Chapter 3 Flashcards
Biomedical distribution
- When you have two modes in a distribution
Correlation
- This tells us the relationship between two variables
- Three types: positive, negative, and zero
Correlation coefficient
- This is determined when describing the relationship between any two variables
Descriptive statistics
- A way to collect objective data to be interpreted
Frequency distribution
- It expresses how often a score occurs in a set of data
Interval scale of measurement
- It is a scale of measurement in which equal differences in scores represent equal differences in amount of the property measured, but with an arbitrary zero point
Mean
- It is the mathematical average of the distribution of scores
Measures of central tendency
- Mean, median, and mode
Median
- This is the middle score in a distribution
Mode
- This is the most frequently occurring score in a distribution
Multimodal distribution
- When you have three or more modes in a distribution
Negative correlation
- Variables are negatively correlated when a high score on one is accompanied by a low score on the other
Negatively skewed distribution
- More of the scores fall above the mean
Nominal scale of measurement
- Data is categorical
- It assigns observations into various independent categories and then counting the frequency of occurrence within each of the categories creates a nominal scale.
Normal curve
- A graphical representation of a normal distribution
- Sometimes called this because of its flared shape
Normal distribution
- An arrangement of a data set in which most values cluster in the middle of the range and the rest taper off symmetrically toward either extreme
Ordinal scale of measurement
- Involves the rank order system
- It is a scale in which scores indicate only relative amounts or rank order
Positive correlation
- Variables are positively correlated when a high score on one is accomplished by a high score on the other
Positively skewed distribution
- More of the scores fall below the mean
Range
- This is the difference between the high score and the low score in the distribution
Ratio scale of measurement
- It has all the properties of an interval scale with the additional property of zero indicating a total absence of the quality being measured
Skewed distribution
- It is one in which the majority of scores fall at either the high end or low end rather than the middle of a distribution
Standard deviation
- This is the spread of scores around the mean
Variance
- This is a statistical concept that tells you the spread of scores within a distribution
Zero Correlation
- No relationship between the variables
What are the three measures of central tendency?
- Mean, median, and mode
What are the measures of variance? (?)
- Standard deviation and the analysis of data in the normal curve (?)
What is/are the mode(s) in this data set: 25, 44, 45, 45, 56, 79, 83
45 - it occurs the most often
What is/are the mode(s) in this data set: 25, 44, 44, 45, 56, 79, 79, 83
44, 79 - they both occur the most often (and an equal amount)
What is the median in this data set: 25, 44, 45, 56, 79
45 - it is the middle number
What is the median in this data set: 25, 44, 45, 56
44.5 - it is the middle number
What is the mean of this data set: 25, 44, 45, 45, 56, 79
49 - this is the numbers all added then divided by 6 (the number of numbers)
What is the range of the data set in #7?
54 - this is the biggest number minus the smallest number
