Assignment 1: Final Exam

The purpose of this exam is to give you the opportunity to formulate research questions, run the analyses, and interpret the results of the statistics covered in this class. The final exam is due by midnight on the due date, by the due date assigned, as a single Microsoft Word document placed in the Submissions Area. The document must be in APA format.

Please read through the entire exam first.

The exam consists of three sections

I. The research scenario—to provide the context for the data. Please note that the data are “content-neutral,” i.e., they do not refer to a specific discipline or field.

II. The codebook—this identifies the variables (names, labels, and measurement scale) in the database.

III. The exam instructions—for completing the exam. Be sure to read each question carefully and answer each question completely.

I. Research Scenario:

An organization wants to know if participants with varying levels of expertise (professionals, paraprofessionals, and nonprofessionals) improve their knowledge after completing a training program.

The organization collected demographic information: gender, age, type of training (professional, paraprofessional, or nonprofessional), location of the worksite (on-site or off-site) and years of experience.

A pre-training test of knowledge, a training program, and post-training test of knowledge was developed. Participants were tested, then participated in the three-week training program, and then were tested again.

The dataset also includes (1) a measure of participant confidence in knowledge and (2) a certification exam score.

The data are discipline-neutral. Therefore, part of your final project is to create a context for the research that is associated with your discipline or area of interest (e.g., training to assess mental health status; training to work with special education children; training to become a technician or consultant).

II. Codebook

Variable InformationVariableLabelMeasurement ScaleCatagory NameIDN/AN/AN/AGenderGenderNominal

1 = Male
2 = Female

ageAge in YearsRatio 

qualification

Professional Qualification

Nominal1 = Professional
2 = Paraprofessional
3 = NonprofessionalworksiteLocation of WorkNominal1 = On-Site
2 = Off-Siteknowledge1Level of knowledge before TrainingIntervalN/Aknowledge2Level of knowledge after TrainingIntervalN/AyearsYears of ExperienceRatioN/AconfidenceConfidence in knowledgeIntervalN/AexamCertification in knowledgeIntervalN/A

III. Exam Instructions

Overview
Your task is to review the dataset, formulate a context, and then use your knowledge of statistics to answer the research questions and test hypotheses that will help the organization evaluate the effectiveness of the program.

Part I. Create your context.

Using the research scenario and variables identified in the codebook, create a “story” that describes the purpose and focus of the study. In a few paragraphs describe the intent of your investigation in the form of a problem background and purpose statement.

Part II. Describe your sample.

Generate frequency tables and bar charts for the nominal variables. Generate and interpret descriptive statistics of central tendency, variability, skewness, and kurtosis for the continuous (scale) variables. Generate frequency tables and histograms with the normal curve superimposed for each scale variable. Label your tables and graphs according to APA format. Conclude with a paragraph summarizing the demographic characteristics of this sample.

1. Gender (nominal)
2. Age (scale)
3. Qualification (nominal)
4. Worksite (nominal)
5. Knowledge1 (scale)
6. Knowledge2 (scale)
7. Years (scale)
8. Confidence (scale)
9. Exam (scale)

Part III. Describe relationships among the variables.

Select the variables that are measured on interval or ratio scales. Create a correlation matrix.  Label the table according to APA format. Identify and discuss the strongest and weakest correlations.

Part IV. Answer any FOUR of the nine following research questions. Clearly identify which question(s) you have selected to answer by writing the number associated with the question (1-9) before each answer. Make sure to select four questions that must be answered by 4 DIFFERENT tests. For example. One t-test, one ANOVA, one regression and one chi-square; NOT a single sample t-test, independent sample t-test and paired sample t-test as these all fall under t-test.

Based on the research scenario and the data, restate the research question, identify the Independent and Dependent Variable(s), formulate the hypothesis, conduct an analysis, and interpret the results for each of the following. Please use the 7 step hypothesis testing model for each analysis, including an APA-style conclusion statement summarizing the findings, interpreting the results and answering the research question.

1. Is there a significant difference in knowledge between on-site and off-site workers beforethey take the training?
2. Is there a significant increase in knowledge as a result of the training?
3. Do participants of different classifications (professional, paraprofessional, and nonprofessional) perform differently on the certification exam? Which group performs best?
4. What are the effects of gender and worksite location (on- or off-site) on level of confidence? In other words:
   1. Is there a gender difference in confidence?
   2. Does type of worksite experience affect confidence?
   3. Is there an interaction between gender and worksite in their effect on confidence?
5. After controlling for prior knowledge, is there a difference between professionals, paraprofessionals, and non-professionals in knowledge after the training?
6. Does age predict performance on the certification exam?
7. In addition to age, does confidence improve the ability to predict performance on the certification exam?
8. Does the distribution of the classifications of participants (professional, paraprofessional, and nonprofessional) differ than what one would expect by chance?
9. Does the distribution of the classifications (professional, paraprofessional, and nonprofessional) differ from the State data reported as 15%, 25% and 60%?

Part V. Summarize your findings.

Synthesize the results of your four analyses. Include a brief summary of the sample characteristics and the major findings. Interpret the findings so that the organization’s leaders will have an understanding of the similarities and differences in knowledge, and how effective the training program is in improving knowledge.

All written assignments and responses should follow APA rules for attributing sources.

Assignment 1 Grading CriteriaMaximum Points

Part I.  Create your context.
Using the research scenario and variables identified in the codebook, create a “story” that describes the purpose and focus of the study. In a few short paragraphs describe the intent of your investigation in the form of a problem background and purpose statement.

10 = problem background described
10 = purpose described
5 = relevance to field of study
5 = APA format and writing style

30

Part II. Describe your sample.
Generate frequency tables and bar charts for the nominal variables. Generate and interpret descriptive statistics of central tendency, variability, skewness, and kurtosis for the continuous (scale) variables. Generate frequency tables and histograms with the normal curve superimposed for all scale variables. Label your tables and graphs according to APA format. Conclude with a paragraph summarizing the demographic characteristics of this sample.

Displays correct choice of graph or chart and describes sample using correct descriptive statistics
5 = Gender
10 = Age
5 = qualification
5 = worksite
10 = knowledge1
10 = knowledge2
10 = years
10 = confidence
10 = exam
5 = APA format and writing style

80

Part III. Describe relationships among the variables.
Select the variables that are measured on interval or ratio scales. Create a correlation matrix. Label the table according to APA format. Identify and discuss the strongest and weakest correlations.

10 = identify and discuss strong positive and negative correlations.
10 = identify and discuss weak positive and negative correlations.
5 = APA format and writing style

25

Part IV. Answer FOUR of the nine following research questions.
Based on the research scenario and the data, you restate the research question, formulate the hypothesis, conduct an analysis, and interpret the results for each of the following. Please use the 7-step hypothesis testing model for each analysis, including a summary statement interpreting the results and answering the research question. You should select items so that you present 4 different types of analyses.

24 = Correct hypothesis
24 = Correct choice of statistical technique
24 = Correct tables
32 = Correct summary and interpretation
24 = APA format and writing style

Question Breakdown: (32 pts each)

6 = Correct hypothesis
6 = Correct choice of statistical technique
6 = Correct tables
8 = Correct summary and interpretation
6 = APA format and writing style

128

Part V. Summarize your results.
Summarize the findings and relate them to the stated purpose of the research. This includes a brief summary of the sample characteristics, including (based on your results) interesting differences between groups. Then, discuss what the results say about the effectiveness of the program that would be relevant to the organization’s intent.

5 = Summarize findings
14 = Describe and interpret sample characteristics and differences in knowledge
14 = Interpret results in terms of program effectiveness
4 = APA format and writing style

37Total:300 

 

Visit https://data.cdc.gov and select one of the data sets that you find interesting. The dataset you choose must contain at least 3 columns of quantitative data with at least 30 data values in each column. If it doesn’t, you won’t be able to complete most parts of this assignment.

You will use this data set to develop a position paper to your county health department describing the importance of the data and how this data will impact clinical practice.

• Part 1–  download and import the data set into StatCrunch or Excel. Create an APA formatted paper with references (the entire paper needs to be in APA format) that contains the following:

1. Identify the dependent and independent variables.
2. Identify a probability distribution based on your data set and explain the results.
3. Calculate the correlation coefficient between two variables and run a regression. You should identify whether there is a statistically significant relationship between the variables. Provide the regression line calculated and the line shown on the scatterplot. Make sure to include the computer output in your document. Interpret the slope coefficient.
4. Create a minimum of 3 graphs (learned in this course) that utilize your variables and label each graph. Explain what they show.
5. Inferential Statistics
   1. Using one of your columns of quantitative data, construct a 95% confidence interval (using StatCrunch). Make sure to include the computer output in your document. Explain the results.
   2. Using another one of your columns of quantitative data, construct a 95% confidence interval (using StatCrunch). Make sure to include the computer output in your document. Explain the results.
   3. Using one of your columns of quantitative data, identify and explain a null & alternative hypotheses for that data. Using StatCrunch, complete the hypothesis test to make a decision about your hypotheses statements. Make sure to include the computer output in your document. This hypothesis test should test a single mean or single proportion. Explain the results.
   4. Using two of your columns of quantitative data, identify and explain a null & alternative hypotheses for that data. Using StatCrunch, complete the hypothesis test to make a decision about your hypotheses statements. Make sure to include the computer output in your document. This hypothesis test should compare two means or two proportions. Explain the results.

• Part 2– in a 1-2 page APA formatted position paper, describe the data set you selected and provide a link. Utilizing the data, graphs, and tests that you have fun in Part I, clearly explain how the results support your stance on the importance of this information and how the data will impact clinical practice. Be sure to include a link to the data you selected.
• Part 3  provide a step by step overview showing how you create the three graphs 

t Tests

See the Resources area for links to resources that you will use for this assignment:

• You will complete this assignment using the DAA Template.
• Read the SPSS Data Analysis Report Guidelines for a more complete understanding of the DAA Template and how to format and organize your assignment.
• Refer to the IBM SPSS Step-By-Step Guide: t Tests for additional information on using SPSS for this assignment.
• If necessary, review the Copy/Export Output Instructions to refresh your memory on how to perform these tasks. As with your previous assignments, your submission should be in narrative format with supporting statistical output (table and graphs) integrated into the narrative in the appropriate places (not all at the end of the document).

You will analyze the following variables in the grades.sav data set:

• gender
• gpa

Step 1: Write Section 1 of the DAA.

• Provide the context of the grades.sav data set.
• Include a definition of the specified variables (predictor, outcome) and corresponding scales of measurement.
• Specify the sample size of the data set.

Step 2: Write Section 2 of the DAA.

• Analyze the assumptions of the t test.
• Paste the SPSS histogram output for gpa and discuss your visual interpretations.
• Paste SPSS descriptives output showing skewness and kurtosis values for gpa and interpret them.
• Paste SPSS output for the Shapiro-Wilk test of gpa and interpret it.
• Report the results of the Levene test and interpret it.
• Summarize whether or not the assumptions of the t test are met.

Step 3: Write Section 3 of the DAA.

• Specify a research question related to gender and gpa.
• Articulate the null hypothesis and alternative hypothesis.
• Specify the alpha level.

Step 4: Write Section 4 of the DAA.

• Paste the SPSS output of the t test.
• Report the results of the SPSS output using proper APA guidelines (refer to the Unit 8 Introduction and the "Results" example from the Warner text in Chapter 5). Include the following:      
  • t.
  • Degrees of freedom.
  • p value.
  • Effect size.
  • Interpretation of effect size.
  • Means and standard deviations for each group.
  • Mean difference.
  • 95% confidence interval of the difference of sample means.
• Interpret the results against the null hypothesis.

Step 5: Write Section 5 of the DAA.

• Discuss the implications of this t test as it relates to the research question.
• Conclude with an analysis of the strengths and limitations of the t test.

 

Competency

Determine and interpret the linear correlation coefficient, and use linear regression to find a best fit line for a scatter plot of the data and make predictions.

Scenario

According to the U.S. Geological Survey (USGS), the probability of a magnitude 6.7 or greater earthquake in the Greater Bay Area is 63%, about 2 out of 3, in the next 30 years. In April 2008, scientists and engineers released a new earthquake forecast for the State of California called the Uniform California Earthquake Rupture Forecast (UCERF).

As a junior analyst at the USGS, you are tasked to determine whether there is sufficient evidence to support the claim of a linear correlation between the magnitudes and depths from the earthquakes. Your deliverables will be a PowerPoint presentation you will create summarizing your findings and an excel document to show your work.

Concepts Being Studied

• Correlation and regression
• Creating scatterplots
• Constructing and interpreting a Hypothesis Test for Correlation using r as the test statistic

You are given a spreadsheet that contains the following information:

• Magnitude measured on the Richter scale
• Depth in km

Using the spreadsheet, you will answer the problems below in a PowerPoint presentation.

What to Submit

The PowerPoint presentation should answer and explain the following questions based on the spreadsheet provided above.

• Slide 1: Title slide
• Slide 2: Introduce your scenario and data set including the variables provided.
• Slide 3: Construct a scatterplot of the two variables provided in the spreadsheet. Include a description of what you see in the scatterplot.
• Slide 4: Find the value of the linear correlation coefficient r and the critical value of r using α = 0.05. Include an explanation on how you found those values.
• Slide 5: Determine whether there is sufficient evidence to support the claim of a linear correlation between the magnitudes and the depths from the earthquakes. Explain.
• Slide 6: Find the regression equation. Let the predictor (x) variable be the magnitude. Identify the slope and the y-intercept within your regression equation.
• Slide 7: Is the equation a good model? Explain. What would be the best predicted depth of an earthquake with a magnitude of 2.0? Include the correct units.
• Slide 8: Conclude by recapping your ideas by summarizing the information presented in context of the scenario.

Along with your PowerPoint presentation, you should include your Excel document which shows all calculations.

Unit 7 Discussion Discussion Topic

Updated

ConversionsIn Unit 7, you are learning about the metric system and making conversions within the metric system. Many believe that conversions in the metric system are easier to make, while others believe conversions within the U.S. system are easier.During this unit, you will explore two different measurement systems: The metric system and the U.S. system of measurement. You will be exposed to both measurement systems either by converting a measurement in that specific system or commenting on a student’s conversion in a different system.Post 1Begin your response by stating the measurement system you believe is easier to make conversions in, the U.S. system or the metric system. Justify your reasoning with supporting details as to why you believe this system is easier.If you believe that metric conversions are easier, write and post a metric conversion. Choose a four-digit number with no numbers repeated and convert from one unit to another. For example, convert 3450 decigrams to kilograms. You can convert between any two units shown in Table 8.1 on page 437 of the text. Or, if you are feeling a little more adventurous, you can choose between any two units on the table shown on page 438 of the text. Write a complete explanation, showing all steps used in the conversion. Explain each step as if you were the expert explaining it to a novice.— or —If you think that U.S. conversions are easier, write and post a U.S. conversion problem using one of the following conversions.If you need to find the conversion factors, they are readily available on in the Internet. Do not forget to post a link to the site where you found your conversions. NOTE: You must show the conversion step by step including the intermediate conversion. For example, when converting from inches to yards, you must first convert to feet and then convert to yards. Explain how to do the conversion showing all work. Be sure to explain each step of your conversion in words as well as showing the math work.Discuss a real-life situation where you may use this conversion.Review an example of a response for this Discussion.