MMW-2F

• How are large set of data often displayed

  Grouped frequency distribution or histogram
• Grouped Frequency Distribution


  It shows how often (frequently) certain events occurred.
• Class 


  The interval in a grouped frequency distribution.
• Any data value that lies on a common boundary is assigned to the higher class.
• Histogram


  Graph of a frequency distribution.
• Histogram


  Provides a pictorial view of how the data are distributed
• Relative Frequency Distribution


  Type of frequency distribution that lists the percent of data in each class.
• Relative Frequency Histogram 


  It is drawn by using the data in the relative frequency distribution.
• One advantage of using a relative frequency distribution instead of a grouped frequency distribution is that there is a direct correspondence between the percent values of the relative frequency distribution and probabilities.
• Normal Distribution


  forms a bell shaped curve that is symmetric about a vertical line throgh the mean of the data.
• Empirical Rule


  Describes the percent of data that lie within 1, 2, 3 standard deviations of the mean in a normal distribution.
• Standard Normal Distribution


  The normal distribution of z-scores.
• Standard Normal Distribution


  The normal distribution that has mean of 0 and standard deviation of 1.
• Tail Region


  A region of the standard normal distribution to the right.
• Cut-off Score


  A score that separates data into two groups such that the data in one group satisfy a certain requirement and the data in the other group.
• Bavariate Data


  Data involving two variables
• Least-Squares Regression Line 


  The line that minimizes the sum of the squares of the vertical deviations from each data point to the line.
• Interpolation


  The procedure that made use of an equation to determine a point between given data points.
• Extrapolation


  The process of using an equation to determine a point to the right or left of given data points.
• Linear Correlation Coefficient


  Determine the strength of a linear relationship between two variables.
• Descriptive Statistics 


  Involves the collection, organization, summarization, and presentation of data.
• Inferential Statistics 


  Interprets and draw conclusions from the data.
• Statistics


  Involves the collection, organization, summarization, presentation, and interpretation of data.
• Three types of averages

  • arithmetic mean
  • median
  • mode
• Mean/Arithmetic mean


  The sum of the numbers divided by n.
• Population


  Situations the entire group under consideration.
• Sample


  Any subset of a population.
• Median


  The middle number or mean of the two middle numbers
• Ranked List


  Any list of numbers that is arranged in numerical order from smallest to largest or largest to smallest.
• Mode


  A list of numbers in which a number occurs most frequently.
• The mean, median, and mode are generally not equal.
• A change in any of the numbers changes the mean, and the mean can be changed drastically by changing an extreme value.
• The median and mode are usually not changed by changing an extreme value.
• Weighted Mean


  The sum of the products formed by multiplying each number by its assigned weight and divided by the sum of all weights.
• Raw Data


  Data that have not been organized or manipulated in any manner.
• Frequency Distribution


  List observed events and the frequency of occurrence of each observed event.
• Linear Interpolation


  A method used to find a particular number between two given numbers.
• Range


  The difference between the greatest data value and the least data value.
• Standard Deviation


  A measure of dispersion that is less sensitive to extreme values.
• Variance


  The square of standard deviation.