Probability and Statistics: Exercises
6. Independence. The function rnorm(n,mean,sd) generates n draws from
a normal distribution. Generate 1000 observations from a normal distribution with mean 0 and standard
deviation 1 twice. Using cor(), compute the correlation between the two sets of draws. After that,
construct a scatterplot with the two sets of draws.
# Draw 1000 observations from a normal distribution.
draws_1 <- ___(___, ___, 1)
# Draw 1000 observations from a normal distribution.
draws_2 <- ___
# Compute correlation.
correlation <- ___(draws_1, draws_2)
# Create scatterplot of draws_1 and draws_2.
plot(draws_1, ___)
# Draw 1000 observations from a normal distribution.
draws_1 <- rnorm(1000, 0, 1)
# Draw 1000 observations from a normal distribution.
draws_2 <- rnorm(1000, 0, 1)
# Compute correlation.
correlation <- cor(draws_1, draws_2)
# Create scatterplot of draws_1 and draws_2.
plot(draws_1, draws_2)
test_error()
test_object("draws_1", incorrect_msg="Did you enter the correct arguments to `rnorm()`?")
test_object("draws_2", incorrect_msg="Did you enter the correct arguments to `rnorm()`?")
test_object("correlation", incorrect_msg="Did you enter the correct arguments to `cor()`?")
success_msg("Good job! Based on your findings, do the draws appear to be independent?")
Did you use the
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