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Multiple Regression. Using Indicator Variables. Try this …. 1. What is the formula for residual?. 2 . A variable can be either _________ or __________. 3. What is being interpreting with each phrase?. Categorical Variables. So far, we have been working with numerical data .
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Multiple Regression Using Indicator Variables
Try this … 1. What is the formula for residual? 2. A variable can be either _________ or __________. 3. What is being interpreting with each phrase?
Categorical Variables • So far, we have been working with numerical data. • If a variable in a regression is categorical, it is called an _________ / ________ variable. • The dummy variable can be on (__) or off (__).
Ex: Winter Olympics (Vancouver) Using y = number of medals won in 2010 x1 = number of medals won in 2006 x2 = whether or not a country was at home ŷ = 0.1283 + 0.9569x1 + 7.9270x2 s = 1.53 1. Does this regression model suggest that there was a home field advantage?
Ex: Winter Olympics (Vancouver) Using y = number of medals won in 2010 x1 = number of medals won in 2006 x2 = whether or not a country was at home ŷ = 0.1283 + 0.9569x1 + 7.9270x2 s = 1.53 2. Calculate and interpret the residual for Iceland who did not win a single medal.
Ex: Winter Olympics (Vancouver) Using y = number of medals won in 2010 x1 = number of medals won in 2006 x2 = whether or not a country was at home ŷ = 0.1283 + 0.9569x1 + 7.9270x2 s = 1.53 Calculate and interpret the residual for the U.S. which won 25 medals in 2006 and 37 medals in 2010. 3.
Sum it Up • An indicator variableis a _________ explanatory variable with two possible outcomes. These outcomes are coded numerically so they can be included in regression calculations. Typically, a success is reported as a ‘__’ and a failure is recorded as a ‘__’.