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# List of packages
packages <- c("tidyverse", "fst", "modelsummary") # add any you need here
# Install packages if they aren't installed already
new_packages <- packages[!(packages %in% installed.packages()[,"Package"])]
if(length(new_packages)) install.packages(new_packages)
# Load the packages
lapply(packages, library, character.only = TRUE)
## ── Attaching core tidyverse packages ──────────────────────── tidyverse 2.0.0 ──
## ✔ dplyr 1.1.4 ✔ readr 2.1.5
## ✔ forcats 1.0.0 ✔ stringr 1.5.1
## ✔ ggplot2 3.4.4 ✔ tibble 3.2.1
## ✔ lubridate 1.9.3 ✔ tidyr 1.3.0
## ✔ purrr 1.0.2
## ── Conflicts ────────────────────────────────────────── tidyverse_conflicts() ──
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag() masks stats::lag()
## ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors
## [[1]]
## [1] "lubridate" "forcats" "stringr" "dplyr" "purrr" "readr"
## [7] "tidyr" "tibble" "ggplot2" "tidyverse" "stats" "graphics"
## [13] "grDevices" "utils" "datasets" "methods" "base"
##
## [[2]]
## [1] "fst" "lubridate" "forcats" "stringr" "dplyr" "purrr"
## [7] "readr" "tidyr" "tibble" "ggplot2" "tidyverse" "stats"
## [13] "graphics" "grDevices" "utils" "datasets" "methods" "base"
##
## [[3]]
## [1] "modelsummary" "fst" "lubridate" "forcats" "stringr"
## [6] "dplyr" "purrr" "readr" "tidyr" "tibble"
## [11] "ggplot2" "tidyverse" "stats" "graphics" "grDevices"
## [16] "utils" "datasets" "methods" "base"
# List of packages
packages <- c("tidyverse", "infer", "fst") # add any you need here
# Install packages if they aren't installed already
new_packages <- packages[!(packages %in% installed.packages()[,"Package"])]
if(length(new_packages)) install.packages(new_packages)
# Load the packages
lapply(packages, library, character.only = TRUE)
## Warning: package 'infer' was built under R version 4.3.3
## [[1]]
## [1] "modelsummary" "fst" "lubridate" "forcats" "stringr"
## [6] "dplyr" "purrr" "readr" "tidyr" "tibble"
## [11] "ggplot2" "tidyverse" "stats" "graphics" "grDevices"
## [16] "utils" "datasets" "methods" "base"
##
## [[2]]
## [1] "infer" "modelsummary" "fst" "lubridate" "forcats"
## [6] "stringr" "dplyr" "purrr" "readr" "tidyr"
## [11] "tibble" "ggplot2" "tidyverse" "stats" "graphics"
## [16] "grDevices" "utils" "datasets" "methods" "base"
##
## [[3]]
## [1] "infer" "modelsummary" "fst" "lubridate" "forcats"
## [6] "stringr" "dplyr" "purrr" "readr" "tidyr"
## [11] "tibble" "ggplot2" "tidyverse" "stats" "graphics"
## [16] "grDevices" "utils" "datasets" "methods" "base"
#Task 1 #Based on the recoding of lrscale for “left” and “right” and omitting “moderates” (see Tutorial 4), and educ.ba from this tutorial, do the long form coding for Chi-Square. Using the steps outlined in the tutorial, first generate the tables of expected proportions and frequencies. Determine and interpret the critical value for independence. Finally, determine and interpret both the Pearson’s chi-squared statistic and the p-value. Discuss main takeaways.
getwd()
## [1] "C:/Users/User/Downloads"
france_data <- read.fst("france_data.fst")
france_data <- read.fst("france_data.fst") %>%
# Filter for France
filter(cntry == "FR") %>%
# Recoding clsprty and cleaning trstplt (will use later)
mutate(
clsprty = case_when(
clsprty == 1 ~ "Yes", # Recode 1 to "Yes"
clsprty == 2 ~ "No", # Recode 2 to "No"
clsprty %in% c(7, 8, 9) ~ NA_character_, # Handle other specific cases where you want to set it as NA
TRUE ~ as.character(clsprty) # Keep other values as-is but ensure they are characters
),
trstplt = ifelse(trstplt %in% c(77, 88, 99), NA, trstplt),
# Recoding gender
gndr = case_when(
gndr == 1 ~ "Male",
gndr == 2 ~ "Female",
gndr == 9 ~ NA_character_,
TRUE ~ as.character(gndr)
),
# Recoding education with case_when for consistency
educ.ba = case_when(
essround < 5 & edulvla == 5 ~ "BA or more",
essround >= 5 & edulvlb > 600 ~ "BA or more",
TRUE ~ "No BA"
)
) %>%
# Ensure all NAs are handled uniformly
mutate(
edulvla = ifelse(edulvla %in% c(77, 88), NA_integer_, edulvla),
edulvlb = ifelse(edulvlb %in% c(5555, 7777, 8888), NA_integer_, edulvlb),
educ.ba = as.character(educ.ba) # Force educ.ba to be treated as character
)
unique(france_data$gndr)
## [1] "Female" "Male"
unique(france_data$clsprty)
## [1] "Yes" "No" NA
france_data <- france_data %>% filter(!is.na(clsprty))
france_data <- france_data %>% filter(!is.na(trstplt))
# double-checking + quick distribution
unique(france_data$clsprty)
## [1] "Yes" "No"
table(france_data$clsprty)
##
## No Yes
## 9098 9480
france_clean <- france_data %>%
mutate(
clsprty = ifelse(clsprty == 2, 0, ifelse(clsprty %in% c(7, 8, 9), NA, clsprty)), # If 'clsprty' is 2, set it to 0. If it's 7, 8, or 9, set it to NA.
stfdem = ifelse(stfdem %in% c(77, 88, 99), NA, stfdem), # For 'stfdem', set values 77, 88, and 99 to NA.
trstplt = ifelse(trstplt %in% c(77, 88, 99), NA, trstplt), # For 'trstplt', set values 77, 88, and 99 to NA.
)
france_clean <- france_clean %>% filter(!is.na(clsprty), !is.na(stfdem), !is.na(trstplt))
france_clean <- france_clean %>%
mutate(
# Recoding 'lrscale' into a new variable 'ID'
ID = case_when(
lrscale %in% 0:3 ~ "Left", # Values 0 to 3 in 'lrscale' are categorized as "Left"
lrscale %in% 7:10 ~ "Right", # Values 7 to 10 in 'lrscale' are categorized as "Right"
lrscale %in% 4:6 ~ "Moderate", # Values 4 to 6 in 'lrscale' are categorized as "Moderate"
lrscale %in% c(77, 88, 99) ~ NA_character_ # Values 77, 88, 99 in 'lrscale' are set as NA
),
# Recoding 'yrbrn' (year born) into a new variable 'Gen'
Gen = case_when(
yrbrn %in% 1900:1945 ~ "1", # Birth years from 1900 to 1945 categorized as "1"
yrbrn %in% 1946:1964 ~ "2", # Birth years from 1946 to 1964 categorized as "2"
yrbrn %in% 1965:1979 ~ "3", # Birth years from 1965 to 1979 categorized as "3"
yrbrn %in% 1980:1996 ~ "4", # Birth years from 1980 to 1996 categorized as "4"
TRUE ~ as.character(yrbrn) # Other years remain unchanged
),
# Converting 'Gen' to a factor with meaningful labels
Gen = factor(Gen, levels = c("1", "2", "3", "4"),
labels = c("Interwar", "Baby Boomers", "Gen X", "Millennials")) # Assigning labels to the levels in 'Gen'
)
tab_dat <- france_data
# Create a crosstable and save it into the object mytab
mytab <- table(tab_dat$clsprty, tab_dat$educ.ba)
# Calculate row-wise sums of counts in table
rsums <- rowSums(mytab)
# Calculate column-wise sums of counts in table
csums <- colSums(mytab)
# Get the total count of the table (N)
N <- sum(mytab)
# Generate table of expected proportions
ptab <- tcrossprod(rsums/N, csums/N)
cat("Table of Expected Proportions:\n")
## Table of Expected Proportions:
print(ptab)
## [,1] [,2]
## [1,] 0.1099746 0.3797444
## [2,] 0.1145921 0.3956889
# Table of expected frequencies
ftab <- N * ptab
cat("Table of Expected Frequencies:\n")
## Table of Expected Frequencies:
print(ftab)
## [,1] [,2]
## [1,] 2043.108 7054.892
## [2,] 2128.892 7351.108
# Critical Value for Independence:
alpha <- 0.05 # significance level
c_val <- qchisq(alpha, df = 1, lower.tail = FALSE)
cat("Critical Value:", round(c_val, 3), "\n")
## Critical Value: 3.841
# Pearson's chi-squared statistic:
test_stat <- sum((mytab - ftab)^2 / ftab)
cat("Pearson's X^2:", round(test_stat, 4), "\n")
## Pearson's X^2: 160.4057
# p-value:
p_val <- pchisq(test_stat, df = 1, lower.tail = F)
cat("p-value:", round(p_val, 4), "\n")
## p-value: 0
# Using chisq.test for validation:
cat("Chi-squared test result:\n")
## Chi-squared test result:
print(chisq.test(mytab, correct = F))
##
## Pearson's Chi-squared test
##
## data: mytab
## X-squared = 160.41, df = 1, p-value < 2.2e-16
#Answer:
#Task 2 #Do Steps 1 to 3 using the infer package (as we did in the tutorial), for the variables sbbsntx (recoded to the corresponding 5 categories) as the response and domicil (recoded to urban and rural, setting 2 to urban instead of peri-urban) as the explanatory variable for the country of France.
france_data <- read.fst("france_data.fst")
test_stat <- france_data %>%
specify(explanatory = domicil, # change variable name for explanatory variable
response = sbbsntx) %>% # change variable name for outcome of interest
hypothesize(null = "independence") %>%
calculate(stat = "slope") # replace in between quotation marks appropriate test statistic
## Warning: Removed 14895 rows containing missing values.
## Message: The independence null hypothesis does not inform calculation of the
## observed statistic (a slope) and will be ignored.
print(test_stat$stat)
## domicil
## -0.0788481
#Interpretation: A slope of -0.0788 suggests that there isn’t enough informstion about the relationship between the variables. The negavtive number represents a negative relationship between the two variables. If one variable increases, the other decreases.
null_distribution <- france_data %>%
specify(explanatory = domicil,
response = sbbsntx) %>%
hypothesize(null = "independence") %>%
generate(reps = 1000, type = "permute") %>% # only line we are adding, use reps = 1000 as standard but change if too computationally demanding
calculate(stat = "slope")
## Warning: Removed 14895 rows containing missing values.
p_val <- null_distribution %>% # replace name here if you assigned something other than null_distribution above
get_pvalue(obs_stat = test_stat, direction = "two-sided") # would only replace test_stat if assigned another name in Step 1
## Warning: Please be cautious in reporting a p-value of 0. This result is an approximation
## based on the number of `reps` chosen in the `generate()` step.
## ℹ See `get_p_value()` (`?infer::get_p_value()`) for more information.
p_val
## # A tibble: 1 × 1
## p_value
## <dbl>
## 1 0
#interpreation of p-value: Since our p-value is smaller than 0.05, it suggests strong evidence against the null hypothesis, therefore we reject it.
#Task 3 #Now do Step 4 (i.e., the null distribution visualization with confidence intervals) for the same variables and country as Task 2, and interpret the output.
null_distribution %>%
visualize() +
shade_p_value(obs_stat = test_stat, direction = "two-sided")
null_distribution
## Response: sbbsntx (numeric)
## Explanatory: domicil (numeric)
## Null Hypothesis: independence
## # A tibble: 1,000 × 2
## replicate stat
## <int> <dbl>
## 1 1 0.00245
## 2 2 -0.0256
## 3 3 0.0173
## 4 4 -0.0209
## 5 5 0.00118
## 6 6 0.0267
## 7 7 0.0340
## 8 8 0.00770
## 9 9 0.00715
## 10 10 0.0124
## # ℹ 990 more rows
#Interpreation: The values here some have a larger value than 0.05 and some have a smaller one therefore some suggest strong eveidence to reject the null hypothesis while others do not.
conf_int <- null_distribution %>%
get_confidence_interval(level = 0.95, type = "percentile")
null_distribution %>%
visualize() +
shade_p_value(obs_stat = test_stat, direction = "two-sided") +
shade_confidence_interval(endpoints = conf_int)
null_distribution
## Response: sbbsntx (numeric)
## Explanatory: domicil (numeric)
## Null Hypothesis: independence
## # A tibble: 1,000 × 2
## replicate stat
## <int> <dbl>
## 1 1 0.00245
## 2 2 -0.0256
## 3 3 0.0173
## 4 4 -0.0209
## 5 5 0.00118
## 6 6 0.0267
## 7 7 0.0340
## 8 8 0.00770
## 9 9 0.00715
## 10 10 0.0124
## # ℹ 990 more rows
#Task 4 #Conduct Steps 1 to 3 using the infer package (as we did in the tutorial), for the variables ccrdprs (leaving it on the 0-10 numeric scale) as the response (or outcome) variable and lrscale (recoded as left and right, omitting “moderates” as we did in Task 1) as the explanatory variable.
table(france_data$ccrdprs)
##
## 0 1 2 3 4 5 6 7 8 9 10 66 77 88 99
## 72 26 64 78 114 478 403 736 952 358 708 27 1 29 1
table(france_data$lrscale)
##
## 0 1 2 3 4 5 6 7 8 9 10 77 88
## 945 499 1269 1996 1838 5274 1594 1749 1458 409 686 381 940
france_data <- france_data %>%
mutate(
ccrdprs = ifelse(ccrdprs %in% c(66:99), NA, ccrdprs)
)
france_data <- france_data %>%
filter(!is.na(ccrdprs) & !is.na(lrscale))
france_data <- france_data %>%
mutate(
lrscale = factor(lrscale)
)
france_data <- france_data %>%
mutate(lrscale = ifelse(lrscale %in% 77:99, NA, lrscale)) %>%
filter(!lrscale %in% 4:6) %>%
mutate(
lrscale = case_when(
lrscale %in% 0:3 ~ "Left",
lrscale %in% 7:10 ~ "Right",
lrscale %in% c(77, 88, 99) ~ NA_character_
))
france_data <- france_data %>% filter(!is.na(ccrdprs))
france_data <- france_data %>% filter(!is.na(lrscale))
table(france_data$ccrdprs)
##
## 0 1 2 3 4 5 6 7 8 9 10
## 25 8 23 34 52 185 164 312 423 145 260
table(france_data$lrscale)
##
## Left Right
## 477 1154
test_stat <- france_data %>%
specify(explanatory = lrscale,
response = ccrdprs) %>%
hypothesize(null = "independence") %>%
calculate(stat = "t", order = c("Left", "Right"
))
print(test_stat$stat)
## t
## 4.350531
#interpreation:
null_distribution <- france_data %>%
specify(explanatory = lrscale,
response = ccrdprs) %>%
hypothesize(null = "independence") %>%
generate(reps = 1000, type = "permute") %>%
calculate(stat = "t")
## Warning: The statistic is based on a difference or ratio; by default, for
## difference-based statistics, the explanatory variable is subtracted in the
## order "Left" - "Right", or divided in the order "Left" / "Right" for
## ratio-based statistics. To specify this order yourself, supply `order =
## c("Left", "Right")` to the calculate() function.
p_val <- null_distribution %>%
get_pvalue(obs_stat = test_stat, direction = "two-sided")
## Warning: Please be cautious in reporting a p-value of 0. This result is an approximation
## based on the number of `reps` chosen in the `generate()` step.
## ℹ See `get_p_value()` (`?infer::get_p_value()`) for more information.
p_val
## # A tibble: 1 × 1
## p_value
## <dbl>
## 1 0
#Task 5 #Now do Step 4 (i.e., the null distribution visualization with confidence intervals) for the same variables and country as Task 4, and interpret the output.
null_distribution %>%
visualize() +
shade_p_value(obs_stat = test_stat, direction = "two-sided")
null_distribution
## Response: ccrdprs (numeric)
## Explanatory: lrscale (factor)
## Null Hypothesis: independence
## # A tibble: 1,000 × 2
## replicate stat
## <int> <dbl>
## 1 1 0.772
## 2 2 -0.322
## 3 3 0.478
## 4 4 -0.313
## 5 5 1.63
## 6 6 -2.28
## 7 7 0.648
## 8 8 0.172
## 9 9 -1.98
## 10 10 0.889
## # ℹ 990 more rows
conf_int <- null_distribution %>%
get_confidence_interval(level = 0.95, type = "percentile")
null_distribution %>%
visualize() +
shade_p_value(obs_stat = test_stat, direction = "two-sided") +
shade_confidence_interval(endpoints = conf_int)
null_distribution
## Response: ccrdprs (numeric)
## Explanatory: lrscale (factor)
## Null Hypothesis: independence
## # A tibble: 1,000 × 2
## replicate stat
## <int> <dbl>
## 1 1 0.772
## 2 2 -0.322
## 3 3 0.478
## 4 4 -0.313
## 5 5 1.63
## 6 6 -2.28
## 7 7 0.648
## 8 8 0.172
## 9 9 -1.98
## 10 10 0.889
## # ℹ 990 more rows