Difference between revisions of "Regression Lab In StatCrunch"
From Sean_Carver
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* Do you see outliers in plots. | * Do you see outliers in plots. | ||
* Click on an outlier to turn it pink. | * Click on an outlier to turn it pink. | ||
| − | * Is the outlier an outlier for the other relationship. | + | * Is the outlier an outlier for the other relationship? (x versus y) versus (x versus z). |
* Look at the row in the data set for each outlier. | * Look at the row in the data set for each outlier. | ||
* Can you tell if the data were recorded wrong or if the diamond really had those dimensions? Discuss. | * Can you tell if the data were recorded wrong or if the diamond really had those dimensions? Discuss. | ||
| + | * Repeat for the other outliers. | ||
* Do correlation and regression with the outliers and without the outliers. | * Do correlation and regression with the outliers and without the outliers. | ||
* To do the analyses without the outliers, use Stat, Regression, Simple Linear to Save Residuals. | * To do the analyses without the outliers, use Stat, Regression, Simple Linear to Save Residuals. | ||
* Then use a where function to restrict the data to points with small enough residuals. | * Then use a where function to restrict the data to points with small enough residuals. | ||
Revision as of 16:52, 10 February 2019
Lab 3: Regression, Correlation and Outliers
- We are going to work with the small diamonds data set again: diamonds3K sampled from a larger data set with Codebook.
- We are going to look at the three dimensions of diamonds and how they covary: length (x), width (y), and height (z).
- Make a scatter plot for (x versus y) and separately for (x versus z).
- One of the conditions for correlation and regression is the "No outliers condition."
- Do you see outliers in plots.
- Click on an outlier to turn it pink.
- Is the outlier an outlier for the other relationship? (x versus y) versus (x versus z).
- Look at the row in the data set for each outlier.
- Can you tell if the data were recorded wrong or if the diamond really had those dimensions? Discuss.
- Repeat for the other outliers.
- Do correlation and regression with the outliers and without the outliers.
- To do the analyses without the outliers, use Stat, Regression, Simple Linear to Save Residuals.
- Then use a where function to restrict the data to points with small enough residuals.
