# 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.    Which of the following best describes a confounding variable?

1. A variable that is manipulated by the experimenter.
2. A variable that has been measured using an unreliable scale.
3. A variable that affects the outcome being measured as well as, or instead of, the independent variable.
4. A variable that is made up only of categories.

The correct answer is c) A variable that affects the outcome being measured as well as, or instead of, the independent variable. This is correct because a confounding variable is an unforeseen and unaccounted-for variable that jeopardizes reliability and validity of an experiment's outcome.

2.    A variable that measures the effect that manipulating another variable has is known as:

1. A dependent variable
2. A confounding variable
3. A predictor variable
4. An independent variable

The correct answer a) A dependent variable. This is because a dependent variable (or outcome variable) is a variable that is thought to be affected by changes in an independent variable.

3.    A predictor variable is another name for:

1. A dependent variable
2. An independent variable
3. A confounding variable
4. A discrete variable

The correct answer is b) An independent variable. An independent variable (or predictor variable) is a variable that is thought to be the cause of some effect. This term is usually used in experimental research to denote a variable that the experimenter has manipulated.

4.    The discrepancy between the numbers used to represent something that we are trying to measure
and the actual value of what we are measuring is called:

1. Variance
2. The ‘fit’ of the model
3. Reliability
4. Measurement error

The correct answer is d) Measurement error. This is because, it’s one thing to measure variables, but it’s another thing to measure them accurately.

5.    What kind of variable is IQ, measured by a standard IQ test?

1. Categorical
2. Continuous
3. Discrete
4. Nominal

The correct answer is b) Continuous. A continuous variable is one for which, within the limits the variable ranges, any value is possible