15,12,12,10,3,7,11,9,14,9,10,9,5,13

Number of nonsense words recalled: 4,6,6,5,7,5,4,7,9,10,8,7,3,2

Is there convincing evidence to report that meaningful words are remembered better than nonsene words?

What statistic test would you use to prove that?

1. If someone has a calcium deficiency, how will that effect their muscle for generation? Why would it effect  

2. How does optimal length effect the cross bridges? What happens at greater the optimal length and what happens at less the optimal length?

Choose the study design that best fits the following description: A study was conducted to determine if the incidence of noise-induced hearing loss was greater in registered dental hygienists who used ultrasonic scaling devices for cumulative periods of time longer than two hours per day as compared to registered dental hygienists who used these devices for less than two hours daily or not at all. Annual amount of time using the scaling devices was ascertained at the start of the study. All of the participants were then contacted every year for a hearing exam.

a) Ecologic Study

b) Randomized Clinical Trial

) Prospective Cohort Study

d) Retrospective Cohort Study

e) Case Control Study

f) Cross Sectional Study

1. Prove by contraction that

   L = {0^x 1^y 0^x+y | x >= 1 and y >=1} is not Regular.

   Must use the Pumping Lemma.

[ HINT: Describe the language in English first. Use example 3 from the lecture notes ]

a) Choose one S from L where S is longer than N

      (Describe S in terms of N and M)

      S = **??**

b) List all places v can be in S: (i.e. all possible uvw mappings)

      (Note: v has to be in the first N chars)

      v has to be where?       ?**?

c) For each possible place for v in #2 above, is there is a way to repeat/skip v to make it

        go out of the language L?

• Where v is:                                   ?**?
• Repeat factor: i =                      ?**?
• What does u v^i w look like?    ?**?
• Is u v^i w in L?                               ?**?

   Thus, there was no way to break S into uvw and repeat or skip v

     as much as we want. We found a counter example S that does not satisfy Pumping Lemma.

d) Conclusion about L:    ?**?

In a sample of 4500 first year college students, a national survey reported that 39% participated in community service or volunteering work.

a)v Find the margin of error for99% confidence level. Explain the findings of the study to someone who does not know statistics.

b) Suppose a similar study collects a new sample of 4,500 first year students. If a 99% confidence interval is computed from the new sample, will the confidence interval will be exactly the same as the results in a)? Explain your answer.

c) The same survey also asked about academic life. In response to one of the questions, 42% of first students plan to study abroad. Give the 95% confidence interval for the population proportion.

Which samples do you think are non-biased samples of the population of all students at a college/four‐year university? If it is a biased sample, is there a different population for which you believe the sample could be considered a non-biased sample?

1. A random sample of 100 students from the registrar's student list
2. A random sample of 100 students in the library on a Thursday night
3. A random sample of 100 students in the student center on a Friday night
4. A random sample of 100 students at a basketball game on a Tuesday night
5. A random sample of 10 students from 10 randomly chosen dorms on campus
6. A random sample of 100 students from cars registered on campus

Of all freshman at a large college, 16% made the dean’s list in the current year. As part of a class project, students randomly sample 40 students and check if those students made the list. They repeat this 1000 times and build a distribution of sample proportions.

1. What is this distribution called?

2. Would you expect the shape of this distribution to be symmetric, right skewed, or left skewed? Explain your reasoning.

3 Find/calculate a measure of the variability of this distribution. 4. What is the formal name of the value that you computed in (c)?

5. Use the information above to construct a 95% confidence interval and interpret it using a full sentence.

6. What is the margin of error in your confidence interval? (Be sure to show a calculation to support your response.)

7. Suppose the students decide to sample again, this time collecting 90 students per sample. They build a new distribution of sample proportions. How will the variability of the new distribution compare to the variability of the distribution when each sample contained 40 observations.

In this exercise, you will create a basic data management system for students in the Department of Computer Science and Information Technology using the linked list.

You must write two classes – Student class attached, and StudentChart.

Student class consists of student data. StudentChart class contains a linked list of all students in the department.

For this purpose, you must fulfill the following interfaces (note - fields of the objects should be marked as private).

Class: Student chart

Class of Student Chart contains data for all students stored in a linked list. The way to add a student to the list by method addStudent only to the front of the list. At the beginning the student list is empty, the number of students enrolled in the Department is 0. Think what would be the fields of this class, so that you can know much information at any one time.

Constructors:

Methods:

It is recommended to write tester to present all the methods of the class and to check that they actually work.

The student class :

public class Student {
   private String name;// student name
   private long id; // student identity number
   private int [] grades = new int[5]; // list of student courses grades
   
   //costructor that initialize name and id
   public Student(String name, long id){
       String n = name.toUpperCase();
       name = name.replace(name.charAt(0), n.charAt(0));
       for(int i=0 ; i<name. length(); i++)
           if(name.charAt(i)==' ')
               name = name.replace(name.charAt(i+1), n.charAt(i+1));
       this.name = name;
       this.id=id;
       
   }
   
   //copy constructor
   public Student(Student st){
       this.name= st.name;
       this.id = st.id;
   }
   
   //return the student name
   public String getName(){
       return name;
   }
   //returns the student id number
   public long getId(){
       return id;
   }
   
   // returns the course grade accoring to parameter course(course number) 
   public int getGrade(int course){
       if(grades[course]== 0)
           return -1;
       return grades[course];
       
   }
   // set the name of student with parameter name
   public void setName(String name){
       String n = name.toUpperCase();
       name = name.replace(name.charAt(0), n.charAt(0));
       for(int i=0 ; i<name. length(); i++)
           if(name.charAt(i)==' ')
               name = name.replace(name.charAt(i+1), n.charAt(i+1));
       this.name = name;
       
   }
   
   //sets the student id with parameter id
   public void setId(long id){
       this.id = id;
   }
   //set the course grade with parameter grade 
   public void setGrade(int course, int grade){
       grades[course]= grade;
   }
    // set all the grades of the student from user
   public void setGrades(int [] g){
       for(int i=0; i< grades.length; i++)
           grades[i]=g[i];
            
   }
   //returns the student average in his course
   public double getAverage(){
       int sum= 0;
       int count =0;
       for(int i=0; i< grades.length; i++){
           if(grades[i]!=-1)
          sum=+ grades[i];
           count++;
       }
       return sum/count*1.0;// compute and return average
       
   }
   
   // takes a student object as a parameter and 
   // return true if it is the same as student parameter
   public boolean equals(Student student){
       if(student.id== this.id)
           return true;
       else
           return false;
   }
   //returns a string that represents the student object
   public String toString(){
       
       String [] g = new String[5];
       for(int i=0; i< grades.length; i++)
           if(grades[i]!= -1)
               g[i]= grades[i]+" ";
               else
               g[i]="no grade";
              
       String n1= "Name:"+ name+"\n"+ "ID:  "+ id +"\n"+ "Grades:"+"\n"+
               "Introduction to Programming - "+g[0] +"\n"+"Introduction to Management – "+g[1]+"\n"+
               "Data Structures – "+g[2]+"\n"+"Introduction to Economics – "+g[3]+"\n"+
               "Introduction to Mathematics – "+g[4];
       
       return n1;               
   }
    
}

How would you employ longitudinal data on fecundity, health and longevity in a large cohort of humans to test the antagonistic pleiotropy hypothesis of senescence? Specify your hypothesis and how you would test it in 200 words or less