Statistical Evaluation 2-3

Statistics A part of math that lets researchers organize and evaluate data

Types of Statistics Descriptive statistics Inferential statistics

Descriptive Statistics Listing and summarizing of data Typically uses graphs and averages Purpose is to describe the characteristics of a sample

Descriptive Statistics Distributions of data Are the results very different from one another (very spread out) Are the results very similar to each other (very close together/bunched up) Are the results evenly spread out

Descriptive Statistics Frequency distribution Way to see how often the same answer/result happened

Descriptive Statistics Normal curve A bell shaped cure A symmetrical curve

Descriptive Statistics Measures of Central Tendency A number that describes something about the average score Mode – most frequent score Mean – average Median – the middle score

Descriptive Statistics Measures of Variance How spread out the scores are Range – subtract the highest and lowest score Standard deviation – like an average distance of every score compared to the mean of the scores

Descriptive Statistics Correlation coefficients Describes the direction and strength of a relationship between two things Positive correlation Negative correlation

Inferential Statistics Purpose – to see if the data supports their hypothesis or if the results just happened by chance

Inferential Statistics Probability and Chance Tests to determine if the results were just by chance or not

Inferential Statistics Statistical Significance Less than 5% possibility of chance

Inferential Statistics

Inferential Statistics