Research Methods: Central Tendency Review

What does the mean represent in measures of central tendency?

• The most frequent number

• The middle number

• The mathematical average of all numbers

• The measure of how much scores vary around the mean score

Which measure of variation describes the gap from the highest to the lowest number?

• Mode

• Median

• Range

• Mean

What value indicates a perfect positive correlation?

• -1.00

• 0.00

• +1.00

• ≤ 0.05

What is the significance of a P Score ≤ 0.05 in statistical analysis?

• Indicates a 95% or more chance due to random factors

• Indicates a 5% or less chance due to random factors

• No correlation

• Perfect negative correlation

Which type of research method involves manipulating one or more factors to observe the effect?

• Correlational

• Descriptive

• Experimental

• Standard Deviation

What does a Z-score represent?

• A measure of how much scores vary around the mean score

• The standard deviation from the mean

• The total sum of all scores

• The correlation between two variables

What percentage of data falls within one standard deviation from the mean in a standard normal distribution?

• A) 68.2%

• B) 95.4%

• C) 99.7%

• D) 50%

How much data falls within two standard deviations below the mean in a standard normal distribution?

• A) 2.1%

• B) 13.6%

• C) 34.1%

• D) 47.5%

What is the total percentage of data that falls within three standard deviations from the mean in a standard normal distribution?

• A) 68.2%

• B) 95.4%

• C) 99.7%

• D) 99.9%

What is the median?

• 62
• 58
• 66
• 60