stats final

what is a null hypothesis?

its a hypothesis where no variables influence change

what is an alternative hypothesis?

its a hypothesis where a variable(S) influence change

what is the mean?

the average numbers of a data set

what is the mode?

the mode is the most recurring number of a data set

what is the median?

the middle number in a data set that has been organized chronologically

what is the range?

the highest number subtracted by the lowest number in a data set

what is normal distribution?

 is a bell-shaped, symmetrical distribution in which the mean, median, and mode are all equal.

Give an example of normal distribution.

height of the population

What size of sampling is used to get accurate results?

larger

What is random sampling?

 every single member of a population is chosen randomly, merely by chance

What is convenience sampling?

dependent on the ease of access to subjects such as surveying customers at a mall or passers-by on a busy street

What type of chart is best used for ANOVA tests?

scatter plots

What are line graphs used for?

used for variables that change over time like investment income & temperatures; shows frequencies

What is a p-value?

The probability that the result is due to sampling error or chance 

What p-value did we use this semester?

0\.05

What does it mean if the p-value is < 0.05?

it has significance

What does it mean if the p-value is > 0.05

it is has no significance

What is a t-test?

Looks for a difference between the means of 2 groups

Example of what a t-test could be ran on.

average lifespan in a specific town vs country average

What does a ANOVA test do?

 is used to test the difference between the means of two groups or more on a single variable

What is regression?

 helps you **predict** the effects of the independent variable on the dependent one.

What is correlation?

tells us if two things (variables) are related in some way, and how strong the relationship is.

correlation doesnt mean causation

How is a positive correlation depicted?

Closer to +1.0 = stronger positive correlation 

What shows negative correlation?

Closer to -1.0 = negative correlation 

List examples of correlation.

height vs weight and ice cream sales vs temperature