## Multiple choice questions

**Take the quiz test your understanding of the key concepts covered in the chapter. Try testing yourself before you read the chapter to see where your strengths and weaknesses are, then test yourself again once you’ve read the chapter to see how well you’ve understood.**

**The degree to which a statistical model represents the data collected is known as the:**

__Answer choices__

- Fit
- Homogeneity
- Reliability
- Validity

#### Answer: Fit

**If we calculated an effect size and found it was r = .42 which expression would best describe the size of effect?**

__Answer choices__

- Small
- Small to medium
- Medium to large
- Large

**What is the relationship between the sum of squared errors (SS), the sample size (n) and the variance (s2)? **

__Answer choices__

- SS = s2/(n – 1).
- s2 = SS(n – 1).
- n = (s2/SS) – 1.
- s2 = SS/(n – 1).

#### Answer: s2 = SS/(n – 1)

**If we use the mean as a model, what does the variance represent?**

__Answer choices__

- The average error between the model and the observed data.
- The total error between the model and the observed data.
- The squared total error between the model and the observed data.
- The square-rooted average error between the model and the observed data.

#### Answer: The average error between the model and the observed data

**Given a test is normally distributed with a mean of 30 and a standard deviation of 6:**

**What is the probability that a single score drawn at random will be greater than 34?**
**What is the probability that a sample of 9 scores will have a mean greater than 34?**
**What is the probability that the mean of a sample of 16 scores will be either less than 28 or greater than 32?**

__Answer choices__

- 0.0228
- 0.2524
- 0.1826

#### Answer: 0.2524