Statistics1.txt
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Nominal is
 Characterized by data that consist of names, labels, or categories only.
 Data cannot be arranged inan ordering scheme.

Ordinal measurement is
Data ordered, differences between data values cannot be determined or are meaningless

Interval data is
 differences are meaningful
 ratios are meaningless
 No "zero" starting point.

Ratio Measurement
 Is the interval level with a natural zero starting point.
 Differences and ratios are both meaningful.

The complete collection of all individuals or items to be studied.
Population

Quantiative data
data that can be counted.

Qualitative Data
cannot be counted. Quality includes things like hair color, sex, etc.

Every member of the population has an equal chance of being selected. Every sample of the same size has an equal chance of being selected.
Random Sample

What are the four types of sampling techniques?
 Stratified sampling
 Systematic sampling
 Cluster sampling
 Convience sampling

A collection of data from every member of the population is a
census

A subcollection of members selected from a population is a
sample

A numerical measurement describing some characterisic of a population is
a parameter.

A numerical measurement describing some characteristic of a sample is
a statistic

Data consisting of numbers representing counts or measurements is
Quantitative or numerical data

Data consisting of names or labels that are not numbers representing counts or measurements is
Categorical or qualitative or attribute data

When the number of possible values is either a finite number or a "countable" number the data is
discrete data

Data that results from infinitely many possible values that correspond to some continuous scale that covers a range of values without gaps, interruptions, or jumps is call what type of data?
Continuous (numerical)

What is a sample called when the respondents themselves decide whether to be included?
Voluntary response

What are the four levels of measurement in classifying data?
 Nominal
 Ordinal
 Interval
 Ratio

What two types of studies are there for obtaining data?
 Observational
 Experimental

When we observe and measure specific characteristics, but don't attempt to modify the subjects being studied it is called _________________ study.
an observational study

We apply some treatment and then proceed to observe its effects on the subjects. This is called what type of study?
Experimental

A sample of n subjects selected in such a way that every possible sample of the same size n has the same chance of being chosen is called
a simple random sample.

Members from the population are selected in such a way that each individual member in the population has an equal chance of being selected is called what type of sample?
Random Sample

What is the sampling method called where selecting members from a population in such a way that each member of the population has a known but not necessarily the same chance of being selected?
Probability sample

We select some starting point and then select every kth (such as every 50th) element in the population is called what type of sampling method?
Systematic sampling

When we simply use results that are very easy to get is called what type of sampling?
Convenience sampling

When the population is subdivided into at least two different subgroups so that subjects within the same subgroup share the same characteristics (such as gender, or age), then we draw a sample from each subgroup what type of sampling is this?
Stratified sampling

When data is first divided into sections then randomly select some of those sections, choosing all the members from those selected sections is called what type of sampling?
Cluster sampling

What are the 5 ways data can be produced?
 Sampling
 Experimental
 Simulation
 Census
 Surveys

Professional pollsters and government researchers collect data by using some combination of basic sampling methods is called_______________
Multistage sampling

What are the three types of observational studies of collecing data?
 crosssectional study
 retrospective or casecontrol study
 prospective (longitudinal or cohort) study

_____________ study is done back in time to collect data over some past period.
Retrospective

When data is measured at one point in time it is called
crosssectional study

When data is taken by going forward in time and observe groups sharing common factors it is called
Perspective or longitudinal or cohort study.

When a technique is used in which the subject doesn't know whether he or she is receiving a treatment or placebo is called
Blinding

When the subjects don't know if they are receiving the treatment or a placebo and the doctors or administratiors also don't know who is receiving the treatment or placebo it is called
a double blind study

The difference between a sample result and the true population result is called
a sampling error

When the sample data are incorrectly collected, recorded, or analyzed it is called ________________ error.
a nonsampling error

What are the five characteristics of data?
 Center
 Variation
 Distribution
 Outliers
 Time

A respresentitive or average value that indicates where the middle of the data set is located is called
the center

A measure of the amount that the data values vary is
variation

The nature or shape of the spread of the data over the range of values is called
distribution

Sample values that lie very far away from the vast majority of the other sample values is called
outliers

What shows how a data set is partitioned among all of several categories or classes by listing all of the categories along with the number data values in each of the categories called
Frequency distribution

The smallest numbers that can belong to the different classes in a frequency distribution is called
lower class limits

The largest numbers that can belong to the different classes in a frequency distribution is called
upper class limits

The numbers used to separate the classes, but without the gaps created by class limits is called
class boundaries

The values in the middle of the classes is called
class midpoints.

How are class midpoints found?
 (lower class limit) + (upper class limit)
 2

What is the difference between two consecutive lower class limits or two consecutive lower class boundaries in a frequency distribution called?:
Class width

class frequency
sum of all frequencies = ?
relative frequency

(Class frequency)
(sum of all frequences) x 100% =
percentage frequency

What is the sum of the frequencies for a class and all previous classes called?
cumulative frequency

What 12 types of graphs are there?
 Frequency polygon
 Histogram
 Relative frequency polygon
 Ogive
 Dotplots
 Stemplots
 Bar graphs
 Multiple bar graphs
 Pareto chart
 Pie chart
 Scatterplot
 Timeseries graph

Graphs using bars of equal width to show frequencies of categories of qualitative data are called
Bar graphs

In bar graphs the horizontal scale identifies the different ________ of __________ data.

What are the five items for interpreting Histograms? (CVDOT)
 Center of the data
 Variation of the data
 Distribution of the data
 Outliers of the data
 Time (cannot be seen in a histogram)

The horizontal scale for histograms uses what?
class boundaries of class midpoints

The vertical scale for histograms uses what?
class frequencies

How is a Relative frequency histogram different from a histogram?
has the same shape and horizontal scale as a histogram but the vertical scale is marked with relative frequencies instead of actual frequencies.

What graph uses line segments connected to points located directly above class midpoint values?
Frequency Polygon

A(n) ______ is a line graph that depicts cumulative frequences.
Uses class boundaries along the horizontal scale, and cumulative frequences along the vertical scale.
Useful for determing the number of values below some particular value.
Ogive ("ohjive")

A graph in which each data value is plotted as a point or dot along a scale of values and equal values are stacked?
dot plot

What are the four advantages of stemplots?
 1. Turning on its side the distribution of values can be seen
 2. Data from the original list is retained and can be reconstructed.
 3. Construction is a quick way to sort the data in order
 4. Can be expanded to include more rows asnd can be condensed to include fewer rows.

What type of graph has two or more sets and is used to compare two or more data sets?
multiple bar graph

What is a bar graph for qualitative data, with the stipulation the bars are arranged in descending order according to frequencies. Vertical scale represents frequencies or relative frequences. Horizontal scale identifies different categories of qualitative data, called.
Pareto Chart

What type of graph dipicts qualitative data as slices of a circle, in which the size of each slice is proportional to the frequency count for the category?
Pie chart

What is a graph called that plots as paired (x,y) quantitative data with a horizontal x axis and a vertical y axis?
Scatterplot

A _________ graph is a graph of time where quantitative data has been collected at different points in time?
time series

A ________ is a graph consisting of bars of equal width drawn adjacent to each other(without gaps). The horizontal scale represents classes of quantitative data values and the vertical scale represents frequenci3es. The heights of the bars correspond to the frequency values.
histogram

A ___________ is a graphic version of a frequency distribution. It is used to learn about CVDOT.
histogram

A(n) _________ is useful for determining the number of values below some particular value.
ojive

Which graphs are used for categorical data:

A time chart is a data display whose main point is to examine __________________.
trends over time.

Which graphs are used for numerical data?

How is a histogram interpreted?
 1. Symmetry: skewness, bellshape, etc.
 2. Amount of variability in the data.
 3. Where is the center of the data (approximately)

How is a boxplot interpreted?
 shows information about the distribution, variability, and center of a data set.
 1. Symmetry: skeweness.
 2. variability
 3. center of data