PSYC 354 Homework 1 – 6 Assignment Papers
Answer the following questions:
A clinical psychologist decides to study the effects of treatment type (cognitive behavioral, psychodynamic, and interpersonal) on depression symptoms. 1-a) What would the dependent variable be in this study? Answer 1-b) What would the independent variable be in this study? Answer 1-c) How many levels would the independent variable have? Answer
Question 2 (a-d) A psychologist reported the results of a study in which 200 female college students with OCD completed an anxiety symptoms scale with scores ranging from 0 to 30. On average, the female college students scored 17. Identify each of the following for this study. 2-a) Population Answer 2-b) Sample Answer 2-c) Dependent variable Answer 2-d) Descriptive statistic Answer
Questions 3-6 Answer these general SPSS questions. 3) In which window do you enter data in SPSS? PSYC 354 Homework 1 – 6 Assignment Papers Answer 4) Which window displays the results of your analysis in SPSS? Answer 5) Which SPSS main menu would you use to choose a particular statistical test? Answer 6) In the Data View, each _____ represents one participant’s information. Answer
Question 7a-7b Suppose you have a data set in which the variable “Gender” is coded in the file as numbers (1 and 2). However, you want the words “male” and “female” to show up in the output when you run your test. 7a) Which dialog box is used to create labels such as male and female for specific numbers in the data set? (Give the title at the top of the box.) Answer 7b) If you want to define the level of measurement for the variable “Gender,” which column within Variable View allows you to do this? Answer
Submit Homework 1 by 11:59 p.m. (ET) on Monday of Module/Week 1. Remember to name file appropriately.
PSYC 354 Homework 1 – 6 Assignment Papers
Use the following table to answer Question 1. This table depicts the scores of 40 students on an exam worth 100 points.
1) Use the information in the table to determine the percentages for each interval. Depending on your rounding decisions, these may or may not add up to exactly 100% but should be very close.
Table: Grouped Frequency Table
Score Interval Frequency Percentages for each Interval 90-100 9 ? 80-89 10 ? 70-79 9 ? 60-69 5 ? 50-59 4 ? 40-49 2 ? 30-39 1 ? TOTAL ? ?
2) ________ look like bar graphs but typically display scale data.
3) A frequency distribution that is bell-shaped, symmetrical, and unimodal is ____________.
4) A frequency distribution that has a tail trailing off to the right of the distribution is ____________- skewed.
5) A frequency distribution of ages of residents at an assisted living facility is clustered around 81 with a long tail to the left. This distribution is ____________-skewed.
6) When a constraint prevents a variable from taking on values above a certain point, this is known as a(n) ________ effect.
7) There are two types of graphs that are best to use when graphing two scale variables. Which two graphs are these? _________ and __________
8) When graphing a nominal independent variable and a scale dependent variable, you could use a ________ or a _________.
9) When graphing a single scale variable you should use which type of graph? _________
10) A grouped frequency table has the following intervals: 0–19, 20–39, and 40–59. If converted into a histogram, what would the midpoints be? The process of determining midpoints is best outlined in Example 2.3 of Chapter 2, and illustrated in Ex. 2.4. PSYC 354 Homework 1 – 6 Assignment Papers
30–39: Midpoint Value 40–49: Midpoint Value 50–59: Midpoint Value
11) Do the data in the scatterplot below show a linear relation, non-linear relation, or no relation at all?
12) Do the data in the scatterplot below show a linear relation, non-linear relation, or no relation at all?
Part II: SPSS Analysis
Green and Salkind, Lesson 20
• Open the “Lesson 20 Exercise File 1” document (found in the course’s Assignment Instructions folder) in order to complete these exercises. • Always use the Blackboard files instead of the files on the Green and Salkind website as some files have been modified for the purposes of this course. • Reminder: For Exercise 1, be sure to paste in the SPSS output and write out the answers for A, B, and C beneath it.
Part II: Questions 1-4 • Ann wants to describe the demographic characteristics of a sample of 25 individuals who completed a large-scale survey. • She has demographic data on the participants’: ♣ Gender (two categories) ♣ Educational level (four categories) ♣ Marital status (three categories) ♣ Community population size (eight categories).
Questions 1a -1c
1) Conduct a frequency analysis on the gender and marital status variables. From the output, identify the following: a. Percentage of women b. Mode for marital status c. Frequency of people who have never been married in the sample
Answer- Table- Gender: (paste Table in this cell)
Answer- Table- Marital Status: (paste Table in this cell)
1-a) Percentage of women: Answer
1-b) Mode for marital status (give the name of the group, not the number): Answer
1-c) Frequency of people who have never been married: Answer
2) Create a frequency table to summarize the data on the educational level variable. Answer- Table- Education Level: (paste Table in this cell)
3) Create a bar chart to summarize the data from the community population variable. Answer- Bar chart – Community population: (paste Bar chart in this cell)
4) Write a Participants section describing the participants in Ann’s sample. You may refer to the tables you have created above within the section. PSYC 354 Homework 1 – 6 Assignment Papers Answer- Participants Section:
Part III: SPSS Data Entry and Analysis
The steps will be the same in Part III as the ones you have been practicing in Part I of the assignment; the only difference is that you are now responsible for creating the data file as well. Remember to do the following: • Name and define your variables under the “Variable View,” then return to the “Data View” to enter the data; and • Paste all SPSS output and graphs into your homework file at the appropriate place.
• This question is based on the data in the end-of-chapter Question 2.30 of the Nolan and Heinzen textbook. • Create a variable called “num_years” in a new SPSS file. • Enter the data given in #2.30. o Remember to enter the data into 1 column (variable).
1-a) Create a frequency table in SPSS for these data. Answer- Frequency Table- Number of Years: (paste Table in this cell)
1-b) Create a histogram for these data. Answer- Histogram – Number of Years: (paste Figure in this cell)
1-c) How many schools have an average completion time of 10 years or less? (Each number in the file represents one school.)
An average completion time of 12 years or more? PSYC 354 Homework 1 – 6 Assignment Papers
Answer for 10 years or less =
Answer for 12 years or more =
Fill in the highlighted blanks to answer/complete the statements. 1) Another name for the arithmetic average of a set of numbers is the ________. 2) What is an outlier? ________
3) Which measure of central tendency is most likely to be adversely affected by outliers? ________ 4) We compute standard deviation by taking the ________ of the variance.
For the following terms, write the equivalent mathematical symbol (letter or letters) for the sample statistic. 5-a) Score: Answer 5-b) Mean: Answer
5-c) Standard deviation: Answer 5-d) Number of participants in sample: Answer
These are the scores of eleven patients on the Beck Depression Inventory (BDI ® ). Scores can range from 0 to 63. PSYC 354 Homework 1 – 6 Assignment Papers 12
6-a) What is the mean of the scores? (Compute this using a calculator): Answer 6-b) What is the median of these scores? Answer 6-c ) Compare the mean and median. Does the difference between them suggest that the data are skewed very much? Explain. Answer
Question 7a- 7f
• At this website, (http://projects.newyorker.com/story/subway/) you will find an interactive graph concerning New York City’s geography and income. • Read the introduction and click on different “subway lines” to see how the interactive graph works. • Note that the abbreviations stand for the four different boroughs: ♣ MAN = Manhattan ♣ BRX = Bronx ♣ BRK = Brooklyn ♣ QNS = Queens
• Also note that hovering your mouse over the dots on the graph displays the subway stop and the median income of households in that area. PSYC 354 Homework 1 – 6 Assignment Papers
7-a) In which of the four boroughs is the median household income highest? (This is made evident as you click on the different lines.)
7-b) Click on the “A” line. Does the line graph for Manhattan show high or low variability? What does this level of variability tell us about the household income in this area of Manhattan?
7-c) Click on Line 6. Though both boroughs depicted show some variability, which borough (not a street) shows the most variability in median household income?
7-d) On Line 3, find the following two subway stops: New Lots Ave. (the first of the Brooklyn stops) and Park Place (the first of the highest stops in Manhattan). What is the difference (calculate) between the median household incomes of the two areas?
7-e) Click on the “F” line. Which subway stop in Brooklyn seems to be an outlier?
7-f) Based on this module/week’s reading, why do you think the author of this graph chose the median household income instead of the mean household income to describe central tendency? PSYC 354 Homework 1 – 6 Assignment Papers
Part II: SPSS Analysis
Green and Salkind Course Text, Lesson 21: Exercises 1, 4, 7, and 8 • Questions 1 and 4 o Green and Salkind Text, Lesson 21 o Lesson 21 Exercise File 1 (located under course’s Assignment Instructions folder)
Exercises 1a-1d and Exercise 4
Green and Salkind, Lesson 21, Exercises 1 and 4 ( do not complete numbers 2 or 3) Open “Lesson 21 Exercise File 1” in order to complete these exercises. David collects anxiety scores from 15 college students who visit the university health center during finals week: 1) Compute descriptive statistics on the anxiety scores. From the output, identify the following: a. Skewness b. Mean c. Standard deviation d. Kurtosis
Answer: SPSS Table- Descriptive Statistics for Anxiety Scores (paste Table in this cell)
1-a) Skewness: Answer 1-b) Mean: Answer
1-c) Standard deviation: Answer 1-d) Kurtosis: Answer
4) Create a histogram to show the distribution of the anxiety scores. Edit the graph so that most of the normal curve is visible. Answer: SPSS Figure- Histogram for Anxiety Scores with Normal Curve (paste Figure in this cell)
Part III: SPSS Data Entry and Analysis Data provided below.
The steps will be the same as the ones you have been practicing in Part I of the assignment; the only difference is that you are now responsible for creating the data file, as well. Remember to do the following: a) Name and define your variables under the Variable View, then return to the Data View to enter the data; and b) Paste all SPSS output and graphs into your homework file at the appropriate place. PSYC 354 Homework 1 – 6 Assignment Papers
Part III: Questions 1-4
The following data are based on numbers taken from the Bureau of Labor Statistics surveys from the years 2009–2013, with some modifications. They represent the average weekly pay for wage and salary earners measured at 4 different quarters each year and broken down by gender.
• Enter these data into a new file containing one variable for gender and one variable for salary.
• For the gender variable in column 1, code women as 1 and men as 2 o Remember to define these in Value Labels as covered in presentations since Module 1. o There will be twenty “1”s and twenty “2”s (as many participants as in each group).
• The corresponding earnings will be entered in the salary column (second column).
• If you need an example, look at the set-up of gender in the “Lesson 21 Practice Data File 1” document.
Women 649 654 652 675 660 667 675 668 681 671 685 692 676 689 683 700 692 688 688 694 Men 825 818 813 831 822 851 815 816 833 827 830 828 833 846 837 851 868 831 881 854
1) In SPSS, compute descriptive statistics for each gender for these data. The necessary steps are covered in the last 3 slides of this module’s SPSS tutorial.
Answer- SPSS Table- Descriptive Statistics for Weekly Pay by Gender: (Paste one table; should include weekly pay grouped by men and women)
2) Create a boxplot describing the average overall weekly salary for each gender. Answer- SPSS boxplot: 3) Based on these data, what is the mean weekly income for men? PSYC 354 Homework 1 – 6 Assignment Papers
4) What is the standard deviation of the weekly income for women? Answer
Part IV: Cumulative Questions 1-4
9 10 9 5 17 3 15 20 17 62
15 12 10 4 61 61 22 15 10 11
• The BDI (Beck et al., 1961) is an instrument widely used to assess levels of depression in individuals in a variety of settings.
• The scores range from 0–63 (whole numbers only).
• A researcher administers the BDI to a sample of college students. The results appear in the table below.
• They are entered as two columns to save space (i.e., you will not need two columns in the SPSS file, only one).
1) Using SPSS, run a frequencies analysis on these scores that includes:
• A Frequency Table
• Table of Descriptive Statistics o Include measures of central tendency, dispersion/spread, and distribution.
• Paste the output into your homework file.
Answer- SPSS Table- Frequency Table for BDI Scores:
Answer- SPSS Table- Descriptive Statistics for BDI Scores:
2) Create a graph to describe the data set. Justify why this graph is the best choice for these data. Answer- SPSS graph
Explanation/ Justification 3) Based on your SPSS output, what is the numerical skewness value of this data set? What does this value say about how the scores are distributed? PSYC 354 Homework 1 – 6 Assignment Papers Answer
4) Based on your graph and your answers above, which measure of central tendency is most appropriate for describing this group of scores? Why? Answer Explanation/Rationale
Fill in the highlighted blanks to answer/complete the statements. 1) When a sample has similar characteristics to the population from which it was drawn, the sample is said to be ________.
2) If a finding based on a sample also applies beyond that sample to the entire population, that finding is said to have high external _______.
3) The duplication of the results of a research study in a different context or with a different sample is called ________.
4) Your own estimate of the likelihood that you will win a contest is known as a(n) ________.
5) Expected relative-frequency probability is computed as the number of ________ divided by the number of ________.
6) The ________ group is the group receiving the intervention or treatment of interest.
7) A statement that 2 populations are different from one another is a(n) ________ hypothesis.
8) If you find that the groups you studied differed from each other more than would be expected by chance alone, you ________ the null hypothesis.
9) When you fail to reject the null hypothesis but the null hypothesis is in fact false, you have made a(n) ________ error.
10) When you reject the null hypothesis but the null hypothesis is in fact true, you have made a(n) ________ error.
A school psychologist is interested in whether longer recess breaks affect time on task in the classroom. She divides students into two groups: one with a standard recess length of 10 minutes, and one with a longer recess length of 18 minutes, and assesses their time on task in the classroom over a period of 4 weeks. PSYC 354 Homework 1 – 6 Assignment Papers 11-a) What is the likely null hypothesis for this experiment? Answer 11-b) What is the likely research hypothesis for this experiment? Answer
Complete the following exercises:
12) What is the probability of hitting a target if, in the long run, 15 out of every 125 attempts actually hit the target? Answer (show work) 13) On a TV game show, 6 people have won the grand prize and a total of 159 people have competed. Estimate the probability of winning the grand prize. Answer (show work) 14) Convert the following proportions to percentages: a) 0.356 b) .9 c) .1742 a) Answer b) Answer c) Answer
15) Convert the following percentages to proportions: a) 57.8% b) .5% c) 3.3% a) Answer b) Answer c) Answer
Part II & Part III There is no new SPSS material this module/week. No questions for Part II or III .
Part IV: Cumulative Data provided below for Questions 1 and 2.
99.00 96.00 92.00 89.00 85.00 80.00 78.00 76.00 75.00 74.00 72.00 70.00 70.00 67.00 63.00 59.00 53.00
The final grades for students in a freshman seminar are shown in the left-hand column. Enter the data into a new SPSS data file.
• Create the appropriate SPSS graph to show the distribution of students’ grades.
• Compute descriptive statistics for this data.
• Which measure of central tendency would you use to describe this data?
1-a) Create the appropriate SPSS graph to show the distribution of students’ grades. Answer: SPSS graph
1-b) Compute descriptive statistics for this data. Which measure of central tendency would you use to describe this data? Why? Answer: Appropriate Descriptive Statistics Table
Answer: Measure Of Central Tendency
City Livability Rating
Boston 73 Austin 83 Chicago 73 Pittsburgh 75 San Diego 80 Jacksonville, FL 72 Detroit 67 Miami 71 New York 73 Portland 80 Atlanta 78 Charlotte 77
Questions 2a & 2b
• The overall livability ratings of 12 US cities appear in the columns to the left.
• The data are based on data taken from this livability calculator (http://www.areavibes.com/).
• Enter the data in a new SPSS file. When creating the City variable, be sure that the type is set to “string” or “text” in the Variable View window so that the names will show up on the graph.
2-a) Create the correct type of graph to display this data, and justify your choice of graph. Answer: paste SPSS graph here
Explanation/Justification: 2-b) What level of measurement (nom., ord., scale) is the variable “City”? What level of measurement is the variable “Livability Rating”? Answer Answer
PSYC 354 Homework 1 – 6 Assignment Papers
PSYC 354 HOMEWORK 5 : Z-Ddistribution
PSYC 354 Homework 5 Z-Scores
When submitting this file, be sure the filename includes your full name, course and section. Example: HW5_JohnDoe_354B01
Be sure you have reviewed this module/week’s lesson and presentations along with the practice data analysis before proceeding to the homework exercises. Complete all analyses in SPSS, then copy and paste your output and graphs into your homework document file. Answer any written questions (such as the text-based questions or the APA Participants section) in the appropriate place within the same file. Part I: Concepts
Questions 1–9 These questions are based on the Nolan and Heinzen reading and end-of-chapter questions. PSYC 354 Homework 1 – 6 Assignment Papers
1) What are always the mean and standard deviation of the z-distribution? Answer (mean) 0 Answer (standard deviation) 1
2) Define the central limit theorem. Answer Refers to how the distributuin of sample mean is a normal distribution more than distribution of scores even though the population distribution is not normal.
3) Fill in the blanks: A z-score can be thought of as the number of ___ that a score is from the mean. Part I: Questions 4-8
Remember to show work to receive partial credit where applicable. For help working on these problems, refer to the presentation from this module/week on the normal curve and computing z-scores. 4) Calculating z scores from raw scores: If a population has a mean of =198 and a standard deviation of = 20, calculate z scores for each of the following raw scores (X) from this population. Show work on the right hand side, put answers on the left in the space provided. PSYC 354 Homework 1 – 6 Assignment Papers 4
a) X = 210; Z = 0.6 Work:(210-198)/20=0.6 4b) X = 231; Z = 1.65 Work: (231-198)/20=1.65 4c) X = 179; Z = -0.95 Work: (179-198)/20= -0.95 4d) X = 163; Z = -1.75 Work: (163-198)/20= -1.75 5) Calculating raw scores from z scores: If a population has a mean of =198 and a standard deviation of = 20, calculate raw scores (X) for each of the following z scores from this population. Show work on the right hand side, put answers on the left in the space provided. 5a) Z = .56; X = 209.2 Work: .56(20) + 198 = 209.2 5b) Z = -2.44; X = 149.2 Work: -2.44(20) + 198 = 149.2 5c) Z = -1.0; X = 178 Work: -1.0(20) + 198 = 178 5d) Z = 1.83; X = 234.6 Work: 1.83(20) + 198 = 234.6
6) In a normal curve, what percentage of scores falls: 6a) Above the mean? Answer Work: 6b) Between -1 and +1 standard deviations (SD) from the mean? Answer Work: 6c) Beyond 2 SD’s away from the mean (in the tails on both sides)? Answer Work: 6d) Between the mean and 2 SD’s above the mean? Answer Work:
7) Compute the standard error (m) for each of the following sample sizes, assuming a population mean of 125 and a standard deviation of 20. PSYC 354 Homework 1 – 6 Assignment Papers 7a) 40 Answer Work: 7b) 140 Answer Work: 7c) 1400 Answer Work:
8) Compute a z-statistic for each of the following sample means, assuming the population has a mean of 100 and a standard deviation of 30 (Remember to compute M before computing the z statistic!) 8a) A sample of 32 scores has a mean of 113 Answer Work: 8b) A sample of 80 scores has a mean of 95 Answer Work: 8c) A sample of 50 scores has a mean of 100. Answer Work: Part II: SPSS Analysis
Module 5 Lesson 21 Exercise File 1 Open the “Lesson 21 Exercise File 1” document (found in the course’s Assignment Instructions folder) in order to complete these exercises. Part II:
Use file: Module 5 Lesson 21 Exercise File 1 Using the data set (answers will be pasted into the blanks below this summary):
• a) Create a histogram of the raw scores
• b) Transform the raw scores to z-scores o Label the new variable “z_anxiety”
• Paste Descriptive Statistics Table of the raw anxiety scores o Note that descriptive statistics should describe the original raw scores and not the new z scores
• c) Identify the z-score that is closest to 0 and farthest from 0.
• d) Evaluate whether the scores are normally distributed. o Support your answer. 1a) Create a histogram of the anxiety raw scores and paste it below. Answer: Histogram 1b) Using the descriptives method covered in the presentation and chapter, transform the anxiety raw scores to z-scores, creating a new variable called “z_anxiety.” Paste the output of descriptive statistics in the cell below. These descriptive statistics should describe the original raw scores and not the new z-scores. PSYC 354 Homework 1 – 6 Assignment Papers
Answer: Descriptive Statistics Table Descriptive Statistics N Range Minimum Maximum Mean Std. Deviation Variance Skewness Kurtosis Statistic Statistic Statistic Statistic Statistic Std. Error Statistic Statistic Statistic Std. Error Statistic Std. Error Anxiety Scores 15 73 5 78 32.27 6.062 23.478 551.210 .416 .580 -1.124 1.121 Valid N (listwise) 15
What is the z-score that is closest to 0 (on either side of the mean) in the data set? What is the z-score that is the farthest from 0 (on either side of the mean) in the data set? Answer Answer 1d) Based on the histogram from (1a) and your other answers above, would you describe the anxiety data as being normally distributed? Why or why not? Support your answer with information from the chapter and presentations regarding normal and standard normal z-distributions. PSYC 354 Homework 1 – 6 Assignment Papers Answer Justification Part III: SPSS Data Entry and Analysis
Data provided below. IQ Scores 79 120 104 145 108 100 115 107 60 122 105 87 98 124 82 93 89 123 117 104 112 96 88 98 105 91 113 123 124 90
The data in the columns to the left represent IQ scores of a sample of 30 high school students. In the general population, IQ scores have a mean of 100 and a standard deviation of 15. Enter this data into SPSS. Be sure to save this file, since you will be using it next week as well.
• Generate descriptive statistics for this variable.
• Generate a histogram for this variable.
• In your data set, standardize the IQ scores by transforming them into z-scores o Label the new variable “ZIQ” • Which z-scores corresponds to a raw IQ score of 115, 79 and 107?
• Does the distribution reflect the distribution in the general population? o Support your answer. 1-a) Generate descriptive statistics for this variable. Answer: Descriptive Statistics Table 1-b) Generate a histogram for this variable. Answer: Histogram 1-c) In your data set, standardize the IQ scores by transforming them into z-scores under a new variable “ZIQ.” Using your data set as a reference, what z-score corresponds to a raw IQ score of 115? To a raw IQ score of 79? To a raw IQ score of 107? 115 Answer 79 Answer 107 Answer 1-d) Based on what you have been told about IQ scores in the beginning of the problem, does this sample’s distribution seem to reflect the distribution of IQ scores in the general population? Why or why not? PSYC 354 Homework 1 – 6 Assignment Papers Answer Justification Part IV: Cumulative
Data provided below for respective questions.
Part IV: Question 1a-1d (Non-SPSS)
A cognitive psychologist wants to find out whether playing Minecraft® affects fourth graders’ scores on a visuospatial task. He assigns 30 fourth graders to 1 of 2 groups. Group 1 plays Minecraft® for 20 minutes, then completes the visuospatial task. Group 2 completes the visuospatial task without playing Minecraft®. 1-a) What is the independent variable in this experiment? Answer Minecraft 1-b) What is the dependent variable? Answer The visuospatial task 1-c) What is the likely null hypothesis for this experiment? Answer The null hypothesis is that there is no difference in affect from playing minecraft and performing visuospacial task. 1-d) What is the likely research hypothesis for this experiment? Answer fourth grades are showing affected scores on visuospacial task after playing minecraft. ASPD Diagnosis No ASPD Diagnosis 30 12 20 21 27 9 17 27 34 32 9 8 18 12 6 5 8 14 10 4
Questions 2a & 2b (SPSS)
A forensic psychologist wants to examine the level of narcissistic personality traits in those who are diagnosed with antisocial personality disorder (ASPD) and those who do not qualify for ASPD within a local prison population. She administers a measure of narcissistic personality traits where higher scores indicate higher levels of narcissism and scores range from 0–35. PSYC 354 Homework 1 – 6 Assignment Papers
• Create a new SPSS data file for these scores.
• Your file must have 2 variables: Diagnosis and Score.
• Your diagnosis variable must be set up as a 1-column grouping variable with 2 groups (diagnosis, no diagnosis) coded numerically. This will be much like the gender variable you created in a previous module/week. o For example, if you code ASPD Diagnosis as 1 and No ASPD Diagnosis as 2, then the SPSS file will appear somewhat like the following: Column 1 Column 2 “Diagnosis” “Score” 1 23 1 11 1 19
• All ASPD Diagnosis scores from the table above will appear in a similar fashion.
• Then, continuing in the same columns, enter No ASPD Diagnosis information as: Column 1 Column 2 2 10 2 8 2 19 [Continue in this fashion to the end of the file]
• a) Compute descriptive statistics by diagnosis (that is, for each of the two groups in one table) using similar steps to those covered in Green and Salkind’s Lesson 21 and in the Module/Week 3 presentation (HS GPA scores by Gender).
• b) Construct a boxplot to show the difference between the mean scores of the 2 groups 2-a) Compute descriptive statistics by diagnosis (that is, for each of the two groups in one table) (2 pts) Answer: SPSS Table- Descriptive Statistics for Score (level of narcissistic personality) grouped by Diagnosis (ASPD/No ASPD): [Paste one table] 2-b) Construct a boxplot to show the difference between the mean scores of the 2 groups. (3 pts) Answer: Boxplot Submit Homework 5 by 11:59 p.m. (ET) on Monday of Module/Week 5. Remember to name file appropriately.
Part I: Questions 1-7
• Answer the following questions.
• If applicable, remember to show work in your homework document for partial credit.
1) What are the 6 steps of hypothesis testing? (State the 6 steps) A) B) C) D) E) F) 2) Using the z table in Appendix B, calculate the following percentages for a z score of -0.45 2-a) % above this z score: Answer Work:
2-b) % below this z score: Answer Work:
2-c) At least as extreme as this z score (on either side): Answer Work: 3) Rewrite each of the following percentages as probabilities, or p levels: 3-a) 5% = Answer
3-b) 95% = Answer
3-c) 43% = Answer 4) If the critical values, or cutoffs, for a two-tailed z test are -2.05 and +2.05, determine whether you would reject or fail to reject the null hypothesis in each of the following cases: 4a) z = 2.23 Answer 4b) z = -0.97 Answer
5) Imagine a class of twenty-five 12-year-old girls with an average height of 62 inches. We know that the population mean and standard deviation for this age group of girls is m=59 inches, s = 1.5 inches. (Note that this is a z statistic problem.)
5a) Calculate the z statistic for this sample (not the z score). Answer
5b) How does this sample mean compare to the distribution of sample means? In other words, how does the height of the girls in the sample compare to the height of girls in th general population? Answer
6) For the following scenarios, identify whether the researcher has expressed a directional or a nondirectional hypothesis:
6a) Social media has changed the levels of closeness in long-distance relationships. Answer
6b) A professor wonders whether students who eat a healthy breakfast score better on exams in morning courses than those who do not eat a healthy breakfast. PSYC 354 Homework 1 – 6 Assignment Papers Answer 7) For the following scenario, state the null and research hypotheses in both words and symbolic notation. Symbolic notation must include the symbols “” and “” and a comparison operator (=, , <, >, , ), as described in Nolan and Heinzen (2014). Remember to consider whether the hypothesis is nondirectional or directional. Scenario: A professor wonders whether students who eat a healthy breakfast score better on exams in morning courses than those who do not eat a healthy breakfast. Null Hypothesis (H0): Symbolic Notation Answer
Null Hypothesis: Written Statement Answer
Research Hypothesis (H1): Symbolic Notation Answer Research Hypothesis: Written Statement Answer
Part I: Questions 8a-8g Fill in the highlighted blanks with the best word or words. 8-a) Values of a test statistic beyond which you reject the null hypothesis are called ________. 8-b) The ________ is the area in the tails in which the null can be rejected.
8-c) The probability used to determine the critical values, or cutoffs, in hypothesis testing is known as a ________ level, also known as alpha.
8-d) If your data differ from what you would expect if chance were the only thing operating, you would call your finding ________. 8-e) A hypothesis test in which the research hypothesis is directional is a(n) ________ test.
8-f) A hypothesis test in which the research hypothesis specifies that there will be a difference but does not specify the direction of that difference is a(n) ________ test.
8-g) If your z-statistic exceeds the critical cutoff, you can ________ the null hypothesis.
Part I: Questions 10a-10c
The police department of a major city has found that the average height of their 1,200 officers is 71 inches (in.) with = 2.6 inches. Use the normal distribution and the formulas and steps in this week’s presentations to answer the following questions:
Note: Showing work is required for this section. Remember that it helps to transfer the raw mean and SD from the description above to the standardized curve shown here (though you don’t need to show this). This helps compare raw and z scores and check your work. 10a) What is the z score for an officer who is 72 inches tall? Based on the z score and the z table, what is the officer’s percentile? (Hint: See slide 7 of this week’s related presentation). PSYC 354 Homework 1 – 6 Assignment Papers Answer (z score): Work (required):
Answer (percentile): Work/reasoning using z table (required): 10b) What is the height (in inches) that marks the 80th percentile for this group of officers? (Hint: See slides 14-16 of this week’s related presentation)
10c) What percent of officers are between 68 and 72 inches tall? (Hint: See slide 12 of this week’s related presentation) Answer Work (required):
Part I: Questions 11a-11c
The verbal part of the Graduate Record Exam (GRE) has a of 500 and = 100. Use the normal distribution and the formulas and steps in this week’s presentations to answer the following questions:
Note: Showing work is required for this section. Remember that it helps to transfer the raw mean and SD from the description above to the standardized curve shown here (though you don’t need to show this). This helps compare raw and z scores and check your work. 11a) What is the z score for a GRE score of 583? What is the percentile rank of this z score? (Hint: See slide 7 of this week’s related presentation) Answer (z score): Work (required):
Answer (percentile): Work (required): 11b) What GRE score corresponds to a percentile rank of 25%? (Hint: See slide 17 of this week’s related presentation) Answer Work (required): 11c) If you wanted to select only students at or above the 82nd percentile, what GRE score would you use as a cutoff score (i.e. what GRE score corresponds to this percentile)? (Hint: See slides 14-16 of this week’s related presentation) Answer Work (required):
Part II: SPSS Analysis
For this section, you will be using last module/week’s data set containing IQ scores. Open the file; it should also contain the standardized IQ variable you created last module/week.
Part II: Question 1a & 1b
Use last week’s HW file that you created using IQ scores, and the SPSS reading and presentation from this week. • Using the z-scored IQ variable, create percentile ranks assuming the scores are normally distributed. o Call the new percentile variable “IQ rank.”
1a) List the first 5 IQ ranks from your file (rows 1–5). Answer: Row 1: Row 2: Row 3: Row 4: Row 5:
1b) Which raw IQ score seems to best divide the top 50% from the bottom 50% of scores? (This score can be found by looking carefully over the values in the IQ rank column) Answer
Part III: SPSS Data Entry and Analysis
There is no Part III material this module/week.
Part IV: Cumulative Data provided below for respective questions.
Part IV: (Non-SPSS) Questions 1-4
For a distribution with M = 40 and s = 5:
1) What is the z-score corresponding to a raw score of 32? Answer Work: 2) What is the z-score corresponding to a raw score of 50? Answer Work: 3) If a person has a z-score of 1.8, what is his/her raw score? Answer Work: 4) If a person has a z-score of -.63, what is his/her raw score? Answer Work:
Part IV: (Non-SPSS) Question 5-8 For the following types of data, state the graph that would be the best choice to display the data. Two items have more than one correct answer—for these, either answer is acceptable. PSYC 354 Homework 1 – 6 Assignment Papers 5) A nominal independent variable (IV) and a scale dependent variable (DV) Answer 6) One scale variable with frequencies (when you want to see the general shape of the distribution). Answer 7) One scale IV and one scale DV Answer 8) One nominal variable broken down into percentages Answer
PSYC 354 HOMEWORK 7 Confidence Intervals, Effect Size, and Statistical Power
When submitting this file, be sure the filename includes your full name, course and section. Example: HW7_JohnDoe_354B01 Be sure you have reviewed this module/week’s lesson and presentations along with the practice data analysis before proceeding to the homework exercises. Complete all analyses in SPSS, then copy and paste your output and graphs into your homework document file. Answer any written questions (such as the text-based questions or the APA Participants section) in the appropriate place within the same file. Part I: Concepts
Questions 1–8 These questions are based on the Nolan and Heinzen reading and end-of-chapter questions.
Part I: Questions 1a-1e Fill in the highlighted blanks with the best word or words. 1-a) The confidence interval is centered around the _mean_______ of the sample. 1-b) Cohen’s d measures the difference between means in terms of ___standard deviation not standard error_____. According to Cohen’s conventions, a d value of _appropriate measure of effect size 1-c) for a z statistic_______ indicates a small effect. A study that calculates the mean effect size from the individual effect sizes of many 1-d) studies is called a(n) __meta analysis______. Statistical power refers to the probability of successfully rejecting the _null 1-e) hypothesis_______.
Part I: Questions 2-5 End-of-chapter problems: Complete the following problems. Page 1 of 5 PSYC 354 If applicable, remember to show work in your homework document to receive partial credit. 2) List five factors that affect statistical power. For each, indicate how a researcher can leverage/manipulate that factor to increase power in a study. A) Sample Size (increase sample size) B) )Effect Size (increase predicted difference between means/decrease population standard deviation) C) Alpha Level (use less extreme alpha level), D) Test Direction (use a one-tailed test E) Type of Hypothesis Test Used (use more sensitive hypothesis test) 3) Exercise 8.22 from N&H text: In 2006, approximately 47% of Americans, when surveyed by a Gallup poll, felt that having a gun in the home made them safer than having no gun. The margin of error reported was 3%. Construct an interval estimate using these figures. Answer44% – 50% is our interval estimate 4) For each of the following confidence levels, look up the critical z values for a two-tailed test. 4a) 80% (Hint: 10% in each tail): Answer