biostats lecture 1

Why do we need statistics?

to make sense of data by collecting and organizing it, natural variation vs real difference 

What do inferential statistics do?

they generalize from a sample to a large group of subjects, predict outcomes, and signal to noise ratios 

What is an example of descriptive statistics?

median, mode, and range 

Define an independent variable.

the variable that is being manipulated 

Define a dependent variable.

the outcome of interest, the change in response to the independent variable 

Define each of the following data types

Nominal

Ordinal

Interval

Ration

nominal: categories that are named with no order 

Ordinal: ordered categories, but their differences cannot be considered equal 

Interval: equal distance between values, where 0 is arbitrary 

interval and Ratio can be treated the same 

Ratio: equal intervals between values and a meaningful zero 

Parametric variables?

Interval, Ratio

Non-parametric variables?

Nominal, Ordinal

Why is it important to know what kind of data you have (NOIR) and whether they are independent or dependent variables?

It is important because it determines which statistical analysis methods are appropriate and valid for the data

Why is it a good idea to always graph your data?

It detect errors and provides a visual representation of complex info that makes it easier to understand

When should you use a table rather than a graph?

When there are many variables/ the graph is confusing.

Why are 3d graphs and pie charts a bad idea?

looks bad, disorts the data and creates confusion