1. Define variability.

2. What are the strengths and limitations of the range?

3. When computing a standard deviation, why are the deviations from the mean squared?

4. Why is the square root taken when computing the standard deviation?

5. What are the three measures of variability? Which is the most commonly used?

6. Compute the range of the following student’s test scores: 39, 64.5, 54, 49, 56, 61, 58

7. The local B League baseball team is trying out new pitchers. The new pitcher will be selected based on the mean velocity of his best pitches, but also based on the standard deviation of his pitches.   Compute the standard deviation and variance for Pitcher A if S(X-M)2 = 128, for 33 attempts (n). See formula - p.49

8. A school psychologist is interested in the variability of student IQ scores. What is the standard deviation of the following IQ scores? The scores are 100, 115, 85, 125, 75, 95, 105.

9. Here is a set of cognitive ability scores: 103, 112, 97, 126, 100, 131. Comprehensively assess variability (range, standard deviation and variance).

10. The length of time it takes to fly from one place to another varies based on many factors. Given the following flight lengths, compute the average flight time, the range and the standard deviation in flight lengths. The flight lengths from Kansas City to Los Angeles are: 1 hr 40 min, 1 hr 45 min, 3 hr, 3 hr 35 min, 3 hr 20 min, 1 hr 45 min, 3 hr 15 min, 3 hr 25 min. Change all flight times to minutes.

11. Here is a set of adaptive functioning scores: 97, 122, 105, 140, 94, 129. Assess variability (range, standard deviation and variance).

12. Using the procedure explained on page 4383 of your text to find the range, variance and standard deviation of prej from chapter 2 data set 1 using SPSS.

Alicia, a 16-year-old high school student, was diagnosed with anorexia nervosa 2 years ago. Over those 2 years, she has required multiple hospital admissions for dehydration, malnutrition, and electrolyte imbalance. During these hospitalizations, it was established that Alicia has a history of self-starving and also exercising excessively to reduce her weight to less than 75% of her normal weight. According to her mother Joan, Alicia has always been “harder on herself than anyone should be.” She has always been an overachiever who is dissatisfied with anything less than perfect. Joan says that unlike her other children, Alicia is “wound very tight, almost obsessive, and has to do everything herself.”

                  Last week, Alicia was hospitalized again after she fainted during gym class. Since her admission, she has worked with a psychotherapist to identify some healthier coping strategies and behaviors. The therapist suggested that Alicia sign a contract, agreeing that she will follow certain agreed-upon behaviors. Now that she is about to be released from the hospital, an advanced practice nurse, Eileen, is brought in to plan her after-care. The first thing Eileen suggests is that she and Alicia create a contract.

Alicia is frustrated. “Another contract?” she says. “This is so stupid! I already did a contract in the hospital! Why should I have to start over again?”

“You’re not starting over,” Eileen says. “This is a new contract for a new phase of your ongoing wellness plan.”

“All this controlling structure,” Alicia says. “I feel like I’m being babied.” She sits back in her chair, looking miserable.

1. What sort of “contract” do you think Eileen wants Alicia to sign at this time? What would it include?

1. Alicia complains that having a contract is “controlling.” Do you think an eating contract is an effective treatment intervention for Alicia? Why or why not? Considering what you have read about Alicia’s personality, how might establishing a contract with her be particularly valuable?

choose the correct words to complete the sentences.

Part A: Academic Vocabulary

1. Doctors need to be able to communicate quickly with patients who experience anxiety/probability/tendencies between appointments.

2. There is an irrational/apparent/anxious connection between patients' stress levels and wait time for doctors to provide them with test results.

3. The patients' appointments, phone calls, and stress are all probable/demonstrated/triggered by new symptoms or increased pain.

4. Patients' fears can seem irrational/logical/probable because there may not be a good reason to think they need immediate medical attention.

5. From the patient's point of view, the logic/triggered/demonstrated thing to do might be to contact the doctor and make sure everything is fine.

6. Since many patients have a probability/tendency/trigger to worry about medical issues, doctors have begun to use social media such as blogging to help patients outside of office hours.

7. Some doctors send mass email notifications of new blog posts to reduce the probability/anxiety/logic that patients will seek time-consuming answer to general questions

. 8. To help patients with anxiety, some doctors provide triggers/logic/demonstration of the anxiety-reducing techniques described in their posts and messages.

Part B: Academic Collocations

Complete the paragraph with the correct forms of the academic phrases in the box.

basic logic clearly demonstrate high probability

Irrational tendency    logical conclusion

There are several ways that parents can help children who are victims of cyberbullying. While................ would say that staying connected to bullies online is unhealthy, children might not realize this without their parents help. They can also monitor their children's Internet use and try to stop their ..........................to stay connected to bullies on social media. While some parents can help their children, research............................. that many teenagers need outside help, perhaps from a school counselor or psychologist. Without this help, there is a.............................that cyberbullying will continue. The...................is that the problem of cyberbullying needs to be prevented because it is doing so much harm to these young people.

The song Baby Shark has taken the world by storm, including Dr. Link's living room during his kids' daily dance parties. In the song, the melody of three notes, D (293.5 Hz), E (329.5 Hz), and G (392 Hz) are played repeatedly. Dr. Link decides to surprise his girls by learning to play it on his daughter' s Ukulele (a small guitar) but he needs your help. To play the note, Dr. Link needs to determine the tension in the G-string on the Ukulele. The nylon string on the Ukulele has total length 50 cm and total mass of 120 milligrams but only 34 cm of the string vibrates in its first harmonic.

a. Determine the tension in the G-string needed to play the G note.

b. Mrs Link wants to also learn how the play the song but on another identical Ukulele. When she plucks the G-string at the same time Dr. Link plucks his Ukulele string, it creates a beat frequency of 4 Hz. When she tightens the tension in the string, the beat frequency decreases. What is the original frequency of her Ukulele string?

c. Without tuning the Ukulele, Mrs. Link wants to know if it possible to play the D note. Please use the physics you know to explain if this is possible and if it is, tell her the length of the string that needs to vibrate. Recall that the longest the string can be that vibrates is the distance is 34 cm which is the unfingered length of the string.

d. If the G string somehow vibrated at its 5th harmonic, what would the wavelength of the standing wave?

If possible, could you write out the process of these problems? include a drawn normal distribution with shading please.

1. suppose X-N (4, 2) what value of x is 1.5 standard deviations to the left of the mean?
2. Suppose X-N (15,3) between what x values does 68.27% of the data lie? The range of x values is centered at the mean the distribution (i.e., 15)
3. X-N (54,8) find the probability that x>56

4. height and weight are two measurements used to track a child's development. The World Health Organization measures a child's development by comparing the weights of children who are the same height and same gender. In 2009 Weights For All 80cm girls in the reference population at a mean of 10.2 kg and a standard deviation of 0.8 kg. X-N (10.2, 0.8). Weights are normally distributed. calculate the Z scores that correspond to the following weights and interpret them.
a. 11 kg b. 7.9kg c. 12.2 kg

5. Facebook provides a variety of statistics on this website that detailed growth in popularity of the site. On average, 28% of 18 to 35 year olds check their Facebook profile before getting out of bed in the morning. Suppose this percentage follows a normal distribution with standard deviation of 5%. A. find the probability that the percent of 18 to 35 year olds to check Facebook before getting out of bed in the morning is at least 30. B. Find the 95th percentile and express it in a sentence.

1. Education Planning: Suppose you have just had your first child and you want to begin saving for their college education. You estimate that with inflation, the cost of four years of college at a top university will cost a total of $225,000 in 18 years when your child graduates from high school. How much do you need to invest at the end of each month (part a) or year (part b) for the next 18 years to accumulate the $225,000 assuming:

1. a 6% annual interest rate compounded monthly?

2. an 8% annual interest rate compounded annually?

List the appropriate post hoc test (or tests if more than one is suitable) for each scenario described:

• Weight gained by students dining at three different cafeterias over a six-month period
• Weight loss by students attending four different campus gym locations over a three-month period
• Planned comparisons of pre-med students’ average organic chemistry test scores across four different colleges, one of which is a state school, while the others are private schools
• Sleep quality measured in minutes, by students using two different types of pillows