1. For each of the following statistical investigations, (1) suggest an appropriate graphical display for summarizing the data and (2) identify a statistic (numerical summary) that could be used to describe the data. [2 marks each]

a) A random sample of 150 customers of a retailers in Vancouver is obtained to study the relationship between the household income of the customer (less than $45,000, $45,000 to $89999, and over $90,000 or higher) and whether he or she has a store credit card (Yes or No).

Graphical display:

Statistic (numerical summary):

b) The financial controller of a mid-size wholesaler wants to develop a statistical model to estimate the amount of time it takes to process invoices in his accounts receivable department. Data were collected from the past 30 days. For each day, the number of invoices processed and completion time (in minutes) were obtained.

Graphical display:

Statistic (numerical summary):

c) A nutritionist obtained a sample of 35 soft drinks and measured the sugar content (in milligrams per ounce) for a study in weight management.

Graphical display:

Statistic (numerical summary):

A. The entire set of subjects that we are interested in. B. An adjective/description/measurement used to describe a subject C. An entity that we take measurements or information on D. A subset of a population E. A numerical summary of a population F. A numerical summary of a sample G. Information gathered for the purpose of experiment or survey Variable Subject Population Parameter Statistic Sample DataQuestion 1 Recall the univariate EDA tools by summarizing them in a table like the one below. Univariate EDA Numerical Summaries Graphical Summaries Quantitative (a) what are they? (b) what are they? Categorical (c) what are they? (d) what are they? Question 2 We will cover tools for bivariate quantitative EDA later on. We'll do some quantitative vs categorical EDA in this lab. Bivariate EDA Numerical Summaries Graphical Summaries Quantitative us Quantitative Correlation (Ch 3) Scatterplot (Ch 3) Quantitative us Categorical see la (a) what is it? Categorical us Categorical Frequencies & rel. frequencies Odds Ratio (binary vs binary) Contingency Table (Ch 8). In a typical experiment, the radioactivity of a radioactive sample is measured for one minute. It is then measured for three additional one-minute periods. separated by two minutes. So data are recorded at 1.. 3Ir 5, and ? minutes after the start of the rst counting period. The measurement units are counts. Here are the data For one of these experiments: Viiri {a} Find the correlation between the radioactive counts and the time after the start of the rst counting period. {Use decimal notation. Give your answer to three decimal places.) r=o {b} Does the correlation give a good numerical summary of the relationship between these two variables? Because there is an obvious curve in the data, the correlation is not a good numerical summary for \"-' these variables. If) Correlation is a good numerical summary here because the value of r is close to 1 or -1. If) Correlation is a good numerical summary here because the scatterplot is strongly linear. A(n) is a numerical summary of a sample. A(n) is a numerical summary of a population. parameter continuous variable discrete variable statistic