Microsoft Excel is a spreadsheet software that is used to store information in columns and rows, which can then be organized and/or processed. The
primary reason to use Excel for statistical data analysis is because it is so widely available. The t-test and Analysis of Variance (ANOVA) are two of the
statistical methods used to determine if there is any difference in means. The t-test tells us if the mean difference between two groups is significant. ANOVA
is used when determining the difference in means of more than two populations. However, this test can only tell you if there are at least two population
means that are significantly different. Also the hypothesis for analysis of is always a one-tailed test. In this issue, an overview of ANOVA is provided.
The Analysis ToolPak is an add-on that can be
installed for free if you have the installation disk for
Microsoft Office. Getting started with the Analysis
ToolPak:
1. Select Add-Ins from the Tools menu.
2. In the Add-Ins window click on the box next to
Analysis ToolPak to select it.
3. Click OK. You have now installed the Analysis
ToolPak.
Let’s review the research question, hypothesis, the
appropriate statistical method used for the analysis,
and relevant glossary.
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The first step is to enter the test data for the
same students from two classrooms into an
Excel worksheet as illustrated.
The second step is to state the null hypothesis (Ho) and alternative hypothesis (H1). Let µ1 stand
for the mean pretest score, µ2 stand for the mean midterm test score, and µ3 stand for the mean
post-test score. The ANOVA will be used to test the hypotheses where the same students from
two classrooms administered three tests.
The research problem states that the math tutoring program would change the test score so the
alternative hypothesis states not all µ1, µ2, µ3 are equal. Hence Alternative hypothesis in this
study is one-tailed or directional.
Null hypothesis
Ho: µ1 = µ2 = µ3
Alterative hypothesis H1: not all µ1, µ2, µ3 are equal
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The third step: in the Data Analysis window, scroll down and select ANOVA: Single Factor
1. Select or input Range: Enter $B$1:$D$3.
2. Grouped by: Column.
3. Put check mark in front of “labels in first row”
4. Alpha: 0.05
5. Under Output options: Click OK and the results will appear in the new worksheet.
The results
The first table shows the descriptive statistics of
each group and the results indicated unequal variance
The second table is ANOVA table. This table contains information used to calculate F-value.The
only information you will need from this table to test your hypothesis is P-value. In order to
reject the null hypothesis at 95% confidence, you need P-value to be less than or equal to 0.05
You are welcome to contact Jean Chen, Ph.D., Office of Institutional Studies, at [email protected]
or 501-296-1245 for statistical analysis and suggestions.