Stats Final Flashcards

In a statistical study, what is the difference between an individual and a variable.

An individual is a member of the population of interest. A variable is an aspect of an individual subject or object being measured.

population:

the whole set

statistic

a number associated with a sample

sample

Part of the whole set

parameter

a number associated with a population. Ex: mean, mode, median, range.

Ordinal

Categories with a meaningful order, but no consistent interval between them. Examples: Survey responses (e.g., strongly disagree → strongly agree), Socioeconomic status (low, middle, high)-Race placements (1st, 2nd, 3rd)

Nominal

“No particular order” Examples: Gender (male, female, nonbinary)- Political affiliation (Democrat, Republican, Independent)-Hair color (blonde, black, brown)

Ratio

We can order the data, take differences, and also find the ratio between data values. For instance, it makes sense to say that one data value is twice as large as another.

Interval

Ordered values with equal intervals, but no absolute zero point. exaples: Sat scores, Iq scores, Act scores.

Mode

most frequent value in a data set

median

middle value in a data set

mean

the average of a dataset

range

the highest value- the lowest value

(Sampling distribution) use z table directly for:

“Less than” “At Most”

(Sampling distribution) Subtract from 1 for:

“Greater Than” “At least”

Alpha is:

the probability of rejecting Ho when it is true

A type I error is

The act of rejecting Ho when it is true

A type II error is

The act of not rejecting Ho when it is false.