MATH 9C midterm reviewer

Data

Facts, especially numerical facts, collected together for reference or information

Information

Knowledge communicated concerning some particular fact.

Statistics

is a tool for creating new understanding from data.

Descriptive statistics

are methods of organizing, summarizing, and presenting data in a convenient and informative way.

graphical summaries and numerical techniques

methods under Descriptive statistics

Inferential statistics

are methods used to make conclusions or inferences concerning some unknown aspect of a population based on data from a sample.

population

is a collection of all possible individuals, objects, or measurements of interest

parameter

is a numerical measurement describing some characteristic of a population

sample

is a portion, or part, of the population of interest

statistic

is a numerical measurement describing some characteristic of a sample.

census

In a ______, we collect data from the entire population

Inference

is the process of drawing conclusions or making decisions about a population based on sample results

Simple random sampling

is a procedure in which each member of the population is chosen strictly by chance

raw data

data collected in original form

frequency distribution

is the organizing of raw data in table form, using classes and frequencies

Categorical frequency distributions

can be used for data that can be placed in specific categories, such as nominal- or ordinal-level data

Ungrouped frequency distributions

can be used for data that can be enumerated and when the range of values in the data set is not large.

Grouped frequency distributions

can be used when the range of values in the data set is very large.

Class limits

represent the smallest and largest data values that can be included in a class

class boundaries

are used to separate the classes so that there are no gaps in the frequency distribution.

class width

for a class in a frequency distribution is found by subtracting the lower (or upper) class limit of one class minus the lower (or upper) class limit of the previous class

point estimate

the sample statistic is considered to be a _______ of the population parameter

mean

______ of a data set is the average of all the data values.

median

_______ of a data set is the value in the middle when the data items are arranged in ascending order

mode

_____ of a data set is the value that occurs with greatest frequency.

Class mark or class midpoint

the midpoint between the upper and lower class boundaries or class limits of a class interval.

Relative Frequency Distribution

a table listing relative frequencies

Relative Frequency

can be obtained by dividing the class frequency by the total frequency

Cumulative Frequency

the total frequency of all values less than the upper class boundary of a given class interval up to and including that class

Cumulative Frequency Distribution

a table showing the cumulative frequencies