Table of Contents

- What is the definitional formula in statistics?
- Under what circumstances is the definitional formula easy to use?
- In which circumstance is the computational formula preferred over the definitional formula when computing ss the sum of the squared deviations for a population quizlet?
- How do you find the variance of a sum of squares?

## What is the definitional formula in statistics?

the formal verbal definition of a statistical concept. For example, the definitional formula of variance states that it is the mean squared difference between a score and the mean of all of the scores.

**What is the definitional formula for standard deviation?**

The computational formula for the standard deviation of a sample using raw data is: The formula reads: capital S (standard deviation of a sample) equals the square root of the sum of all the raw scores squared minus the sum of all the raw scores then squared and divided by the sample size.

**What is a conceptual formula?**

the equation used to calculate values for a statistical concept. This contrasts with the definitional formula, which is the formal verbal definition of the concept.

### Under what circumstances is the definitional formula easy to use?

The definitional formula is easy to use when the mean is a whole number and there are relatively few scores.

**How do you calculate variance and standard deviation?**

To calculate the variance, you first subtract the mean from each number and then square the results to find the squared differences. You then find the average of those squared differences. The result is the variance. The standard deviation is a measure of how spread out the numbers in a distribution are.

**How do you find variance without data set?**

Follow these steps: Work out the mean (the simple average of the numbers.) Then, for each number, subtract the mean and square the result (the squared difference). Finally, work out the average of those squared differences.

#### In which circumstance is the computational formula preferred over the definitional formula when computing ss the sum of the squared deviations for a population quizlet?

The computational formula is preferred when the mean is not a whole number or when there are many scores. (Note: The definitional formula for SS works well with these scores.)

**Under what circumstances does the computational formula have an advantage over the definitional formula when computing ss the sum of the squared deviations?**

The computational formula is better when the mean is a fraction or decimal value and usually easier with a large number of scores.

**How is deviation calculated?**

Steps for calculating the standard deviation

- Step 1: Find the mean.
- Step 2: Find each score’s deviation from the mean.
- Step 3: Square each deviation from the mean.
- Step 4: Find the sum of squares.
- Step 5: Find the variance.
- Step 6: Find the square root of the variance.

## How do you find the variance of a sum of squares?

The variance (σ2), is defined as the sum of the squared distances of each term in the distribution from the mean (μ), divided by the number of terms in the distribution (N). You take the sum of the squares of the terms in the distribution, and divide by the number of terms in the distribution (N).