Chapter 11: Descriptive Statistics Flashcards
Value that describes a population.
Parameter
A value that describes a sample.
Statistic
List the two types of statistics (2).
- Inferential
2. Descriptive
Difference between descriptive and inferential statistics?
- Descriptive; Characteristics of data set (organize and summarize)
- Inferential: Generalization to population
What do descriptive statistics do (2)?
- Transform large groups of numbers into more manageable forms.
- Permit the researcher to meaningfully describe many scores with a small number of indices.
What do organization and summary of descriptive stats involve?
- Organization involves: ranking, frequency distributions, tables, graphs
- Summaries involve: Measures of central tendency and variability
Statistic that is used to indicate the amount of variability in participants’ responses (E.g.: range, SD).
Variance
What are the disadvantages of range?
- Two sets of data could be very different but still have the same range.
- These two data sets have the same range, yet the variability in the scores is very different.
Convey information about a distribution by providing information about the average or most typical score.
Central Tendency
Examples of central tendency include (3).
- Mean
- Median
- Mode
When the distribution has more extreme scores at one end than at the other, the mean, median, and mode are different. What does this do/indicate in a graph?
Skewness
When reporting only a few means in a research report, how to researchers usually present them?
Within the text
When reporting several means in a research report, how do researchers usually present them?
Within a table or graph
The amount of dispersion of scores about the mean score.
Variability
What does a measure of variaibility give us an idea about?
It gives us a better idea of how diverse the scores are in the group.
