Which of the following correctly describes the nature of discrete quantitative variables? a. They are characteristics possessed by persons or objects, called elementary units, in which we are interested. b. They can assume values only at specific points on a scale of values, with inevitable gaps between successive observations. c. When dealing with such variables, we can count all possible observations and, with some exceptions, that count leads to a finite result. d. both (a) and (c) e. all of these

Which of the following situations would indicate a negative association?

1-The following information is collected from a customer satisfaction survey conducted by a restaurant to help them drive customer loyalty and Gender Number of food items bought Number of visits to the restaurant in a week Satisfaction on the variety of food and beverages available Classify each variable as categorical or numerical and determine its measurement scale.

14. In a regression context, under what situation is the predicted value for Y equal to the mean of Y? a) when the correlation between Y and X is positive b) when the correlation between Y and X is negative c) when the correlation between Y and X is zero d) when we try to predict Y in the complete absence of X e) a and d f) c and d g) none of the above, the predicted value for Y is only equal to the mean when X is equal to 0

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5. Is ultrasound a reliable method for determining the gender of an unborn baby? The data on 100 births is given below. a. What is P(F)? Write your answer as a decimal. b. What is P(F|Pm)? Round your answer to 4 decimal places. c. True or False: F and Pm are independent. Write either TRUE or FALSE

2.3.1 Which is the highest level of measurement possible for each of the following variables? a. Daily high temperature for a given year in Chicago b. Marital status of the applicants for a particular job c. Class standings at a university (freshman, sophomore, etc.) d. Colors of roses e. Weights of all American-made cars f. Number in attendance per day at a particular high school g. Birthdays of people in a certain group

Q1. A psychologist conducted a study on the relationship between introversion and shyness. The values are results for scales of introversion and shyness. High positive scores on each scale indicate high introversion or shyness; and high negative scores indicate low introversion or shyness. Data collected from 10 people as follows: Introversion 4 -7 -1 0 6 7 -4 -9 -5 8 Shyness 11 -7 -1 -3 0 7 -1 -8 -1 5 a) Compute the correlation coefficient relating introversion and shyness scores. b) Find the regression equation which predicts introversion from shyness. c) What introversion score would you predict from a shyness score of 7?

1. SUGAR Listed below are measured weights (mg) of sugar in Domino packets labelled as containing 3500 mg (or 3.5 g). Are the data qualitative or quantitative? What is the level of measurement of the data (nominal, ordinal, interval, or ratio)? Before any rounding, are the weights discrete or continuous? Given that the weights are from Domino sugar packets selected from a much larger population, are the weights a sample or a population? If we calculate the mean of the listed values, is the result a statistic or a parameter? 3511 3516 3521 3531 3532 3545 3583 3588 3590 3617 3621 3635 3638 3643 3645 3647 3666 3673 3678 3723 2. FREQUENCY DISTRIBUTION Using the data from Exercise 1, construct a frequency distribution using a class width of 50 mg and a first class with a lower class limit of 3500 mg. 3. HISTOGRAM Use the frequency distribution from Exercise 2 to construct a histogram. Use class midpoint values for the horizontal scale.