Descriptive Statistics

• Measures of central tendency include mean, median, and mode
• The Mode is the most frequently occuring number in a data set
• The Median is the middle score when the data is in numerical order
• The Mean is the sum of all number divided by how many numbers there are
• Measures of Dispersion include range and standard deviation
• The Range is the difference between the highest and lowest values
• Standard Deviation shows to what extent the values deviate from the mean
• A low standard deviation indicates consistency in the data set
• Bar Charts are used when data is in categories (discrete data)
• Histograms are used to present continuous data on interval or ratio scales of measurement
• Scattergrams are used for correlational analysis
• Distrubutions show the spread of data
• In Normal Distribution the central tendencies occupy the same midpoint
• Positively skewed distribution is when most of the distribution is concentrated to the left