Spss
Essay by review • February 23, 2011 • Term Paper • 1,264 Words (6 Pages) • 1,043 Views
Introduction
This paper reports and analyses the findings of a questionnaire about TV viewing. There are eight variables to the questionnaire and these variables are a variety of scales of measurement.
Descriptive statistics provide important information about variables. Mean, median and mode measure central tendency of a variable. Although normal distribution is often assumed, that is not always the case. Graphical methods to test normality allow visualization and comparison of the distribution of a random variable. These methods are both descriptive and theory oriented. This study incorporates graphical methods, both descriptive; Stem-and-leaf plot, box plot, Histogram, and Theory; Q-Q plot.
All statistics, graphs, and cross-tabulations were prepared using the SPSS software. The data was collected on February 8, 2008 and is based on actual responses from respondents that are associated with the author.
TV hours
Descriptive Statistics
(1) Descriptive Statistics (Also, calculate the coefficient of variation)
Statistics
TV
N Valid 59
Missing 0
Variance 117.895
TV
Frequency Percent Valid Percent Cumulative Percent
Valid 2 2 3.4 3.4 3.4
5 7 11.9 11.9 15.3
6 3 5.1 5.1 20.3
7 1 1.7 1.7 22.0
8 3 5.1 5.1 27.1
10 15 25.4 25.4 52.5
14 1 1.7 1.7 54.2
15 4 6.8 6.8 61.0
17 1 1.7 1.7 62.7
20 5 8.5 8.5 71.2
21 1 1.7 1.7 72.9
22 1 1.7 1.7 74.6
23 1 1.7 1.7 76.3
24 3 5.1 5.1 81.4
25 1 1.7 1.7 83.1
26 1 1.7 1.7 84.7
28 2 3.4 3.4 88.1
30 1 1.7 1.7 89.8
33 1 1.7 1.7 91.5
38 1 1.7 1.7 93.2
40 1 1.7 1.7 94.9
42 2 3.4 3.4 98.3
43 1 1.7 1.7 100.0
Total 59 100.0 100.0
Descriptive Statistics
N Minimum Maximum Mean Std. Deviation
TV 59 2 43 15.97 10.858
Valid N (listwise) 59
(2) Histogram (Superimpose the normal curve over the histogram)
(3) Stem- and- Leaf
Hours Stem-and-Leaf Plot
Frequency Stem & Leaf
2.00 0 . 22
14.00 0 . 55555556667888
16.00 1 . 0000000000000004
5.00 1 . 55557
11.00 2 . 00000123444
4.00 2 . 5688
2.00 3 . 03
1.00 3 . 8
4.00 4 . 0223
Stem width: *
Each leaf: 1 case(s)
(4) Box Plot
(5) Test the normality of distribution (One of the methods is QQ plot)
By looking at the descriptive statistics charts, we can see that the average hours of TV watched per week (mean) is 15.97. This is due to the fact the highest frequency of TV hours is between 2 and 20 hours a week. The histogram provides us with a graphic view of the data. We can see that the bars are skewed to the left, and it is evident that most of the observations are to the left of the mean. If a variable is normally distributed, its median and mean are located at the same point exactly in the center of the box plot, and the 1st and 3rd quartiles are symmetric. This is not true with our data. It can be concluded that the hours of TV watched per week is not normally distributed.
Age
(1) Descriptive Statistics (Also, calculate the coefficient of variation)
Statistics
Age
N Valid 59
Missing 0
Descriptive Statistics
N Minimum Maximum Mean Std. Deviation
Age 59 18 90 33.58 13.472
Valid N (listwise) 59
Age
Frequency Percent Valid Percent Cumulative Percent
Valid 18 2 3.4 3.4 3.4
19 3 5.1 5.1 8.5
22 1 1.7 1.7 10.2
23 4 6.8 6.8 16.9
24 2 3.4 3.4 20.3
25 6 10.2 10.2 30.5
26 5 8.5 8.5 39.0
27 1 1.7 1.7 40.7
28 2 3.4 3.4 44.1
29 3 5.1 5.1 49.2
30 3 5.1 5.1 54.2
32 1 1.7 1.7 55.9
33 3 5.1 5.1 61.0
34 1 1.7 1.7 62.7
35 4 6.8 6.8 69.5
36 2 3.4 3.4 72.9
37 1 1.7 1.7 74.6
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