Unit 1 Statistics

Mostly vocab lmfao

statistics

deals with the collection, analyzing, organizing, and summarizing of data

Descriptive statistics

organizing and summarizing data

• graphing

• using numbers (mean, median, and mode)

Inferential statistics

have a conclusion/prediction of a population

parameter vs statistics

a paremeter represents the whole population and statistics represent a sample

variables + types

a characteristic of interest for each subject/thing

• numerical

• categorical

data

actual value of variable

• quantitative

  • discrete: rigid numbers/integers

    • bar graph: seperated

  • continuous: decimals

    • bar graph: connected

• qualitative

three types of sampling

• stratified

• cluster

• systematic 

stratified sampling

divided into groups called “strata“ and then take a proportion from each (the proportions don’t have to be equal)

cluster sampling

divide the population into “clusters“ and then randomly select some whole clusters (w/all the numbers)

systematic sampling

randomly select a starting point and take every nth member of the data rom a listing of the population

non random sampling/convient sampling

using results that are readily available

levels of measurements

quantitative

• nominal scale

• ordinal scale: order matters

qualitative:

• interval scale *no absolute zero/end*

• ratio scale *has an absolute zero/end*

Frequency

a number of times a value occurs

relative frequency (RF)

The ratio of the number of times a value of the data occurs in the set of all outcomes to the total number of outcomes

cumulative relative frequency 

The cumulation of the previous relative frequencies

explanatory variable

it causes change to another variable

response variable

effected variable

treatment

the different values of the explanatory variable

blinding

participants do not know the treatment 

double blindning

participants and experimenters don’t know the treatment

lurking variable

it is not measured, yet effects the response and explanatory variables

confounding variable

a measured variable, effects the response and explanatory variables