stats chapter 1,2 & 3
If your score on your next statistics test is converted to a z score, which of these z scores would you prefer: minus−2.00, minus−1.00, 0, 1.00, 2.00? Why?
The z score of 2.00 is most preferable because it is 2.00 standard deviations above the mean and would correspond to the highest of the five different possible test scores.
Based on sample data, newborn males have weights with a mean of 3223.5 g and a standard deviation of 646.8 g. Newborn females have weights with a mean of 3007.7 g and a standard deviation of 747.3 g. Who has the weight that is more extreme relative to the group from which they came: a male who weighs 1600 g or a female who weighs 1600 g?
male z score= -2.51 female z score = -1.88 the male has the weight that is more extreme.
A value at the center or middle of a data set is a(n) _______.
measure of center
The measure of center that is the value that occurs with the greatest frequency is the _______.
mode
_______ are sample values that lie very far away from the majority of the other sample values.
outliers
Identify the symbols used for each of the following: (a) sample standard deviation; (b) population standard deviation; (c) sample variance; (d) population variance.
same standard deviation: s population standard deviation:σ sample variance: s2 population variance: σ2 .
When testing a new treatment, what is the difference between statistical significance and practical significance? Can a treatment have statistical significance, but not practical significance?
Statistical significance is achieved when the result is very unlikely to occur by chance. Practical significance is related to whether common sense suggests that the treatment makes enough of a difference to justify its use. It is possible for a treatment to have statistical significance, but not practical significance.
Determine whether the data described below are qualitative or quantitative and explain why. The prices of a gallon of gasoline at the gas stations of a certain cityThe prices of a gallon of gasoline at the gas stations of a certain city.
The data are quantitativequantitative because they consist ofthey consist of counts or measurements.counts or measurements.
Given these temperatures, what issue can be addressed by conducting a statistical analysis of the data?1,2,3,4,5: 8am: 97, 98.5, 97.6,97.7, 98.7 12pm: 97.6, 97.8 98.0, 98.4, 98.4
The data can be used to address the issue of whether there is a correlation between body temperatures at 8 AM and at 12 AM.
A defunct website listed the "average" annual income for Florida as $35,031. What is the role of the term average in statistics? Should another term be used in place of average?
The term average is not used in statistics. The term mean should be used for the result obtained by adding all of the sample values and dividing by the total number of sample values.
Methods used that summarize or describe characteristics of data are called _______ statistics
descriptive
Determine whether the value is from a discrete or continuous data set. Number of coins in a jar is 78Number of coins in a jar is 78
discrete
A _______ is a graph of each data value plotted as a point.
dotplot
A magazine published a list consisting of the state tax on each gallon of gas. If we add the 50 state tax amounts and then divide by 50, we get 27.3 cents. Is the value of 27.3 cents the mean amount of state sales tax paid by all U.S. drivers? Why or why not?
No, the value of 27.3 cents is not the mean because the 50 amounts are all weighted equally in the calculation, but some states consume more gas than others, so the mean amount of state sales tax should be calculated using a weighted mean
