Importing the data

knitr::opts_chunk$set(error = TRUE)
a3 <-  read.csv("/Users/dhruvsapra/Downloads/assign.csv")  

# if you use any packages, you can library() them here (but none are needed)

Question 1

Null hypothesis in sentence form:

The mean daily screentime for school-age children in non-North American countries post-pandemic is 4.4 hours. This hypothesis posits that the average screentime has not increased from the pre-established average prior to the pandemic.

Null hypothesis in symbolic form:

cat(“H0: μ = 4.4”)

Alternative hypothesis in symbolic form:

cat(“H1: μ > 4.4”)

Question 2

Use this space for your answer to Question 2.

The validity of the t-test for our hypothesis relies on meeting the following model conditions:

1. Independence

Each child’s screentime data point is collected independently. This condition is generally met if each observation represents a different individual and the data collection process does not link the observations.

2. Normality

The screentime data should be normally distributed, especially for smaller samples. This can be assessed through QQ-plots or the Shapiro-Wilk test. For large samples (n > 30), the Central Limit Theorem helps mitigate non-normality concerns.

3. Random Sampling

The data should come from a random sample of the population, ensuring it’s representative of all school-age children in non-North American countries.

4. Sample Size

Adequate sample size: Generally, a sample size of 30 or more is recommended to ensure that the sampling distribution of the mean is approximately normal.

If you need R code/output as part of your answer, you could use the following R chunk or create additional ones

shapiro.test(assign$screen)
## Error in assign$screen: object of type 'closure' is not subsettable

Question 3

# conduct test
t_test_result <- t.test(assign$screen, mu = 4.4, alternative = "greater")
## Error in assign$screen: object of type 'closure' is not subsettable
# Display the t-test results
print(t_test_result)
## Error in eval(expr, envir, enclos): object 't_test_result' not found