Chapter 13 Flashcards
Population
Any group of objects, not just human populations.
Sample:
A subset of a population.
Representative sample:
A sample that accurately reflects the characteristics of the population as a whole.
Random sample:
A sample in which every member of the population has an equal chance of getting in.
Population:
Any group of objects, not just human populations.
Sample:
A subset of a population.
Representative sample:
A sample that accurately reflects the characteristics of the population as a whole.
Random sample:
When every member of the population has an equal chance of getting into the sample.
Mean:
A statistical average that is determined by adding the numerical values in the data concerning the examined objects, then dividing by the number of objects that were measured.
Median:
A statistical average that is determined by locating the value that separates the entire set of data in half.
Mode:
A statistical average that is determined by locating the value that occurs most.
Standard deviation:
A measure of the amount of diversity in a set of numerical values.
How to Calculate Standard Deviation
Step 1: Calculate the mean value.
Step 2: Calculate the difference between each value in the set and the mean value.
Step 3: Multiply each difference by itself (square each difference).
Step 4: Add the results of the squaring process in step 3.
Step 5: Divide the result of step 4 by one fewer than the number of members in the set.
Step 6: The square root of the total variance is the standard deviation.
What If the Results Are Skewed?
Not all data are quantifiable; measuring devices may not provide “objective” results.
Statistical analysis can lead to new questions, new disagreements, new interpretations.