Is this a variation on a residual plot?

Thread starter Ikaros
Start date May 4, 2014
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Plot Variation

In summary, a residual plot is a graph used in regression analysis to show the difference between observed and predicted values. It differs from a scatter plot in that it specifically focuses on the residuals. It is used to check the assumptions of the model, assess the overall fit, and identify any potential issues with the data. The points on a residual plot represent the difference between the actual and predicted values, with positive residuals indicating higher observed values and negative residuals indicating lower observed values. A random distribution of points around the horizontal line at 0 is ideal, but patterns or outliers may suggest problems with the model or data.

May 4, 2014

Ikaros

Hi all,

Consider the scatter plot below (example only):

The bottom subplot looks like a residual plot (y-x), but it's over (1+x). I'm hoping someone can explain what this is and the benefit of it.

Thanks

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May 5, 2014

mfb

Mentor

Insights Author

Maybe the uncertainty is expected to scale with 1+x?

May 5, 2014

Ikaros

Based on what type of data it is, I think you're correct. Thanks.

1. What is a residual plot?

A residual plot is a graph that shows the difference between the observed values and the predicted values in a regression analysis. It is used to detect patterns and identify any outliers or unusual data points in the data set.

2. How is a residual plot different from a scatter plot?

A scatter plot shows the relationship between two variables, while a residual plot shows the difference between the actual values and the predicted values. A scatter plot is used to visualize the overall pattern of the data, while a residual plot is used to identify any patterns or outliers in the data set.

3. When should I use a residual plot?

A residual plot should be used after conducting a regression analysis to check the assumptions of the model. It can also be used to assess the overall fit of the model and identify any potential issues with the data.

4. What do the points on a residual plot represent?

The points on a residual plot represent the difference between the actual values and the predicted values. A positive residual means that the observed value is higher than the predicted value, while a negative residual means that the observed value is lower than the predicted value.

5. How do I interpret a residual plot?

A residual plot should show a random distribution of points around the horizontal line at 0. If there is a clear pattern or trend in the points, it may indicate that the model is not appropriate for the data set. Outliers or clusters of points may also suggest that there are issues with the data.