Probability and Statistics

A movie with a 4 star rating is twice as good as one with a 2 star rating

the ratio level of measurements does not apply

What is statistics?

the science of conducting studies to collect, organizes, analyze, summarize and draw conclusions from data

Data come in ___ basic​ types, qualitative and quantitative. Qualitative​ (or categorical) data consist of values that can be placed into nonnumerical categories. Quantitative data consist of values representing counts or measurements.

two

the salaries (in dollars) of actor

ratio

a sample is the:

set of people or things from which the data are obtained

numerical data

statistics are _________ ____ that we work with -- it's the science of using these data to learn about our world and make conclusions

raw data is

the individual measurements collected

observational unit

the object that we are collecting information from is called the ___________ _____

Description of Quantitative (Numerical)

- takes on numerical values & refer to the quantity, size ex. age, income #, visits to the clinic last month, # of hours of study and so on

What are the two distinct types of data?

Qualitative (or Categorial) and Quantitive (or Numerical_

data (or variable)

The different types of information we collect for each student is called:

nominal level of measurement

The nominal level of measurement is characterized by data that consist of​ names, labels, or categories only. The data are qualitative and cannot be ranked or ordered.

ordinal level of measurement

The ordinal level of measurement applies to qualitative data that can be arranged in some order​ (such as low to​ high). It generally does not make sense to do computations with data at the ordinal level of measurement.

The types of climates for different regions (tropical, temperature, arid, etc.)

They are qualitive because they don't count or measure anything

A survey asked people about their party affiliation and recorded the responses as 1 for​ Democrat, 2 for​ Republican, 3 for​ Independent, and 4 for anything else. The survey found that the average​ (mean) party affiliation is 2.5.

This statement does not make sense​ because, while the data are coded with numeric​ quantities, the data are not quantitative in nature.​ Thus, it does not make sense to find an average of the responses.

Los Angeles reached a temperature of 100degreesF ​today, which was twice as hot as the 50degreesF in Denver.

This statement does not make sense​ because, while the data are​ quantitative, the corresponding measurement has an arbitrary zero​ point, implying that ratios between values are not meaningful.

customer satisfaction ratings (unsatisfied, satisfied, very satisfied)

ordinal

a sample statistic is:

a number that describes a characteristic of a​ sample

a population parameter is:

a number that describes a characteristic of the​ population

The population is the:

complete set of people or things being studied

What type of data can take on any value in a given interval? (height, time it takes for you to talk from your room to your car)

continuous

What type of data can take on only particular, distinct values and not other values in between? (number of steps you take from your room to your car)

discrete

The weight classes of professional boxers (lightweight, middleweight, etc.)

ordinal

Description of Qualitative (Categorical)

- can be grouped into different categories ex. gender (m or f), eye colors, outcomes of surgery, brand of cars or phones and so on