Exam 1: The Nature of Statistics

The members of a board of directors have the following roles: president (P), vice president (V), secretary (S), treasury (T), and fundraiser (F). Consider these board members to be a population of Interest. The possible samples (without replacement)of size two that can be obtained from these Five board members are as follows. $\mathrm { P } , \mathrm { V } \text { P,S P,T P,F V,S V,T V,F S,T S,F T,F }$ If a simple random sampling method is used to obtain a sample of two of the board members, what are the chances of selecting the secretary and the treasurer?

Identify the study as an observational study or a designed experiment. -At one hospital in 1992, 674 women were diagnosed with breast cancer. Five years later, 88% of the Caucasian women and 83% of the African American women were still alive.

The table below shows the average income by age group for the residents of one town in the year 1998. The average incomes for each age group are estimates based on a sample of size 100 from Each group. Age group Average income 18-24 \ 17,180 25-39 \ 26,661 40-54 \ 32,471 55-70 \ 25,960 Over 70 \ 18,241 Classify the study as either descriptive or inferential.

Geologists have an interest in the structure and the history of the earth. A geologist can go back in time by drilling deep into the ground, retrieving a core sample, estimating the ages of the various Layers, and examining the composition. A timeline can be built of the entire area from where the Core sample was drilled. A geologist may retrieve several core samples to confirm the history of The earth's structure in that sampled area. Mountains, lakes, and unstable ground can easily Impede a simple random sampling of a desired geographical area, therefore what is the most Realistic sampling method that represents the actual drillings, comparisons, and scientific Examinations of several core samples within the same geographical area?

A magazine publisher always mails out a questionnaire six months before a subscription ends. This questionnaire asks its subscribers if they are going to renew their subscriptions. On average, Only 7% of the subscribers respond to the questionnaire. Of the 7% who do respond, an average of 47% say that they will renew their subscription. This 7% who respond to the questionnaire are Known as what?

100,000 randomly selected adults were asked whether they drink at least 48 oz of water each day and only 45% said yes. Identify the sample and population.

List all possible samples from the specified population. -Given a group of students: Allen (A), Brenda (B), Chad (C), Dorothy (D), and Eric (E), list all of the possible samples (without replacement)of size four that can be obtained from the group.

The spell-checker in a desktop publishing application may not catch all misspellings (e.g. their, there)or correctly interpret the spellings of proper names. Jackie is an expert editor and can Proofread extremely quickly. Jackie is hired by a book publisher to check the spelling of every Word in the latest proof of a history book. With regard to Jackie's assignment, what is the Population?