Please help me interpret the following results.
The full model (Schwa~Dialect*Prediction*Reduction) was reduced via both
update() and step().
The minimal adequate model is:
ancova<-lm(Schwa~Dialect+Prediction+Reduction+Dialect:Prediction)

Schwa is response variable
Dialect is factor, two levels ("QF","SF")
Prediction is factor, two levels ("High","Low")
Reduction is covariate

summary(ancova) yields:

Coefficients:
                        Estimate Std. Error t value Pr(>|t|)
(Intercept)              0.58047    0.09865   5.884    9e-07 ***
DialectSF               -0.11819    0.08513  -1.388 0.173315
PredictionLow           -0.49309    0.13650  -3.612 0.000896 ***
Reduction               -0.53488    0.15354  -3.484 0.001289 **
DialectSF:PredictionLow  0.49494    0.14627   3.384 0.001703 **

I know that the (Intercept) is the intercept for the first levels of both
factors (QF.High)
I know that Reduction is the slope for the first levels of both factors
(QF.High)

What i don't know is:
Is DialectSF the difference in intercepts between QF.High and SF.High?
Is PredictionLow the difference in intercepts between QF.High and QF.Low?
Is DialectSF:PredictionLow the difference in slope from Reduction?
If it's the slope, how do I find out the intercept?

With 2X2 factors and one interaction term, how many parameters am I
estimating? One slope and 4 intercepts? Or 3 intercepts and 2 slopes?

Thanks,
Peter

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