Term
|
Definition
| Something that when measured, has no fixed value. |
|
|
Term
|
Definition
| Method where the degree of relationship between at least 2 variables is assessed. |
|
|
Term
|
Definition
| Research method that allows a researcher to establish a cause and effect relationship through manipulation of a variable and control of the situation. |
|
|
Term
|
Definition
| Variable manipulated by researcher. Cause. |
|
|
Term
|
Definition
| Variable measured by researcher. Effect. |
|
|
Term
|
Definition
| Definition of a variable in terms of the operations a researcher uses to measure or manipulate it. |
|
|
Term
|
Definition
| Stats used to describe/summarize characteristics of a set of scores. |
|
|
Term
|
Definition
| Procedures for drawing conclusions about a population based on data collected from a sample. |
|
|
Term
|
Definition
Nominal
Ordinal
Interval
Ratio |
|
|
Term
|
Definition
| Measure of variables that are categorical in nature. Using #'s as arbitrary labels. Ex: 1 = male, 2 = female. |
|
|
Term
|
Definition
| Measuring a quantity in rank order |
|
|
Term
|
Definition
Measured on a scale with equally sized intervals.
No true zero point |
|
|
Term
|
Definition
Height, weight, length, time, income.
True zero point |
|
|
Term
|
Definition
| Exist in "whole units" Ex: Family size income, gender. Numbers must eventually stop. |
|
|
Term
|
Definition
| Exist theoretically. Age, time, height, weight. |
|
|
Term
|
Definition
Variable for which the scores represent a change in quantity.
Histograms |
|
|
Term
|
Definition
| categorical variable for which each value represents a category. Bar graph |
|
|
Term
| Symmetrical Distributions |
|
Definition
| All normal distributions are symmetrical, but not all symmetrical distributions are normal. |
|
|
Term
|
Definition
| Theoretical frequency distributions with the following characteristics: Unimodal, symmetrical, identical values for mean, median mode, bell shaped. Normal distributions are the normal curve |
|
|
Term
|
Definition
| Positive and negative. Distribution is not symmetrical. |
|
|
Term
|
Definition
| Degree of peakedness vs. flatness |
|
|
Term
|
Definition
| Peaked, taller then normal |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Flatter, more spread out. |
|
|
Term
| Measures of central tendency |
|
Definition
Descriptive statistics that summarize a set of scores by determining where the center of a distribution is.
Mean, Median, Mode |
|
|
Term
|
Definition
| Descriptive statistics indicating the extend to which the scores in a distribution tend to differ. Measures of "spread" |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Systematically underestimate the true value of population variance. Misses tend to be in one direction. (Dart board) |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Defines range of values between the 25th and 75th percentile. |
|
|
Term
|
Definition
| Distance each score is from the mean of the set of scores |
|
|
Term
|
Definition
|
|
Term
|
Definition
5 number graphical displays.
MIN
25th
Median
75th
Max |
|
|
Term
|
Definition
| tables where all of the scores are listed along with the frequency with which each occurs |
|
|
Term
|
Definition
| Table where scores are grouped into intervals and listed along with the frequency. |
|
|
Term
|
Definition
| The score at which a given % of the scores in a distribution fall at or are below. Ex: Median is 50% percentile, so 50% of scores are at or below it. |
|
|
Term
|
Definition
| Score that indicates the percentage of people who scored at or below a given raw score |
|
|
Term
|
Definition
| scores pile up near low end of distribution resulting in a positive skew. |
|
|
Term
|
Definition
| scores pile up near high end of distribution resulting in a negative skew. |
|
|
Term
|
Definition
| Theoretical distributions that give, over all possible samples of size N. In a normal distribution, x bar where the deviations are |
|
|
Term
| Standard error of the mean |
|
Definition
| The average amount that the sample means deviate from the population mean. Give indication of accuracy of a sample mean |
|
|
Term
| Estimated standard error of the mean |
|
Definition
| Estimate of the standard deviation of the sampling distribution |
|
|
Term
|
Definition
| The "other two" possibilities combine to be the null |
|
|
Term
|
Definition
| The researcher's hypothesis |
|
|
Term
|
Definition
|
|
Term
| Critical values for z test |
|
Definition
| One or two tail. One tail is where direction is predicted and 2 tail is where no direction is predicted. One tail is more powerful. |
|
|
Term
| Characteristics of a t distribution |
|
Definition
| When N is small and mean? Is unknown, the sampling distribution of the mean is symmetrical, but wider than normal. Population variance is not known. (single sample) T distribution is a family of curves that differ for each N. |
|
|
Term
| Independent samples t test |
|
Definition
| Used for comparing samples means from 2 independent groups of scores. Ex: 10 people in 2 groups. One get placebo, one get drug. |
|
|
Term
| Related (Dependent) samples t test |
|
Definition
| Used to compare the means of two related samples of scores. Ex: 10 people in 2 groups. People get both the drug AND the placebo |
|
|
Term
| How to determine critical values for t test |
|
Definition
|
|
Term
|
Definition
| Post hoc test procedure when F is significant. HSD= Indicates how much 2 means need to differ from one another to be significantly different. |
|
|
Term
|
Definition
|
|
