```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

```{r}
library(tidyverse)
library(emmeans)
library(multcomp)
```


```{r}
url <- "https://raw.githubusercontent.com/stat720/summer2025/refs/heads/main/data/blood_study_pigs.csv"
df_pigs <- read.csv(url)
unique(df_pigs$Day)
```

```{r}
m1 <- lm(Serum_haptoglobin_mg.dL ~ 1 + Trt + factor(Day) + Trt:factor(Day), data = df_pigs)

plot(m1$fitted.values, m1$residuals)

car::qqPlot(m1)
```

```{r}
summary(m1)
```

```{r}
car::Anova(m1)
```


```{r}
emmeans(m1, ~ Day)

mean_all <- emmeans(m1, ~ Day:Trt)
cld(mean_all)

mean_post <- emmeans(m1, ~ Day:Trt, at = list(Day =38))
cld(mean_post)

```