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