Chat with us, powered by LiveChat How to compute and interpret a reliability coefficient for the subscales in the dataset. - Writingforyou

How to compute and interpret a reliability coefficient for the subscales in the dataset.

PSYC 545

SPSS: Reliability Assignment Instructions

Overview

Beginning with the data set from SPSS: Descriptive Statistics Assignment, you will learn how to compute and interpret a reliability coefficient for the subscales in the dataset.

Recall that our data set contains data for the Grit Scale (Duckworth, Peterson, Matthews, & Kelly, 2007). At this point, Grit Scale items 1, 4, 6, 9, 10, and 12 should be reverse-scored as separate variables. We will need these for this assignment.

The data set also contains the Big-Five Inventory (BFI; Goldberg, 1992), a measure of five personality constructs. Items are labeled based on the subscale to which it belongs.

Subscale

Item ID

Item Text

Extraversion

E1

I am the life of the party.

E2*

I don't talk a lot.

E3

I feel comfortable around people.

E4*

I keep in the background.

E5

I start conversations.

E6*

I have little to say.

E7

I talk to a lot of different people at parties.

E8*

I don't like to draw attention to myself.

E9

I don't mind being the center of attention.

E10*

I am quiet around strangers.

Neuroticism

N1

I get stressed out easily.

N2*

I am relaxed most of the time.

N3

I worry about things.

N4*

I seldom feel blue.

N5

I am easily disturbed.

N6

I get upset easily.

N7

I change my mood a lot.

N8

I have frequent mood swings.

N9

I get irritated easily.

N10

I often feel blue.

Agreeableness

A1*

I feel little concern for others.

A2

I am interested in people.

A3*

I insult people.

A4

I sympathize with others' feelings.

A5*

I am not interested in other people's problems.

A6

I have a soft heart.

A7*

I am not really interested in others.

A8

I take time out for others.

A9

I feel others' emotions.

A10

I make people feel at ease.

Conscientiousness

C1

I am always prepared.

C2*

I leave my belongings around.

C3

I pay attention to details.

C4*

I make a mess of things.

C5

I get chores done right away.

C6*

I often forget to put things back in their proper place.

C7

I like order.

C8*

I shirk my duties.

C9

I follow a schedule.

C10

I am exacting in my work.

Openness

O1

I have a rich vocabulary.

O2*

I have difficulty understanding abstract ideas.

O3

I have a vivid imagination.

O4*

I am not interested in abstract ideas.

O5

I have excellent ideas.

O6*

I do not have a good imagination.

O7

I am quick to understand things.

O8

I use difficult words.

O9

I spend time reflecting on things.

O10

I am full of ideas.

*Reverse-scored.

Respondents used the following scale for the BFI:

1

2

3

4

5

Disagree

Neutral

Agree

As noted in the first table, there are also several items in the BFI that are worded to be the opposite of the construct. Just like the Grit Scale in SPSS: Descriptive Statistics Assignment, these items, denoted with an asterisk (*), will need to be reverse-scored prior to any analyses. Use the naming convention for reverse-scored items: “E2” becomes “E2r” as a separate variable. After reverse-scoring, your items are ready to assess the internal consistency of the scale.

Instructions

For this assignment, you will:

1. Reverse-score the appropriate BFI items. As described above, reverse-score the BFI items just like you did with the Grit Scale. Again, this is so that higher scores mean higher levels of the construct.

1. Calculate Cronbach’s coefficient alpha (α) for the Grit Scale and each BFI subscale. Be sure to click all boxes as shown in the SPSS Tutorial. Create an APA-formatted table in Word that displays the sample size ( n), number of items ( k), and Cronbach’s alpha for each of the six subscales (Grit, Extraversion, Neuroticism, Agreeableness, Conscientiousness, Openness).

1. Examine the Cronbach’s alpha output for each subscale. Look at the “Corrected Item-Total Correlations” columns. Are any negative? Did you analyze the reverse-scored items? If you used the reverse-scored items, move on to the next step.

1. Write a verbal summary discussing the results of your internal consistency analysis. This summary section will include 2 elements:

1. Summarize the results of the reliability analysis. What sample size are these results based on? How many items are in each scale and what was the response scale given?

1. Interpret the values that you found from the various analyses. Are the Cronbach’s alphas of acceptable magnitude? Are there any items that correlate negatively with the total scores? Would you suggest removing any items based on these findings?

1. Format your table headings and figure captions according to current APA guidelines.

Each of these steps are to be completed in SPSS using the SPSS Tutorials as a guide. Please submit a Word document with your table and verbal summary.

Note: Keep your data set handy. The next assignment will build upon the progress you have made on this data set.

Note: Your assignment will be checked for originality via the Turnitin plagiarism tool.

References

Duckworth, A.L., Peterson, C., Matthews, M.D., & Kelly, D.R. (2007). Grit: Perseverance and passion for long-term goals. Journal of Personality and Social Psychology, 9, 1087-1101.

Goldberg, L. R. (1992). The development of markers for the Big-Five factor structure. Psychological Assessment, 4, 26-42.

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RELIABILITY 1

RELIABILITY 4

SPSS: Reliability Assignment

Liberty U. Student

Department of Psychology, Liberty University

Author Note

Correspondance concerning this assignment should be addressed to Liberty U. Student, 1971 Univeristy Blvd., Lynchburg, VA 24515. Email: [email protected]

SPSS: Reliability Assignment

Table 1 Comment by Swain, Matthew Stephen (Psychology): Be sure to follow APA guidelines for the table. I have basically given you that much here. Be careful when transferring information from SPSS to here.

Cronbach’s Alpha for the Total RBI Scale and Five Subscales

Scale

N

# of Items

Alpha

Disagree

450

10

.94

Mindreading

450

8

.72

Change

449

8

.67

Sexual

444

6

.82

Sexual Differences

442

6

.86

Summary Comment by Swain, Matthew Stephen (Psychology): You will be expected to not simply report the statistics but explain what they mean. Which scale was the worst in terms of reliability? Are there any suggestions you have to improve reliability (i.e., remove certain items or add more items)?

The Relationship Beliefs Inventory (RBI) consisted of five different subscales: (a) disagreement is destructive, (b) mind-reading is expected, (c) partners cannot change, (d) sexual perfectionism, and (e) the sexes are different. Cronbach’s alpha was calculated as a measure of… For the total scale, Cronbach’s alpha was… Alphas for the subscales ranged from… These Alpha values indicated…

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PSYC 515

Homework: Factorial Design SPSS Assignment Instructions

Overview

This worksheet is designed to assess your ability to perform, interpret, report, and graphically present various factorial designs. These are some of the most sophisticated analyses in our field and require practice and thought to perform and interpret. These tests can yield conclusions that change the direction in one’s field. Being able to critically evaluate such results is paramount to maintaining competency in one’s field, and being able to produce such analyses in a competent manner is a coveted skill in our field.

Instructions

Be sure you have reviewed this module’s assigned readings and presentations before completing this assignment. This includes using ensuring the homework is completed and submitted according to the instructions, SPSS output and images are legible and relevant, and that basic college level writing skills (e.g., grammar) are used in the write-ups. Answers should be placed where indicated (e.g., “ANSWER”). Note: all questions must be attempted to be eligible for full credit.

· Please note that for all problems in this course, the standard cut-off (alpha) for a test of significance will be .05, and you always report the exact power unless SPSS output states p=.000 (you’d report p<.001). Also, remember that we divide the p-value in half when reporting one-tailed tests with 1 – 2 groups. Also – remember to check your graphs! You often have to ADD the y – axis title.

· ** remember BS factors are entered into SPSS by having two columns regardless of number of levels. One column is used to identify the levels (e.g., 0 = male; 1 = female), and a second column for the DV values. In contrast, when entering a WS factor, you will have the same number of columns as you do levels, so if you have four levels (e.g., freshman, sophomore, junior, senior), you’d have four columns with the DV values in each per level. See this week’s corresponding SPSS presentation for visual examples.

· One of the examples in your Practice Worksheet for this week explicitly shows how to perform a factorial design with two or more WS factors and no BS factors (although you do have the skills to figure it out without a visual example if you’d like!)

· Submit the file as a WORD document (.doc or .docx). Make sure the filename of your submission includes your full name, course and section.

· Example: SPSS3_JohnDoe_515B01

Scenario 1

Does memory performance differ based on study format (word, picture, and auditory study styles) and/or test format (in person vs. online)? Students in a class (N = 36) were randomly assigned to one of three study conditions (studying lists of words, pictures, or by listening to the list), and randomly assigned to one of two test types (in person or online). This means there were different people in each of the six conditions (n = 6 per condition): word study / in-person test; word study / online test; picture study / in-person test; picture study / online test; auditory study / in-person test; auditory study / online test. Data shown below are percent correct for each of these conditions. Enter it into SPSS to conduct the appropriate analysis and answer the following questions.

STUDY CONDITION