Ms. Walker wants to describe the average score on your first psychology test. Which measure of central tendency is she most likely to use?

• mean

• median

• mode

• harmonic mean

Mrs. Baumann gives an exam where most of the students receive failing grades and only a few students receive high scores. When the exam scores are plotted, the distribution will be

• positively skewed

• negatively skewed

• symmetrical

• impossible to predict without more information

In a strongly skewed distribution, the best indicator of central tendency is usually the

• mean
• median
• mode
• standard deviation

The standard deviation

• indicates the average difference between each score in a group and the mean for that group of scores

• reveals the degree of skew for a group of scores

• is sensitive to scores at the extremes of a distribution of scores

• is used to determine whether a data set is positively or negatively skewed

If Andy has an IQ of 130. If the mean for IQ is 100 with a standard deviation of 15, what percentage of the population has an IQ greater than Andy's, assuming the population falls on a normal distribution?

• 0 percent

• 2.5 percent

• 32 percent

• 50 percent

A study is said to have _______________ if it yields consistent results each time it is repeated.

• validity

• reliability

• sample

• correlation

Factors that cause differences between the experimental group and control group other than the independent variable are _____________________.

• control group

• dependent variables

• confounding variables

• experimental group

The factor the researcher manipulates in a controlled experiment is the _________________.

• dependent variable

• independent variable

• confounding variable

• participant bias

The subgroup of the population that participates in the study is referred to as the _________.

• sample

• assignment

• group

• population

When a researcher's expectations or preferences about the outcome of a study influence the results, ____________ bias has occurred.

• social desirability

• self-serving

• experimenter

• hindsight