Statistics homework help
Statistics homework help. Stat 116 – Assignment #1 — Due Wednesday, May 13 11:30am, 2020 Convert your
solution to one Word or PDF file and Submit it to D2L
1. A sample 50 students in Victoria randomly selected. The researchers recorded whether or not
the participants are smokers, their age, and number of semesters they have been in school.
(a) (1 mark) Identify the population of interest to the researcher
(b) (3 marks) Fully classify each variable listed above (qualitative or quantitative; discrete
or continuous; nominal or ordinal)
(i) smokers:
(ii) age:
(iii) number of semesters:
2. (1 mark) Mail carriers of a large city are divided into four groups according to gender (male
or female) and whether they walk or ride their routes. Then 10 are selected from each group
and interviewed to determine whether they have been bitten by a dog in the last year. What
type of sampling technique was used?
3. (2 mark) Find the difference bewteen: Cluster Sampling vs Stratified Sampling.
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4. (2 marks) A histogram of the calorie content of 46 brands of cereals is shown below. Describe
the distribution (be specific and refer to all 3 characteristics).
5. (2 marks) A study has found that male children born to women who smoke during pregnancy
run a risk of violent and criminal behaviour that lasts well into adulthood. What conclusions
can we draw from this study? Explain your reasoning in 1-2 sentences.
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6. (13 marks) The calorie content of 12 cereals is given below.
130 210 190 190 115 190 130 210 240 210 140 80
(a) Calculate the following to two decimals (you may do this by hand or on the calculator. If
you use your calculator, include the formula that would be required to do the calculation
by hand.)
(i) Mean (ii) Median
(iii) Q1 (iv) Q3
(v) IQR (vi) Range
(vii) Standard deviation (vii) Variance
(b) Draw a boxplot of the data. (Don’t forget the scale)
(c) Check for any outliers using the 1.5IQR rule.
(d) Is the distribution symmetric, skewed left, or skewed right? Justify your answer using
the calculations from part (a) and the boxplot from part (b).
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7. (6 marks) Is there a relation between Quantity Sold (Output) and Price (Input). In other
words: can we predict Quantity Sold if we know Price and Advertising? Answer the following
questions. The follows tables and graph are excel output.
(a) Give the linear regression equation.
(b) Interpret the slope of this regression equation.
(c) Give the coefficient of determination and explain what it means.
(d) Does the residual plot indicate any problems with the model? Explain.
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