click below
click below
Normal Size Small Size show me how
Chapter 2
Term | Definition |
---|---|
Class | A quantitative or qualitative category that raw data is placed into |
Frequency | The number of data values that are contained in a particular class |
Frequency distribution | The organization of raw data in table form, using classes and frequency |
Class width | Distance between consecutive lower limits and consecutive upper limits found by subtracting the lower or upper limit from the one above |
Class limits | The span of values that can be counted in a particular class |
Class boundaries | Numbers used to separate the class so there are no gaps in the frequency distribution |
Midpoint formula | Xm=lower limit+upper limit/2 |
Categorical | Used for data that can be put into specific categories (nominal or ordinal) |
Grouped | Used when the range of data is larger (>10) |
Ungrouped | Used when the range of data values is relatively small |
List the three things that can make a graph misleading | 1. 3-D or 2-D pictures 2. Labeling the y-axis to make a point or not 3. Omitting labels or units on the axis of a graph |
List the rules to follow for class width | 1. 5-20 classes 2. Preferable that class width be an odd number 3. Classes must be mutually exclusive 4. Classes must be continuous 5. Classes must be exhaustive 6. Classes must be equal width |
List the reason for constructing a frequency distribution | 1.Organize data in meaningful, intelligible way 2.Enable the reader to determine shape of distribution 3.Help with computations like the measures of average 4.Enable the readers to draw charts and graphs 5.Enable readers to compare different data sets |
What is the purpose of graphs? | To convey the data to the viewers in a graphical form |
List the uses of graphs | 1. To describe and analyze the data 2. To get the audience's attention 3. To discuss an issue 4. To reinforce a critical point 5. To summarize a data set 6. To discover a trend or pattern |
List the three most commonly used graphs | 1. Histogram 2. Frequency polygon 3. Ogive |
What does the relative frequency represent in a graph? | Represent distributions that use proportions instead of raw data as frequencies |
How do you find the relative frequency? | You divide the frequency by the total number |