Introduction to Psychometrics Flashcards
What is measurement?
The assigning of numbers to individuals in a systematic way as a means of representing properties of the individuals
What are the three major purposes of measurement theory?
- Describe, categorize, and evaluate the quality of measurement
- Improve the usefulness, accuracy, and meaningfulness of instruments
- Propose methods for developing new and better measurement instruments
What are the four scales of measurement?
- Nominal
- Ordinal
- Interval
- Ratio
What are the two major divisions of statistics?
- Descriptive
2. Inferential
Which division of statistics is used to make inferences about a population parameter?
Inferential
What is the major difference between continuous and discrete variables?
Continuous variables can take on any value within a given range including values that are not whole numbers
What are the three measures of central tendency?
- Mean
- Median
- Mode
What are some measures of variability?
- Range
- Interquartile range
- Average deviation
- Varianc
- Standard deviation
Why is a ratio scale called a “ratio” scale?
Because it is the only measurement scale that can be used to create meaningful ratios.
What do you get when you square the correlation between x and y?
The proportion of variance in y that is accounted for by a linear relationship with x.
As you increase the % used to formulate your confidence interval, what happens to the confidence interval?
It becomes larger to accommodate more scores
