# Multiple choice questions

Quizzes are available to test your understanding of the key concepts covered in each chapter. Click on the quiz below to get started.

1.    A frequency distribution in which there are too many scores at the extremes of the distribution
said to be:

1. Positively skewed
2. Leptokurtic
3. Platykurtic
4. Negatively skewed

The correct answer is c) Platykurtic. This is because a platykurtic distribution describes a distribution with negative kurtosis and it is relatively thin in the tails (has light tails) and tends to be flatter than normal.

2.    A frequency distribution in which there are too few scores at the extremes of the distribution
said to be:

1. Leptokurtic
2. Positively skewed
3. Negatively skewed
4. Platykurtic

The correct answer is a) Leptokurtic. This is because a leptokurtic distribution describes a distribution with positive kurtosis, it has many scores in the tails (a so-called heavy-tailed distribution) and is pointy.

3.    Which of the following is designed to compensate for practice effects?

1. A repeated measured design
2. Counterbalancing
3. Giving participants a break between tasks
4. A control condition

The correct answer is b) Counterbalancing. This is because although practice effects are impossible to eliminate completely, we can ensure that they produce no systematic variation between our conditions by counterbalancing the order in which a person participates in a condition.

4.    Variation due to variables that have not been measured is known as:

1. Homogenous variance
2. Systematic variation
3. Residual variance
4. Unsystematic variation

The correct answer is d) Unsystematic variation. This is because unsystematic variation results from random factors that exist between the experimental conditions (such as natural differences in ability, the time of day, etc.)

5.    In IBM SPSS, what does clicking on this icon do?

1. Split the file by a coding variable.
2. Display or hide the value labels of coding variables.
3. Take you to a particular case.
4. Tell you which data analysis to perform on your data.

The correct answer is b) Display or hide the value labels of coding variables. This is correct because we often group people together and use a coding variable to let the computer know that a certain participant belongs to a certain group.