# How to interpret glm output for quasi-binomial model

I am having difficulty interpreting the output for a quasibinomial model.

My first issue is that I have used the function 'autoplot' to test assumptions, and the normal Q-Q plot is skewed:

I am unsure whether or not it is okay to proceed with fitting the anova, or how to adjust my data if it is not ok to proceed.

Assuming that it was okay to proceed, when running the anova there is a significant effect of 'Group' (using a critical p-value of 0.05). However, there are no significant effects found in the output when using the summary function. How would I interpret this, or write this result in a report?


Efetphagoquasi <- glm(cbind(NumPhago,NumNotPhago)~Group*Day, data = Efet, family = "quasibinomial")

autoplot(Efetphagoquasi, smooth.colour = NA)

summary(Efetphagoquasi)

Call:
glm(formula = cbind(NumPhago, NumNotPhago) ~ Group * Day, family = "quasibinomial",
data = Efet)

Deviance Residuals:
Min        1Q    Median        3Q       Max
-10.2932   -4.5115   -0.4734    3.9493   10.7405

Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept)          -0.25131    0.35544  -0.707    0.483
GroupTreatment       -0.03054    0.50317  -0.061    0.952
Day14                -0.10749    0.50472  -0.213    0.832
Day28                 0.30633    0.50079   0.612    0.544
GroupTreatment:Day14 -1.30657    0.78674  -1.661    0.104
GroupTreatment:Day28 -0.72701    0.71971  -1.010    0.318

(Dispersion parameter for quasibinomial family taken to be 24.87212)

Null deviance: 1443.3  on 47  degrees of freedom
Residual deviance: 1157.4  on 42  degrees of freedom
AIC: NA

Number of Fisher Scoring iterations: 5

anova(Efetphagoquasi, test="F")

Analysis of Deviance Table

Response: cbind(NumPhago, NumNotPhago)

Terms added sequentially (first to last)

Df Deviance Resid. Df Resid. Dev      F  Pr(>F)
NULL                         47     1443.3
Group      1  113.280        46     1330.0 4.5545 0.03871 *
Day        2  100.189        44     1229.8 2.0141 0.14613
Group:Day  2   72.481        42     1157.4 1.4571 0.24445
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1


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