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Lesson 4: Inferential Statistics and Regression Modeling
7 Comparing the Means of Two Populations < Back | Next >
In many situations we will want to compare two populations parameters. To compare these two populations we can compare the differences between the two sample means.
Example

Lets say we collected the abundance of grass species 1 and 2 one year after a wildfire. We have determined that the two populations had burned under the same exact conditions at the same time etc… Now lets propose that species number 1 will be in higher abundance then species number 2 one year after the fire. This is our research hypothesis. Therefore our null hypothesis will be that there will be no difference in abundance of species 1 and 2

Once we have established our research and null hypothesis we run a test statistic for a given level (assigned as the alpha level). From this point, we can either reject our null hypothesis or not, and then draw any conclusions from the test.

Often times a t-test is used to compare the difference between two means.

Additional Information

t-tests and other statistical analysis

LESSON 4
1 Overview
2 Inferential Statistics
3 Predicting Population
4 Using a confidence interval
5 Hypothesis Testing
6 One and Two Tailed Tests
7 Comparing the Means
8 ANOVA or Analysis of Variance
9 Multiple Comparison Procedures
10 Regression Models & Correlation
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