2416483
Description
Flashcards by Amrit Bhogal, updated more than 1 year ago
|
Created by Amrit Bhogal
about 9 years ago
|
|
| Question | Answer |
| Observed Score | A score obtained from a measurement instrument. - Has strong meaning when compared with other scores |
| How do we calculate an Centered Score? | Subtracting the mean from the observed score. -ve when below the mean, +ve when above the mean |
| Sum of squares - what is it a measure of? - how is it calculated? | - A measure of variability - Calculated by squaring the centered scores and then adding them together |
| When is the sum of squares larger? | When the scores fall father from the mean |
| Sum of products - what is it a measure of? - how is it calculated? | - Measure of relationship between two variables - It is calculated by multiplying a person’s centered score on one variable by her or his centred score on the other variable, and then adding these products together |
| When is SP positive? negative? | - Positive when an increase in one variable is associated with an increase in the other variable, - Negative when an increase in one variable is associated with a decrease in the other variable. |
| Independent vs. dependent variable | Te dependent variable is the variable one wants to predict (Y), and the independent variable is the variable one uses to predict it (X) |
| Degrees of freedom | Number of scores in a set that can vary freely |
| True/false the sum of centered scores is 0 | True |
| How is variance calculated? | SS/N-1 (degrees of freedom) |
| How does the standard deviation relate to the variance? | It is the square root of the variance |
| What is the purpose of taking the square root of the variance? | To undo the initial squaring of the centered scores - Providing an estimate of variability that relates directly to the original unit of measurement. |
| True or False/ the ratio between N-1 and N approached unity as N increases | True |
| Standard Scores - What are they? - What is a common form? | - centred scores that have been scaled relative to the standard deviation - Z score |
| What does a Z score indicate? | A z score indicates the number of standard deviations that an observed score is away from the mean - Z scores have a mean of zero (like centred scores) |
| simple correlation | A standardized measure of relationship that ranges in value from −1 to 1 |
| When a simple correlation positive? when is it negative? | . It is positive when an increase in one variable is associated with an increase in the other variable, and it is negative when an increase in one variable is associated with a decrease in the other variable. |
| How is the simple correlation calculated? | A simple correlation is equal to the standardized sum of products divided by its degrees of freedom. |
| What is the standardized sum of products? | Te standardized sum of products is simply the sum of products calculated using z scores rather than centred scores |
Want to create your own Flashcards for free with GoConqr? Learn more.