Página de pruebas
Revision as of 21:29, 27 December 2020 by Adelo Vieira (talk | contribs)
Simple Linear Regression
https://www.youtube.com/watch?v=nk2CQITm_eo&t=267s
In general, there are 3 main stages in Linear regression:
- 1. Using Least-squares to fit a line to the data
- 2. Calculating Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle R^2}
- 3. Calculating a for
- 1. Using Least-squares to fit a line to the data
- First, draw a line through the data.
- Second, calculate the Residual sum of squares: Measure the distance from the line to each data point (residual), square each distance, and then add them up.
- The distance from a line to a data point is called a residual
- Then, we rotate the line a little bit and calculate the RSS. We do this many times.
- ...
- Then, the line that represents the linear regression is the one corresponding to the rotation that has the least RSS. The regression equation:
- The equation is composed of 2 parameters:
- Slope:
- The slope is the amount of change in units of for each unitchange in Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle x} .
- The Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle y-axis} intercept: Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle a }
- 2. Calculating Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle R^2}
In the above example, they are using different terminology to the one that we saw in Section Data_Science#The_coefficient_of_determination_R.5E2
It is very important to note how the result of Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle R^2} . In our example There is a 60% reduction in variance when we take the mouse weight into account or Mouse weight "explains" 60% of the variation in mouse size.