In: Statistics and Probability
Can someone interpret these results especially the test statistic, degree(s) of freedom, p-value, effect size, confidence interval, F statistic and R squared
Note: I have been sending in questions with the same data and no one has been answering.
Gender | Stat Experience | Mean | SD | Min | Max | n |
---|---|---|---|---|---|---|
Male (0) | No Stats Exp (0) | 58.98 | 9.74 | 40.00 | 76.91 | 30 |
Male (0) | Some Stats Exp (1) | 65.43 | 10.87 | 47.53 | 82.04 | 16 |
Female (1) | No Stats Exp (0) | 63.76 | 10.89 | 42.46 | 83.37 | 35 |
Female (1) | Some Stats Exp (1) | 78.78 | 11.52 | 57.69 | 100.00 | 19 |
Model Summary (General Linear Model)
R Squared | R Squared (adj) | F | p.value | df | df residual |
---|---|---|---|---|---|
0.3 | 0.28 | 13.84 | 0 | 3 | 96 |
Coefficient Summary Table
term | estimate | 95% CI Lower | 95% CI Upper | std.error | t | p.value |
---|---|---|---|---|---|---|
(Intercept) | 58.98 | 55.11 | 62.85 | 1.95 | 30.26 | 0.000 |
stat_experienceSome Stats Exp | 6.45 | -0.11 | 13.01 | 3.30 | 1.95 | 0.054 |
genderFemale | 4.78 | -0.50 | 10.05 | 2.66 | 1.80 | 0.075 |
stat_experienceSome Stats Exp:genderFemale | 8.57 | -0.34 | 17.49 | 4.49 | 1.91 | 0.059 |
Model summary(general linear model):
Null Hypothesis (H0):The intercept only model and your model are equal.
Alternative Hypothesis (H1): The intercept only model is reduced significantly compared to your model.
Test statistic, F =13.84 whose p-value at df(numerator) =3 and at df(denominator) =96 is p-value =0.0000. Since p-value < 0.05 significance level, the null hypothesis(H0) is rejected.
Since p-value is very less, there is a strong evidence in favour of the alternative hypothesis. Thus, your model provides a better fit than the intercept only model.
R squared =0.3 =30%. It means 30% of the variation in the dependent variable is explained by the change in the independent variable. This does not consider whether the variable is significant or not.
Adjusted R squared =0.28 =28%. It means 28% of the variation in the dependent variable is explained by the change in the independent variable. This considers only those variables that are significant.
Coefficient Summary Table:
If the confidence interval contains 0, then the variable is not significant. It it does not contain 0, then the variable is significant.
If p-value < 0.05 significance level, the variable is significant. Otherwise, it is not significant.
So, the variables stat_experienceSome Stats Exp, gender Female, stat_experienceSome Stats Exp:gender Female are not significant. Intercept is significant.
Effect is measured by Cohen's d.
d =|M1 - M2|/Sd(pooled)
Where Sd(pooled) =pooled std.deviation =sqrt[(s12 + s22)/2]; M1 and M2 are means of two groups that are being compared.
If d =0.2, the effect size is considered small.
If d =0.5, the effect size is considered medium.
If d =0.8, the effect size is considered large.