Statistics Chapter 2

What types of charts would be used to summarize tables for one variable of qualitative data?

bar chart, pie chart, and parento chart

What are the characteristics of a frequency distribution?

used for qualitative data, groups data into categories, and records number of observations into each category Ex: groups weather conditions throughout the week

What relative frequency?

Ex: weather conditions throughout out the months. One day cloudy divided by 31 days of month equal relative frequency. frequency/number of total days= relative frequency. Relative frequency must appear in percentage that equal to 100

is tha segment circle whose segments portray the relative frequencies of the categories of some qualitative variables.

pie chart

depicts the frequency or the relative frequency for each category of the qualitative data as a bar rising vertically from the horizontal axis.

bar chart

What are the types of charts that formed an ordered array of numerical data?

stem-and-leaf display

What are the types of charts that formed a frequency distribution and cumulative distribution of numerical data?

histogram, polygon, and ogive

groups data into intervals called classes, and records the number of observations that fall into each class. Classes are contradictory and comprehensive.

frequency distribution

What do the number of classes usually range from?

5 to 20

specifies how many observations fall below the upper limit of a particular class. Determines the amount of frequency as a certain a certain in the frequency distribution chart

cumulative frequency distribution

identifies the proportion or fraction of values that fall into each class. frequency/total number of frequency

relative frequency distribution

gives the proportion or fraction of values that fall below the upper limit of each class. refer back to cumulative frequency distribution

cumulative relative frequency distribution

is a visual representation of a frequency or a relative frequency distribution

histogram, polygon

What does bar height represent in the histrogram

the respective class frequency (or relative frequency)

What does the bar width represent in the histogram?

class width

mirror image on both sides of its center

symmetric

data forma long, narrow tail to the right

positively skewed

data forms a long, narrow tail to the left

negatively skewed

Where is the associated frequency and relative frequency located on a polygon chart?

y-axis

Where are the class midpoints located on a polygon chart?

x-axis

is a visual representation of a cumulative frequency or a cumulative relative frequency distrubition

ogive

Where do you plot the cumulative frequency (or cumulative relative frequency) of each class on a ogive chart?

above the upper limit of the corresponding class and then the neighboring points are then connected

provides a visual display of quantitative data and gives an overall picture of the data's center and variability

stem-and-leaf diagram

What does the stem of the stem-and-leaf diagram consist of?

leftmost digits

What does the leaf of the stem-and-leaf diagram consist of?

the last digits

Give an example of how numerical values are separated in stem-and-leaf diagrams?

Age=36: Stem=3 Leaf=6

is used to determine if two variables are related

scatterplot

What are linear relationship in scatterplots

the upward or downward sloping trend of the data

What is positive linear relationship?

as the x-axis increases, the y-axis increases

What is negative linear relationship?

as the x-axis increases, the y-axis decreases

Explain curvilinear relationship in scatterplots

As x increases, y increases at an increasing (or decreasing) rate. As x increases, y decreases at an increasing (or decreasing) rate.

What is no relationship scatterplots?

data that is randomly scattered with no discernible pattern

What does the histogram have the ability to do in terms of graphing?

cannot flip axis, can use relative frequency, frequency, % frequency, midpoints and boundaries

What can a % polygon use in terms of graphing?

must use midpoint and frequency or percent frequency

What can a cumulative percent graph or an ogive use?

uses lower or upper class boundaries

Which central tendency are resistant measures?

mode and median

total spread in set, sensitive to outliers

range

average of squared deviation of values from the mean

variance

shows variation of mean, square root of variance, majority of observations lie with in +1 or -1 standard deviations

standard deviation

number of standard deviations a data value is from the mean

z-score

mean<median

left skewed

mean=median

symmetrical

mean>median

right skewed

What is the empirical rule within 1 standard deviation of the mean

68%

What is the empirical rule within 2 standard deviation of the mean?

95%

What is the empirical rule within 3 standard deviations of the mean?

99.7%

What is the first rule of calculating quartile measures?

if the result is a whole number then it is the ranked position to use

What is the second rule of calculating quartile measure?

if the result is a fractional half (2.5, etc) then average the two corresponding data values

What is the third rule of calculating quartile measure?

if the result is neither (not a whole number or a fractional number) then round the results to the nearest integer to find the ranked position