Understanding T-Tests

What is the primary purpose of a one-sample t-test?

• To compare the means of two dependent groups

• To compare the means of two independent groups

• To compare the mean of a sample with a known reference mean

• To test the variance of a single sample

In the example of the chocolate bar manufacturer, what is the claimed average weight of the bars?

• 48 grams

• 50 grams

• 52 grams

• 45 grams

When should you use an independent samples t-test?

• When testing the variance of a single sample

• When comparing the mean of a sample with a reference mean

• When comparing the means of two independent groups

• When comparing the means of two dependent groups

In the painkiller effectiveness example, how many people were divided into two groups?

• 40 people

• 30 people

• 50 people

• 60 people

What is a key characteristic of a paired samples t-test?

• It compares the means of two independent groups

• It tests the variance of a single sample

• It compares the means of two dependent groups

• It compares the mean of a sample with a reference mean

What must be true about the variable for a t-test to be valid?

• It must be an ordinal variable

• It must be a categorical variable

• It must be a nominal variable

• It must be a metric variable

What is the null hypothesis in a one-sample t-test?

• The sample mean is less than the given reference value

• The sample mean is not equal to the given reference value

• The sample mean is equal to the given reference value

• The sample mean is greater than the given reference value

What two values are needed to calculate the T value in a t-test?

• The mean and median

• The difference between the means and the standard deviation

• The range and the interquartile range

• The variance and the standard deviation

How does a larger dispersion of the mean affect the T value?

• It makes the T value larger

• It makes the T value smaller

• It has no effect on the T value

• It doubles the T value

What happens to the T value if the difference between the means is greater?

• The T value becomes negative

• The T value becomes larger

• The T value remains the same

• The T value becomes smaller