110 lines
2.3 KiB
Plaintext
110 lines
2.3 KiB
Plaintext
---
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title: "Assignment 3"
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subtitle: "STAT3373"
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author: "Isaac Shoebottom"
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date: "Oct 2nd, 2025"
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output:
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pdf_document: default
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html_document:
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df_print: paged
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---
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```{r message=FALSE, warning=FALSE}
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library(tidyverse)
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library(broom)
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library(car)
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library(effectsize)
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library(knitr)
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library(kableExtra)
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```
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```{r}
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# Create the fertilizer dataset
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fertilizer_data <- data.frame(
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yield = c(4.2, 4.5, 4.1, 4.8, 4.3, # Fertilizer A
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5.1, 5.3, 4.9, 5.2, 5.0, # Fertilizer B
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3.8, 4.0, 3.6, 4.2, 3.9, # Fertilizer C
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5.5, 5.8, 5.4, 5.7, 5.6), # Fertilizer D
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fertilizer = factor(rep(c("A", "B", "C", "D"), each = 5))
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)
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kable(fertilizer_data, caption = "Tomato Yield Data") %>%
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kable_styling(bootstrap_options = c("striped", "hover"))
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fertilizer_data %>%
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group_by(fertilizer) %>%
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summarise(
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mean = mean(yield),
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sd = sd(yield),
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n = n()
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)
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```
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# Question 1
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## a)
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```{r}
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ggplot(fertilizer_data, aes(x = fertilizer, y = yield)) +
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geom_boxplot(fill = "lightblue") +
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geom_jitter(width = 0.1) +
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labs(title = "Tomato Yield by Fertilizer",
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y = "Yield (kg)",
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x = "Fertilizer")
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```
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Analysis:
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- Fertilizer D appears to produce the highest yields.
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- Fertilizer C appears lowest.
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- Variability is similar across groups.
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## b)
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```{r}
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fertilizer_aov <- aov(yield ~ fertilizer, data = fertilizer_data)
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summary(fertilizer_aov)
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```
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p-value \< 0.05, reject H_0. There is a statistically significant difference in mean yield among fertilizers
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# Question 2
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## a)
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```{r}
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teaching_data <- tibble(
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score = c(78,82,75,80,77,83,79,
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85,88,84,87,86,90,83,
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81,79,83,85,82,78,80),
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method = factor(rep(c("Traditional", "Interactive", "Online"), each = 7))
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)
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```
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## b)
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```{r}
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teaching_aov <- aov(score ~ method, data = teaching_data)
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summary(teaching_aov)
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```
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p-value \< 0.05, reject H_0, significant differences exist.
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# Question 3
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```{r}
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supplier_data <- tibble(
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strength = c(245,250,248,252,249,247,
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240,238,242,241,239,243,
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255,258,254,257,256,253,
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248,246,250,249,247,251),
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supplier = factor(rep(paste("Supplier", 1:4), each = 6))
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)
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supplier_aov <- aov(strength ~ supplier, data = supplier_data)
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summary(supplier_aov)
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```
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p-value \< 0.01, reject H_0, significant differences exist
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