In: Statistics and Probability
A sales manager is interested in determining the relationship between the amount spent on advertising and total sales. the manger collects data for the past months and runs a regression of sales on advertising expenditures. The results wıth some missing values are presented below.
Regression Statistics |
|
Multiple R R Square Adjusted R Square Standard Error Observations |
0.492 0.242 0.208 40.975 |
ANOVA |
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df |
SS |
MS |
F |
Significance |
|
Regression Residual Total |
1 |
Coefficients |
Standard Error |
t Stat |
P-value |
|
Constant Advertising |
To test the significance of the regression what is the test statistic value?
It is given that F value = 7.034. Presently we need to ascertain degrees of opportunity for numerator and denominator.
Degrees of freedom for numerator = k - 1 where k = number of parameters = 2(intercept and advertising).
Along these lines, Degrees of freedom for numerator = k - 1 = 2 - 1 = 1
Degrees of opportunity for denominator = n - k where k = number of boundaries = 2 and n = number of perceptions = 24.
Along these lines, Degrees of opportunity for denominator = 24 - 2 = 22
Hence forth Using F table with above degrees of opportunity we have F critical for centrality = 0.01 is 7.945 and subsequently P value must be more noteworthy than 0.01 in light of the fact that f critical is lesser than f significance = 0.01.
Utilizing F table with above degrees of freedom we have F critical for centrality = 0.05 is 4.3009 and in this manner P esteem must be lesser than 0.05 in light of the fact that f basic is more than f significance determined at significance = 0.05.
Thus P value is somewhere in the range of 0.01 and 0.05
Thus, the right answer is (B) Smaller than 0.05.
2)
t statistic in regression = Parameter value/Standard error
Here,
t statistic = 2.652 Parameter value = 2.015 and we need to ascertain Standard blunder.
Thus Using above formula we have : Standard blunder = Parameter esteem/t measurement = 2.015/2.652 = 0.76
Thus, the right answer is (B) 0.76