Unit 3 – Collecting Data
Notes 1 – Planning a Study
Unit 3 – Collecting Data
Notes 2 – Potential Problems with Sampling
Unit 3 – Collecting Data
Notes 3 – Selecting Random Samples and an Introduction to Experiments
Unit 3 – Collecting Data
Notes 4 – Experimental Design
100

the entire group we want information about 

population

100

Samples are __________________ if they are systematically not representative of the desired population.

biased 

100

  what are the things on which the experiment is done

experimental units 

100

The explanatory variables in an experiment

factor 

200

a part of the information we actually examine to gather information about the population 

sample

200

When a sample is comprised entirely of volunteers or people who choose to participate, the sample will typically not be representative of the population

voluntary response 

200

When the experimental units are toman beings

subjects 

200

The various groups the factors take

level 

300

collects data from every individual in the population 

census 

300

occurs when some groups in the population are left out of the process of choosing a sample 

undercoverage 

300

A specific experimental condition applied to the units

treatment 

300

when the subject does not know what treatment they are recieving to remove the power of suggestion 

binding 

400

observes individuals and measures variables of interest 

observational study 

400

occurs when an individual chosen for a sample cant be contacted or refuses to respond 

nonresponse 

400

A study if done to try and find the correlation between verbal and math SAT scores. The scientist wants to use the verbal score to predict the math score.

Observational study 

Explanatory - verbal score 

response - math score 

400

experiments in which the subject and administrator do not know who recieves what treatment 

double bind 

500

deliberately imposes some treatment 

experiment 

500

bias caused by the behavior of the respondent or interviewer 

response bias 

500

Some breast cancer patients were given each a new treatment. The patients were closely followed to see how long they lived following surgery.

experiment 

explanatory - new treatments 

response - length of life 

500

________ group is treated identically in all respects to the group receiving the treatment except that the members of the control group do not receive the treatment.

Control