HONORS STATISTICS
CH1
In an observational study, researchers simply observe characteristics and take measurements, as in a sample survey.
In a designed experiment, researchers impose treatments and controls and then observe characteristics and take measurements.
Data from a sample of citizens of a certain country yielded the following estimates of average TV viewing time per month for all the citizens.
Answer: Inferential, because the statistics are used to make inference about the population.
* 50 kids are divided into 2 groups. One is exposed to a vid on bullying. The other isn’t. After one week, both groups are questioned about their attitudes about violence. This is a designed experiment
5 state officials:
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No, since the data is qualitative
4. Paved | 92 | 106 | 86 | 91 | 106 | 88 | 74 | DIRT | 69 | 58 | 50 | 57 | 60 | 93 | 109 |
Range of paved is .. 106 – 74 = 32 --- highest – lowest
Range of dirt is 109 – 50 = 59
Standard Deviation: Paved: A) All the values added together = x, then that value squared = x^2 B) Each value squared and then added together (92^2 + 106^2 + …)
Finding the answer: Square root of B – (A/number of values or N) N-1
Do the same for Dirt with other numbers
5. 10 numbers given 67 148 153 77 127 91 66 146 100 97 rearrange data in ascending order 66 67 77 91 97 100 127 146 148 153 a) obain quartiles:
Q2 = median --- 97+ 100/ 2 = 98.5
For Q1, Q3, split the data in to two parts
66 67 77 91 97 100 127 146 148 153 the median of the lesser data is Q1 and the median of the greater data is Q3
b) quartiles suggest the 25% of samples are less than Q1, 25% between Q1 and Q2, 25% between Q2 and Q3, and 25% greater than Q3
c) IQR = Q3- Q1
*number of units contained in the middle 50% of the samples span roughly (IQR answer) units
D) % number summary
Minimum, Q1, Q2, Q3, Maximum *The middle 50% has the greatest
a. The time (in years) it takes a sample of students to graduate college (Mean)
4. Calculate the following measures of central tendency for the set of cube measurement data. Show your work or explain your procedure for each.
6. Based on questions 3, 4, and 5 is the mean or median a better estimate for the parameter of interest? Explain your reasoning.
1. By hand, compute the mean, median, and mode for the following set of 40 reading scores:
d. It should appear in the tail signifying a negative relationship, with .05 in that tail.
6. Based on questions 3, 4, and 5 is the mean or median a better estimate for the parameter of interest? Explain your reasoning.
5. When is it more appropriate to use the median as a measure of center rather than the mean? Why?
The performance had to be forced in a bell curve like curve where high performers could be maximum of 14%; Achievers (A) min 70%; Low Achievers (L) min 7% and Unacceptable (U).
7. The data set for this problem can be found through the Pearson Materials in the Student Textbook Resource Access link,
c. Note the ways in which the means and standard deviations differ, and speculate on the possible meaning of these differences, presuming that they are representative of U.S. governors and large corporations’ CEOs in general.
The method used for the study was quantitative, this was chosen rather than a qualitative as this deals with facts and figures and is an investigatory type of study. This can be either experimental or non experiment. Experimental is the method used in this study which looks at cause and effect, and involves dependent and independent variables. (Balnaves and Caputi, 2001) A qualitative study can be described as interpretive which deals with personal thoughts and feelings (Flick, 2009).
The mean is the average of all numbers. The Liberal’s mean is 50.76, Conservative’s mean is 38.45 and NDP’s mean is 54.57. The NDP’s mean is higher than Liberal and Conservative. It means that the NDP is more popular than the other two parties and the Conservative, which has the lowest mean, is the less popular party among these three parties. In the data center, means and medians are often tracked over time to spot trends which power cost predictions. The statistical median is the middle number in a sequence of numbers. The median is 56 for Liberal, 38 for conservative and 60 for NDP. As we can see, the mean and the median are related and following each other. When the mean is higher the median is higher too and when the mean is lower the median is lower too. To find the median, organize each number in order by size; the number in the middle is the median. Standard Deviation is a measure that is used to quantify the amount of variation or dispersion of a set of data values. A low standard deviation indicates that the data points tend to be close to the mean of the set, while a high standard deviation indicates that the data points are spread out over a wider range of values. The standard deviation for Conservative is 31.4 which is higher in relation to the other two parties. The standard deviation for Liberal is 28.4 and for NDP is 27.1. The data points in the conservative party spread out over a wider range of values in relation to the other two parties. The standard
6. To calculate Q1 and Q3 , you must first arrange the observations in increasing order to find the median, Q1 is the median of the observations whose position in the list is to the left of the overall median, Q3 is the median of the observations whose position in the list is to the right of the overall median.
Find the mean, median, SD & IQR for the data in (1) after it has been transformed
The box plot of the appendix of 11, 12 and 13 represents the results on lower (bottom) and higher (top) quartile. The band located inside the box and is always the second quartile (the median). Moreover, the box plot has two lines where are extending vertically on the top and on the bottom of the box (whiskers). The top of the upper and lower whiskers shows the upper and lower extreme.