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segmentCKCode
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ckcode-chapter-b5-quantitative-explanatory
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ckcode ⌲ chapter-b5-quantitative-explanatory
library(coursekata)
# edit the Height2Group_model code to create Height_model
Height2Group_model <- lm(Thumb ~ Height2Group, data = Fingers)
# save the predictions of the Height_model as a new variable in Fingers
Fingers$Height_predict <-
# this code prints out the first 6 observations
head(select(Fingers, Thumb, Height, Height_predict))
# edit the Height2Group_model code to create Height_model
Height_model <- lm(Thumb ~ Height, data = Fingers)
# save the predictions of the Height_model as a new variable in Fingers
Fingers$Height_predict <- predict(Height_model)
# this code prints out the first 6 observations for 3 columns
head(select(Fingers, Thumb, Height, Height_predict))
ex() %>% {
check_object(., "Height_model") %>%
check_equal()
check_object(., "Fingers") %>%
check_column("Height_predict") %>%
check_equal()
}
CK Code: B5_Code_Quantitative_01
library(coursekata)
# saves the Height model
Height_model <- lm(Thumb ~ Height, data = Fingers)
# print it out
# saves the Height model
Height_model <- lm(Thumb ~ Height, data = Fingers)
# print it out
Height_model
ex() %>% check_output_expr("Height_model")
CK Code: B5_Code_Regression_01
require(coursekata)
Fingers$SexNum <- as.numeric(Fingers$Sex)
# fit a model of Thumb length based on Sex
Sex_model <- lm()
# fit a model of Thumb length based on SexNum
SexNum_model <- lm()
# this prints the parameter estimates from the two models
Sex_model
SexNum_model
# fit a model of Thumb length based on Sex
Sex_model <- lm(Thumb ~ Sex, data=Fingers)
# fit a model of Thumb length based on SexNum
SexNum_model <- lm(Thumb ~ SexNum, data=Fingers)
# this prints the parameter estimates from the two models
Sex_model
SexNum_model
ex() %>% {
check_object(., "Sex_model") %>% check_equal()
check_object(., "SexNum_model") %>% check_equal()
check_output_expr(., "Sex_model
SexNum_model")
}
CK Code: B5_Code_Comparing_01
require(coursekata)
# this calculates SST
empty_model <- lm(Thumb ~ NULL, data=Fingers)
print("SST")
sum(resid(empty_model)^2)
# this calculates SSE
Height_model <- lm(Thumb ~ Height, data = Fingers)
print("SSE")
sum(resid(Height_model)^2)
# no test
ex() %>% check_error()
CK Code: B5_Code_Error_01
require(coursekata)
# this saves the Height_model
Height_model <- lm(Thumb ~ Height, data = Fingers)
# print the ANOVA tables for this model
# this saves the Height_model
Height_model <- lm(Thumb ~ Height, data = Fingers)
# print the ANOVA tables for this model
supernova(Height_model)
ex() %>%
check_function("supernova") %>%
check_result() %>%
check_equal()
CK Code: B5_Code_Assessing_01
require(coursekata)
Fingers <- filter(Fingers, Thumb >= 33 & Thumb <= 100)
# this transforms all Thumb lengths into z-scores
Fingers$zThumb <- zscore(Fingers$Thumb)
# modify this to do the same for Height
Fingers$zHeight <-
# this transforms all Thumb lengths into z-scores
Fingers$zThumb <- zscore(Fingers$Thumb)
# modify this to do the same for Height
Fingers$zHeight <- zscore(Fingers$Height)
ex() %>% check_object("Fingers") %>% {
check_column(., "zThumb") %>% check_equal()
check_column(., "zHeight") %>% check_equal()
}
CK Code: B5_Code_Correlation_01
require(coursekata)
Fingers <- Fingers %>%
filter(Thumb >= 33 & Thumb <= 100) %>%
mutate(
zThumb = zscore(Thumb),
zHeight = zscore(Height)
)
# this makes a scatterplot of the raw scores
# size makes the points bigger or smaller
gf_point(Thumb ~ Height, data = Fingers, size = 4)
# zThumb and zHeight have already been created for you
# modify the code below to make a scatterplot of the z-scores
gf_point( , data = Fingers, size = 4, color = "navy")
# this makes a scatterplot of the raw scores
# size makes the points bigger or smaller
gf_point(Thumb ~ Height, data = Fingers, size = 4)
# zThumb and zHeight have already been created for you
# modify the code below to make a scatterplot of the z-scores
gf_point(zThumb ~ zHeight, data = Fingers, size = 4, color = "navy")
ex() %>% {
check_function(., "gf_point", index = 1) %>% {
check_arg(., "object") %>% check_equal()
check_arg(., "data") %>% check_equal()
}
check_function(., "gf_point", index = 2) %>% {
check_arg(., "object") %>% check_equal()
check_arg(., "data") %>% check_equal()
}
}
CK Code: B5_Code_Correlation_02
require(coursekata)
Fingers <- Fingers %>%
filter(Thumb >= 33 & Thumb <= 100) %>%
mutate(
zThumb = zscore(Thumb),
zHeight = zscore(Height)
)
Height_model <- lm(Thumb ~ Height, data = Fingers)
# this fits a regression model of Thumb by Height
lm(Thumb ~ Height, data = Fingers)
# write code to fit a regression model predicting zThumb with zHeight
# this fits a regression model of Thumb by Height
lm(Thumb ~ Height, data = Fingers)
# write code to fit a regression model predicting zThumb with zHeight
lm(zThumb ~ zHeight, data = Fingers)
ex() %>%
check_function("lm", index = 2) %>%
check_result() %>%
check_equal()
CK Code: B5_Code_Correlation_03
require(coursekata)
Fingers <- Fingers %>%
filter(Thumb >= 33 & Thumb <= 100) %>%
mutate(
zThumb = zscore(Thumb),
zHeight = zscore(Height)
)
# this calculates the correlation of Thumb and Height
cor(Thumb ~ Height, data = Fingers)
cor(Thumb ~ Height, data = Fingers)
ex() %>% check_function("cor") %>% check_result() %>% check_equal()
CK Code: B5_Code_Correlation_04
require(coursekata)
Fingers <- Fingers %>%
filter(Thumb >= 33 & Thumb <= 100) %>%
mutate(
zThumb = zscore(Thumb),
zHeight = zscore(Height)
)
Hand <- select(Fingers, Thumb, Index, Middle, Ring, Pinkie, Height)
# run the cor() function with the Hand data frame
cor(Hand)
ex() %>% check_function("cor") %>% check_result() %>% check_equal()
CK Code: B5_Code_Pearsonsr_01
require(coursekata)
Fingers <- Fingers %>%
filter(Thumb >= 33 & Thumb <= 100) %>%
mutate(
zThumb = zscore(Thumb),
zHeight = zscore(Height)
)
# this code finds the square root of the PRE.1529
sqrt(.1529)
# add code to calculate the correlation between Thumb and Height
# this code finds the square root of .1529
sqrt(.1529)
# add code to calculate the correlation between Thumb and Height
cor(Thumb ~ Height, data = Fingers)
ex() %>% check_output_expr("cor(Thumb ~ Height, data = Fingers)")
CK Code: B5_Code_Pearsonsr_02
require(coursekata)
Fingers$ShuffThumb <- shuffle(Fingers$Thumb)
shuffled_b1 <- b1(ShuffThumb ~ Height, data = Fingers)
gf_point(ShuffThumb ~ Height, data = Fingers) %>%
gf_lm(color = "purple") %>%
gf_labs(title = paste("Shuffled Data / b1 = ", round(shuffled_b1, digits = 2)))
# no solution; just submit the code from the prompt
ex() %>% check_error()
CK Code: B5_Code_Fitting_01
require(coursekata)
set.seed(42)
# use do() to create 10 shuffled b1s
# use do() to create 10 shuffled b1s
do(10) * b1(shuffle(Thumb) ~ Height, data = Fingers)
ex() %>% {
check_function(., 'do') %>%
check_arg('object') %>% check_equal()
check_function(., 'b1') %>% {
check_arg(., 'object') %>% check_equal(eval = FALSE)
check_arg(., 'data') %>% check_equal()
}
}
CK Code: B5_Code_Fitting_02
require(coursekata)
# run your code here
CK Code: B4_Code_Review2_01