• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/54

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

54 Cards in this Set

  • Front
  • Back

Data Analysis

Describing the dataset by by computing a small number of statistics that characterize various aspects of the data.

4 purposes of statistical analysis?

1. Summarize data


2. Help us to understand


3. Show patterns


4. Interpret patterns

5 types of statistical anaylsis

1. Descriptive


2. Inferential


3. Differences


4. Associative


5. Predicted



(Progressively more complex and usually combined when used)

Descriptive analysis

Ex. Mean, median, mode, standard deviation, and range.



Portrays the "typical" respondent to reveal a general pattern of responses. Summary.



Used early and become the foundation for subsequent analysis.

Inference analysis

Ex. Standard error and null hypothesis.



Determines population parameters, test hypothesis, and estimates population values.



Generalize results of the target population.

Difference analysis

Ex. t-test of differences and analysis of differences.



Determines differences between two percentages or two or more means for groups in the sample.



Association analysis

Ex. Correlation and cross tabulation



Determines simple relationships, if they are related in a statistical way, and by how much.

Predictive analysis

Ex. Multiple regression



Finds complex relationships for variables, forecast future events, and determines how several independent variables influence a key dependent variable.


2 sets of measures used to describe information used in a sample

Central tendency- typical response, single piece of into.



Variability- measures describing how similar or dissimilar responses are from typical ones, set of values.


2 key questions while using descriptive measures

1. What one number best represents the variable?


2. How well does that one number represent the variable in question?

3 measures of central tendency and define

Mode- value that occurs most often.



Median- value whose occurrence lies in the middle of an ordered set of values; halfway point.



Mean- average, must be computed.

3 measures included in variability

1. Frequency distribution


2. Range


3. Standard deviation



(tells how close or apart measures are)

Frequency (percentage) distribution

Number or percentage of times a different value appears in a particular set of values (occurrence).


Range

Max and min values in a set of numbers. Does not tell us how often these values occur.

Standard deviation

Degree of variation or diversity in the values. (normal or bell shaped curve)



xi each individual observation


x_ mean

With a bell shaped distribution _________% of the value lies within ____________ times the standard deviation away from the mean.

95%


+- 1.96

Why is the squaring operation in the standard deviation formual used?

To avoid the cancellation effect.

Variance

Standard deviation squared.

With the bell shaped curve, how will the curve look with a small standard deviation vs a large standard deviation?

Small- greatly compressed or high peak


Large- flat because it is stretched out.

Nominal scale

"What is your gender?"



Mode



Frequency/percentage distribution

Ordinal scale

"Rank from 1st to 5th choice"



Median



Cumulative percentage distribution

Interval scale

"On a scale of 1 to 5, how much..."



Mean



Standard deviation/range

Ratio scale

"How many times did you..."



Mean



Standard deviation/range

Average in descriptive measure

Include. Place in column close to variable descriptions and arrange in an order.

Median, mode in descriptive measure

Don't include.


Standard deviation in descriptive measure

Typically include, if they are mostly equal don't include.

Minimum, maximum in descriptive measure

Include if data set has several diff variables, don't report if they are the same.

Frequencies in descriptive measure

Include if researcher wants to note something about the sample (very small with great affect).



Very close to variables.

Percent in descriptive measures

Include, very close to variables.

Mode in descriptive measure

Highlight, but if obvious do not report. Largest percentage group i usually readily apparent.

Statistics

Values computed from a sample. (p)

Parameters

Values computed from a complete census that are considered to be precise and valid measures of the population. (pie sign)

Inference

Form of logic in which you make a general statement about an entire class based on what you have observed about a small set of members of that class.

Statistical inference

Sample size and statistic are used to make an estimate of the corresponding population parameter (large samples are more accurate than small ones).

Statistical inference is based on what to determine what?

Based on sample size and variability to determine the amount of sampling error.

2 types of statistical inferences

Parameter estimation and hypothesis testing.

Parameter estimate

Used to approximate the population value (parameter) through the use of confidence intervals.

Hypothesis testing

Used to compare the sample statistic with what is believed (hypothesized) to be the population value prior to undertaking the survey.



Used to accept or reject hypothesis based on sample evidence.

Parameter estimation

Using sample info to compute an interval that describes the range of a parameter such as the population mean or percentage.

3 values that parameter estimation uses

1. Population mean/percentage


2. Standard error of the statistic


3. Desired level of confidence

Standard error

Measure of the variability in a sampling distribution based on what is believed to occur were we to take a multitude of independent samples from the same population.

Does the formula for mean standard error differ from a percentage standard error?

Yes.

The standard error will be ___________with larger sample sizes and ___________ with smaller sample sizes.

Smaller


Larger

2 things the standard error takes into account

Sample size and variability in sample.

50-50 split

Great variability.



Has a larger standard error than 90-10 split when sample size is the same.

Population parameters are estimated with the use of _______________________.

Confidence intervals

Confidence intervals

Degree of accuracy desired by the researcher and stipulated as a level of confidence in the form of a range with a lower and upper boundary.

Most commonly used level of confidence

95%, 1.96

A 99% confidence interval is always ___________ than 95% confidence interval if all other factors are equal.

Wider

A sample statistic is usually a ____________ or a _____________.

Mean


Percentage

Hypothesis

Expectation

Hypothesized population parameter

Value can be determined using either a percentage or a mean.

Sampling distribution concept

Our sample is one of many contributing to the bell shaped curve.



**Crux of statistical hypothesis testing.

2 tests of a hypothesized population parameter value

1. Test of a hypothesis about a percentage


2. Test of a hypothesis about a mean