Unformatted text preview: STAT 350, 2012 Spring Quiz #1 1. When data are collected in a statistical study for only a portion or subset of all elements of interest, we are using a: ____C__________. A. Population B. Statistic C. Sample Certain characteristics of the objects in a population may be __A___ such as type of malfunction, student ID #, or it may be _B___ such as age of a graduating engineer. A. Categorical B. Quantitative _C____ 2. 3. Which of the following statements is incorrect? A) Constructing a histogram for discrete data (measurements) entails subdividing the measurement axis into a suitable number of class intervals or classes, such that each observation is contained in exactly one class. B) The reaction time to a particular stimulus is an example of a continuous variable. C) Constructing a histogram for discrete data is generally not different from constructing a histogram for continuous data... D) The total area of all rectangles in a density histogram is 100%. 4. The probability mass function of a discrete random variable x is defined as p(x) = ax for x = 1,2,3,4, then the value of a is 1/10. If p(x) = ax for x = 0, 2, 3, 4, then a = 1/9. If p(x) = ax for x = 1, 2, 3, 5, then a = 1/11. 5. f(x) is a density function. For f(x) = 2x on [0,1], What is the probability that x <= 0.5? For f(x) = 3x^2 on [0,1], P(x <=0.5) =? For f(x) = x+ 0.5 on [0,1], P(x<=0.5) =? .25 .125 .375 ...
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This note was uploaded on 02/06/2012 for the course STAT 350 taught by Professor Staff during the Spring '08 term at Purdue.
- Spring '08