Psych: Unti 1 Part 2 (STAT)

STATISTICS

X Axis

horizontal number line

Y Axis

vertical number line

Outlier

a data point that differs significantly from other observations

Measures of Central Tendency

as the number used to represent the center or middle of a set of data values

-mean, median, mode

Mean

Average, adding all numbers in the data set and then dividing by the number of values in the set

Median

middle value when a data set is ordered from least to greatest

Mode

the number that occurs most often in a data set

Range

the distance between the lowest and the highest value

Skewed Data

data that creates an uneven curve distribution on a graph

Negative skew

points left toward the negative side of the histogram

Positive skew

points right toward the positive side of the histogram

Histogram

a chart that plots the distribution of a numeric variable's values as a series of bars

Normal distribution

a probability distribution that appears as a "bell curve" when graphed

P-Value (Probability Value)

a number describing how likely it is that your data would have occurred under the null hypothesis of your statistical test

Probability Testing

The likeliness of an outcome or research result given the hypothesis

Null hypothesis

the claim that the effect being studied does not exist

Measures of Variability

how spread scores are in a distribution out

-range, variance, standard deviation, interquartile range, ect

Variance

how far a set of numbers is spread out from their average value, calculated by taking the average of squared deviations from the mean

Standard Deviation

the average amount of variability in your dataset- how far data points range from the mean

Statistical Significance

a result from data generated by testing or experimentation is likely to be attributable to a specific cause

ex: changing the color of a button from red to green will result in more people clicking on it

Inferential Statistics

The process of using data analysis to infer properties of an underlying distribution of probability

ex: birth weights of twins are generally lower than the weights of babies born alone

Empirical Rule

68-95-99.7 rule, tells you where most of the values lie in a normal distribution

Descriptive Statistics

Quantitatively describes or summarizes features from a collection of information, used to summarize and describe the main features of a dataset