Module 3 Lesson 2: Review of Statistics, Part 1 Flashcards
What are test norms based on?
Test norms are based on elementary notions from descriptive statistics.
What is a science built around?
A science is built around the variables it studies.
In how many levels can variables be described?
Variables can be described at three levels of generality.
What is a variable at its most general level?
At the most general level, a variable is a construct.
What is a construct?
Here, we give verbal descriptions and definitions of the variable.
What are example of constructs?
For example, intelligence may be defined as the ability to manipulate abstract symbols; maladjustment may be described as either the feeling of or objective evidence of significant difficulties in conducting ordinary life activities.
What is the second level of a variable?
At a second level, we measure the variable. This is the operational definition of the variable.
What field deals with the operational definition?
The field of psychological testing deals with these measures. It studies the characteristics of the measures and catalogs existing measures.
What is the third level of a variable?
At the third level, we get raw data.
What is raw data?
These are the numbers that result from application of the measures.
What does statistics operate on?
Statistics operate on raw data, the most specific level for a variable. Since raw data come from our measures, statistics provide the summaries and treatments of the measures (tests) in which we are interested. Of course, all the while we are most interested in the variable at the level of a construct.
What are the two major divisions of statistics?
The two major divisions of statistics are descriptive and inferential statistics.
What is descriptive statistics?
Descriptive statistics help to summarize or describe this raw data to aid our understanding of the data. Most frequently, the data come from a sample of individuals. We are mainly interested in knowing about the population from which this sample was drawn.
What is inferential statistics?
Inferential statistics help us to draw conclusions—inferences—about what is probably true in the population based on what we discovered about the sample.
