Aresearcher evaluates the significance of a multiple-regression equation and obtains an f-ratio with df = 2,24. how many participants were in the sample?

N=27 participants

Step-by-step explanation:

Analysis of variance (ANOVA) "is used to analyze the differences among group means in a sample".  

The sum of squares "is the sum of the square of variation, where variation is defined as the spread between each individual value and the grand mean"  

When we conduct a multiple regression we want to know about the relationship between several independent or predictor variables and a dependent or criterion variable.

If we assume that we have independent variables and we have   individuals, we can define the following formulas of variation:  

And we have this property  

The degrees of freedom for the model on this case is given by where k =2 represent the number of variables.

The degrees of freedom for the error on this case is given by . Sinc we know k we can find N.

And the total degrees of freedom would be

On this case the correct answer would be N=27 participants

answer: what in the world is this

step-by-step explanation: