Part D Stats Practice

A researcher finds that the average score on a memory test is 72 out of 100 for a group of 50 participants. What statistical measure is this describing?

• Mode

• Mean

• Range

• Standard Deviation

In a distribution of test scores, 75% of the scores fall below a score of 85. Which statistical principle is this an example of?

• Mode

• Percentile Rank

• Range

• Skewness

In a data set of reaction times, the most frequent reaction time recorded is 2.5 seconds. What statistical measure is being described?

• Mean

• Mode

• Range

• Standard Deviation

A researcher notes that the difference between the highest and lowest scores on a creativity test is 42 points. What statistical concept is being referenced here?

• Standard Deviation

• Mode

• Range

• Correlation Coefficients

In a study comparing two groups, one group received a new medication, and the other received a placebo. The difference between the groups is unlikely due to chance, as p < 0.05. Which statistical principle does this represent?

• Correlation Coefficient

• Statistical Significance

• Standard Deviation

• Effect Size

A scatterplot of participants’ hours of sleep and test performance shows a correlation coefficient of +0.75. What is being measured here?

• Correlation Coefficient

• Statistical Significance

• Standard Deviation

• Effect Size

In a distribution of exam scores, most of the scores are clustered around the low end, with a few scores much higher than the rest. What type of skewness is this?

• Positive Skew

• Negative Skew

• Standard Deviation

• Mode

After analyzing data from a memory experiment, the researcher reports a small effect size, indicating that the independent variable had only a slight impact on participants' performance. What statistical measure is this?

• Range

• Percentile Rank

• Effect Size

• Statistical Significance

In a normal distribution of IQ scores, the average score is 100, and 68% of the scores fall within 15 points of the average. What statistical measure is being used to describe the spread of the scores?

• Mean

• Mode

• Range

• Standard Deviation

In a study examining reaction times, a participant's score ranks in the 90th percentile. What does this mean?

• The participant’s score is below the mean.

• The participant’s score is equal to the mode.

• The participant’s score is higher than 90% of the other scores.

• The participant’s score is within one standard deviation of the mean.