Advance Biostats SPSS (Two-Way ANOVA) Use Tukey

PART 1

Step-by-Step Guide Assignment Problem 3.1

2-Way ANOVA

Problem 1. Provide numeric descriptive statistics (include skewness and kurtosis if appropriate) and graphic descriptions for Sex, Educ, and Exercise.

Step 1. Open the practice data set Practice_WK3_dataset.sav in SPSS.

Step 2. In Variable View, note that data for EXERCISE are scale (interval or ratio) level measurments. Education and Sex are nominal level.

Step 3. For the nominal level variables (EDUC and SEX), run frequencies. Go to Analyze ( Descriptive Statistics ( Frequencies.

Step 4. In the storage box on the left in the Frequencies window, click once on Sex [SEX] to highlight the variable. Click the arrow next to the box to transfer it to the Variable(s) box.

Step 5. Repeat Step 4 to transfer EDUC to Variable(s).

Step 6. Click on the Charts button. In the Frequencies: Charts window, move the radio button to Bar Charts.

Step 7. Click Continue then click OK.

The following should be displayed in your SPSS Output:

Statistics
	Sex	Education level
N	Valid	100	100
	Missing	0	0

The data set includes sex and education level information on 100 participants. There are no missing data.

Sex
	Frequency	Percent	Valid Percent	Cumulative Percent
Valid	Male	49	49.0	49.0	49.0
	Female	51	51.0	51.0	100.0
	Total	100	100.0	100.0

Sex is a dichotomous variable (two levels: male and female). The data set is comprised of 49% (n = 49) males and 51% (n = 51) females.

The bar chart shows that there are approximately equal proportions of males and females.

Education level
	Frequency	Percent	Valid Percent	Cumulative Percent
Valid	No or some high school	16	16.0	16.0	16.0
	High school diploma	31	31.0	31.0	47.0
	College Degree	53	53.0	53.0	100.0
	Total	100	100.0	100.0

There are three levels of education: 16 (16%) participants have either no or some high school education; 31 (31%) have a high school diploma and 53 (53%) have a college degree.

The bar chart shows the proportional distribution of education levels. There are almost twice as many participants with a high school diploma as with no or some high school. There are almost twice as many with a college degree as with a high school diploma.

Step 8. Go to Analyze ( Descriptive Statistics ( Frequencies. (Note that you do not need to switch back to Variable View.)

Step 9. Click Reset in the Frequencies window to clear the input.

Step 10. Transfer Steps per month [EXERCISE] to the Variable(s) box. Since EXERCISE is a continuous variable, click Statistics.

Step 11. Check Mean, Std. deviation, Minimum, Maximum, Skewness, and Kurtosis as below. Click Continue.

Step 12. Click Charts.

Step 13. Select Histograms and check Show normal curve on histogram.

Step 14. Click OK to run the analysis and graphics for EXERCISE.

SPSS Output:

Statistics
Steps per month
N	Valid	100
	Missing	0
Mean	26770.40
Std. Deviation	18131.702
Skewness	1.102
Std. Error of Skewness	.241
Kurtosis	1.097
Std. Error of Kurtosis	.478
Minimum	1000
Maximum	82700

There are no missing data. The mean steps per month is 26,770.4 with a range of 1,000 to 82,700 steps. The standard deviation is 18,131.7. There is a somewaht positive skew and kurtosis is close to 1.0.

The histogram shows that the distribution of EXERCISE deviates from normal with a positive skew and steeper kurtosis.

Export the SPSS Output to a Word document and Save. See Week 1, Steps 11 – 14. Then close out the Output window.