Stat 111 Introduction to Statistics

Vocabulary flashcards for Statistics 111 lecture notes.

Statistic (as numerical facts)

Numerical facts regarding people living in a specific area.

Statistic (as investigation)

The investigation of methods for gathering, analyzing, and interpreting data.

Descriptive Statistics

Its primary concern is the description of large amounts of data, including data classification and diagrammatic representation.

Inferential Statistics

Allows us to draw conclusions about the population based on samples drawn from the population.

Quantitative Variables

Data that can be measured or counted directly, like quantity sales or wages.

Qualitative Variables

Information that is not numerical in nature, such as skin color or marital status.

Coding (Qualitative Data)

The process of assigning numerical values to qualitative variables.

Ranging/Ranking (Qualitative Data)

Arranging qualitative data in descending order of importance and assigning values in that order.

Primary Data Source

Original information gathered by the investigator for a specific study, derived from surveys.

Secondary Data Source

Pre-existing data collected by others for another purpose, often from administrative activities.

Discrete (or) ungrouped frequency distribution

Each class is distinct and separate. Non-continuity from one class to another class omits.

Continuous (or) grouped frequency distribution

Data are organised by the use of some intervals

Class Limits

The lowest and highest values that can be included in the class.

Class Interval

The size of each group of data.

Width or Size of the Class Interval

The difference between the lower and upper class limits.

Range

The difference between the largest and smallest value of the observation.

Mid-Value/Midpoint

Central point of a class interval, found by averaging the upper and lower limits.

Exclusive (continuous) method

Type of class Interval in which the class interval overlaps

Inclusive (Discrete) method

In this method the over lapping of the class intervals is voided

Open-end classes

A class limit is missing either at the lower end of the first class interval or at the upper end of the last class interval

Histogram

Also called block frequency diagram. It is a continous distribution

Frequency polygon

It is obtained by plotting the midpoints of each class interval and the corresponding frequency of that dass

Cumulative frequency Distribution (Ogive) or (CF.Curve)

obtained by plotting cumulative frequency agamist upper class boundary

Sources of statistical Errors

are the difference between the actual magnitude of the object in question and the magnitude of the estimation of the objects given by the enum

Absolute Error

This is given by subtracting the estimated value from the actual value.

Relative error (or per centage error)

This is actual error committed divide by the estimated value. When this proportion is multiplied by 100

Measure of central tendency

Measures of location or simply called averages are widely used statistically measures.

Arithmetic mean or simple mean

it is defined as the sum of the observations divided by the number of observations.

Median

in that value of the variable which divides group into two equal parts

Mode

is the value that occurs most frequently

unimodal listibution

defined as, a listibution with one mode

bimodal listibution

defined as, a listibution with two mode

Geometer mean

of n observations is the nth root of their products.

Harmonic Mean

of nitem is defied as

Measures of partition

divide data in to four, ten ad hundred equal parts respectively

Quartiles

divide data in to four equal parts when the data are arrange in order of size

Jeciles

divides the distribution in to ten equal parts

percentiles

divide a distribution in to 100 equal parts

Measures of Dispersion

always occur in size or quality always occur

Range

Difference of Largest(L) and Smallest(S), range = (L-S)

Quartile Deviation

This is also called Semi Inter quartile Range

Interquartle Range

Quartiles Deviation is haff of the difference between the first and third quartiles

Mean seviation

number of observations

Standard deviation

standard deviation is obtained by using the formula

Variance

as the mean of squared deviation of the mean from each Observation

Index number

statistical measure designed to study the relative change in a variable

Statistic (as numerical facts)

Numerical facts regarding people living in a specific area.

Statistic (as investigation)

The investigation of methods for gathering, analyzing, and interpreting data.

Descriptive Statistics

Its primary concern is the description of large amounts of data, including data classification and diagrammatic representation.

Inferential Statistics

Allows us to draw conclusions about the population based on samples drawn from the population.

Quantitative Variables

Data that can be measured or counted directly, like quantity sales or wages.

Qualitative Variables

Information that is not numerical in nature, such as skin color or marital status.

Coding (Qualitative Data)

The process of assigning numerical values to qualitative variables.

Ranging/Ranking (Qualitative Data)

Arranging qualitative data in descending order of importance and assigning values in that order.

Primary Data Source

Original information gathered by the investigator for a specific study, derived from surveys.

Secondary Data Source

Pre-existing data collected by others for another purpose, often from administrative activities.

Discrete (or) ungrouped frequency distribution

Each class is distinct and separate. Non-continuity from one class to another class omits.

Continuous (or) grouped frequency distribution

Data are organised by the use of some intervals

Class Limits

The lowest and highest values that can be included in the class.

Class Interval

The size of each group of data.

Width or Size of the Class Interval

The difference between the lower and upper class limits.

Range

The difference between the largest and smallest value of the observation.

Mid-Value/Midpoint

Central point of a class interval, found by averaging the upper and lower limits.

Exclusive (continuous) method

Type of class Interval in which the class interval overlaps

Inclusive (Discrete) method

In this method the over lapping of the class intervals is voided

Open-end classes

A class limit is missing either at the lower end of the first class interval or at the upper end of the last class interval

Histogram

Also called block frequency diagram. It is a continous distribution

Frequency polygon

It is obtained by plotting the midpoints of each class interval and the corresponding frequency of that dass

Cumulative frequency Distribution (Ogive) or (CF.Curve)

obtained by plotting cumulative frequency agamist upper class boundary

Sources of statistical Errors

are the difference between the actual magnitude of the object in question and the magnitude of the estimation of the objects given by the enum

Absolute Error

This is given by subtracting the estimated value from the actual value.

Relative error (or per centage error)

This is actual error committed divide by the estimated value. When this proportion is multiplied by 100

Measure of central tendency

Measures of location or simply called averages are widely used statistically measures.

Arithmetic mean or simple mean

it is defined as the sum of the observations divided by the number of observations.

Median

in that value of the variable which divides group into two equal parts

Mode

is the value that occurs most frequently

unimodal listibution

defined as, a listibution with one mode

bimodal listibution

defined as, a listibution with two mode

Geometer mean

of n observations is the nth root of their products.

Harmonic Mean

of nitem is defied as

Measures of partition

divide data in to four, ten ad hundred equal parts respectively

Quartiles

divide data in to four equal parts when the data are arrange in order of size

Jeciles

divides the distribution in to ten equal parts

percentiles

divide a distribution in to 100 equal parts

Measures of Dispersion

always occur in size or quality always occur

Range

Difference of Largest(L) and Smallest(S), range = (L-S)

Quartile Deviation

This is also called Semi Inter quartile Range

Interquartle Range

Quartiles Deviation is haff of the difference between the first and third quartiles

Mean seviation

number of observations

standard deviation is obtained by using the formula