SPSS: Descriptive Statistics of Central Tendency and Variability - Paper Example

Imagine a researcher is interested in examining the psychological impact of principals perceived conflict management style on teachers productivity. In this case, the researcher is interested in the relationships among teachers self-esteem, how teachers perceive their principals conflict management style, and teachers productivity in a convenience sample of 40 teachers. These teachers completed a survey including a number of demographic questions as well as measures to assess perceived principals conflict management style, teachers self-esteem, and productivity. Below are the demographic questions and participants responses. Use these data to complete the questions below (these data have already been entered into the teachersurvey.sav SPSS data file).

NOTE: Not all of the variables in the teachersurvey.sav data file will be used for this assignment.

What is your gender (M = male, F = female)? What is your age (in years)? How long have you been teaching (in years)? What topic do you teach (M = math, S = science, A = art, FL = foreign language)? How many students are in your class?

M 52 25 M 18

M 35 14 M 23

F 45 10 A 27

M 47 20 S 21

F 62 30 S 21

F 29 2 A 29

F 50 23 FL 25

F 43 13 A 31

M 54 29 S 24

M 40 19 S 25

F 44 22 S 32

F 53 5 M 30

F 56 16 M 19

F 28 11 S 28

M 51 15 S 21

M 30 2 FL 22

F 45 15 A 27

M 36 11 M 29

F 57 18 S 30

M 58 10 S 20

M 59 21 A 27

M 34 5 S 23

F 48 18 S 33

F 50 21 M 19

M 57 17 FL 15

F 48 15 FL 21

M 39 18 S 24

M 36 12 M 26

F 29 8 A 23

M 52 3 A 24

F 68 33 S 28

F 45 16 A 25

F 56 29 FL 26

M 40 19 M 20

F 33 4 M 23

F 47 17 S 27

M 58 30 A 25

M 49 20 FL 27

F 39 11 M 30

F 42 14 FL 22

Part of the goal of this assignment is to explore the various tools under the ANALYZE tab in SPSS to become more comfortable with these features.

In this SPSS assignment, you will increase your understanding of descriptive statistics involving central tendency and variability of data.

Split the file by gender. Calculate the mean and standard deviation of age and number of years teaching (experience) for males and females. Hint: use Explore found under the ANALSYS => Descriptives tabs. Age and Experience will be the dependent variable and Gender will be the factor.

Male teachers age mean is 45.94 and male teachers years of teaching (experience) mean is 16.11.

Male teachers age standard deviation is 9.674 and male teachers experience standard deviation is 8.021.

Female teachers age mean is 46.23 and female teachers experience mean is 15.95.

Female teacher age standard deviation is 10.470 and female teachers experience standard deviation is 8.162.

Descriptive Statistics

1=male, 2=female N Minimum Maximum Mean Std. Deviation

1 Age 18 30 59 45.94 9.674

Experience 18 2 30 16.11 8.021

Valid N (listwise) 18 2 Age 22 28 68 46.23 10.470

Experience 22 2 33 15.95 8.162

Valid N (listwise) 22 Compute the mean, median, and mode for number of students in the class (class size). What value is the most representative measure of the central tendency for this variable and why?

Class size mean is 24.75, median is 25.00, and mode is 27. The median is the most representative measure of central tendency for this variable because extreme values in the data set do not affect it. In addition, the mean in this data set is close to the media, and the mode, which suggests that the data set has low variability. Low variability ameliorates the main limitation of the median the medians failure to include all values in a data set.

Statistics

ClassSize

N Valid 40

Missing 0

Mean 24.75

Median 25.00

Mode 27

ClassSize

Frequency Percent Valid Percent Cumulative Percent

Valid 15 1 2.5 2.5 2.5

18 1 2.5 2.5 5.0

19 2 5.0 5.0 10.0

20 2 5.0 5.0 15.0

21 4 10.0 10.0 25.0

22 2 5.0 5.0 30.0

23 4 10.0 10.0 40.0

24 3 7.5 7.5 47.5

25 4 10.0 10.0 57.5

26 2 5.0 5.0 62.5

27 5 12.5 12.5 75.0

28 2 5.0 5.0 80.0

29 2 5.0 5.0 85.0

30 3 7.5 7.5 92.5

31 1 2.5 2.5 95.0

32 1 2.5 2.5 97.5

33 1 2.5 2.5 100.0

Total 40 100.0 100.0 Calculate the range of number of years teaching (experience). What does this information indicate about the years of experience?

The minimum experience is 2 years, whereas the maximum experience is 33 years, which makes the range of experience 31 years; this information indicates a wide variation in the experience of the teachers who participated in the survey.

Case Processing Summary

Cases

Valid Missing Total

N Percent N Percent N Percent

Experience 40 100.0% 0 0.0% 40 100.0%

Descriptives

Statistic Std. Error

Experience Mean 16.03 1.264

95% Confidence Interval for Mean Lower Bound 13.47 Upper Bound 18.58 5% Trimmed Mean 15.94 Median 16.00 Variance 63.922 Std. Deviation 7.995 Minimum 2 Maximum 33 Range 31 Interquartile Range 10 Skewness .151 .374

Kurtosis -.363 .733

Experience

Experience Stem-and-Leaf Plot

Frequency Stem & Leaf

4.00 0 . 2234

3.00 0 . 558

9.00 1 . 001112344

12.00 1 . 555667788899

6.00 2 . 001123

3.00 2 . 599

3.00 3 . 003

Stem width: 10

Each leaf: 1 case(s)

Create a frequency distribution graph for topics taught. What is the most appropriate measure of central tendency? Report this value (the appropriate measure of central tendency for this variable). What is the appropriated graphical representation of the frequency distribution? Using SPSS, generate the graphical representation selected combined with supported answers.

The most appropriate measure of central tendency for experience is the mean because it includes all values in a data set, and, in this case, the mean and median are not significantly different. The mean experience is 16.03 years. The appropriate graphical representation of the frequency distribution is the box plot. The following figure shows the box plot this figure shows that the minimum experience is 2 years, the lower quartile is 11 years, the median is 16 years, the upper quartile is 21 years, and the maximum experience is 33 years.

Statistics

1=math,2=science,3=art,4=foreign language

N Valid 40

Missing 0

Mean 2.33

Median 2.00

Mode 2

1=math,2=science,3=art,4=foreign language

Frequency Percent Valid Percent Cumulative Percent

Valid 1 10 25.0 25.0 25.0

2 14 35.0 35.0 60.0

3 9 22.5 22.5 82.5

4 7 17.5 17.5 100.0

Total 40 100.0 100.0