Questions: Consider the following data:
9, -5, 9, -5, 2, 9, -5
Step 2 of 3: Calculate the value of the sample standard deviation. Round your answer to one decimal place.
Transcript text: Consider the following data:
\[
9,-5,9,-5,2,9,-5
\]
Step 2 of 3: Calculate the value of the sample standard deviation. Round your answer to one decimal place.
AnswerHow to enter your answer (opens in new window) 2 Points
Solution
Solution Steps
Step 1: Calculate the sample mean
The sample mean (\(\bar{x}\)) is calculated as \(\bar{x} = \frac{1}{7}\sum_{i=1}^{7}x_i\), which equals 2.
Step 2: Calculate the squared differences from the mean
For each observation \(x_i\) in the dataset, calculate the squared difference from the mean \((x_i - \bar{x})^2\).
The squared differences are: [49, 49, 49, 49, 0, 49, 49].
Step 3: Sum up all the squared differences
The total squared deviation from the mean is \(\sum_{i=1}^{7}(x_i - \bar{x})^2\), which equals 294.
Step 4: Divide the total squared deviation by \(n-1\)
This gives us the variance: \(\frac{1}{6}\sum_{i=1}^{7}(x_i - \bar{x})^2\), which equals 49.
Step 5: Take the square root of the variance
This gives us the sample standard deviation: \(\sqrt{\frac{1}{6}\sum_{i=1}^{7}(x_i - \bar{x})^2}\), which equals 7.
Final Answer:
The sample standard deviation of the dataset, rounded to 1 decimal place(s), is 7.