confidence interval
Wk 4 Discussion – Central Tendency [due Thurs] The attachments are screenshots of the chapters.
Post a total of three (3) substantive responses over at least two (2) separate days for full participation. These posts include your initial discussion, and two (2) replies to your classmates.
Word count is not measured; however, ensure there is enough discussion to have a substantive response.
Due by Thursday (40 points)
Initial Discussion. Respond to each of the following eight (8) questions:
Read and understand the selected learning objectives in the Lind et al. (2021) textbook.
Chapter 7
: LO7-2 Normal Probability, LO7-3 Standard Normal Probability Distribution (calculation)
Chapter 8
: LO8-1 Sampling Methods, LO8-3 Sampling Distribution of the Mean
Chapter 9
: LO9-1 Point Estimate, LO9-2 Confidence Interval for Population Mean (calculation), LO9-2 Population Standard Deviation, σ Unknown
Chapter 7
7A. What are the characteristics of a normal probability distribution?
7B. The weekly incomes of shift foremen in the glass industry follow the normal probability distribution with a mean of $3,500 and a standard deviation of $1.000.
What is the z value for the income of a foreman who earns $3,000 per week?
Chapter 8
8A. Explain why a researcher would sample a population. For instance, why take 1200 valid samples of registered U.S. voters?
8B. Describe four random sampling methods (and the advantages).
Chapter 9
9A. What exactly is a point estimate? For instance, what would be a point estimate of these five flower heights (ft.): 5, 6, 7, 8, 9
9B. A confidence interval is used in the election polls. On the CBS Evening News, it showed Candidate A at 52% and Candidate B at 45%. The margin of error was 6%. Explain how Candidate B could win.
The mean yearly income for construction works in New York has been calculated as $88,000, with a range of $85,000 to $91,000.
9C1. If a confidence interval of 95% has been calculated with respect to this data, what does that confidence interval tell us?
9C2. What is the effect on the confidence interval gap width as the sample size increases?
Instructions
| QNT- | 3 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Detailed Instructions are given on the Instructions document attached separately with this assignment. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| The instructions were created by E | x |
Question 1
–
($ thousands)
4
U.S. Television Sales
LCD TV 2014 2015 2016 2017 2018 2019 246 664 1579 3295 3962 5328.3333333333
3 Projection TV 2014 2015 2016 2017 2018 2019 3574 4351 6271 5320 6668.5 6484 Plasma TV 2014 2015 2016 2017 2018 2019 515 1590 2347 4012 4928 6343.3333333333303 Year
Sales in $ thousands
Question 2
and
responses?
11%
10%
Include the x- and y-axis labels
Percentage of Responses
Percentage of Responses No financial stress Some financial stress High financial stress Overwhelming financial stress 0.11 0.21 0.1 0.57999999999999996 Percentage of Responses
Percentage of Responses No financial stress Some financial stress High financial stress Overwhelming financial stress 0.11 0.21 0.1 0.57999999999999996
Stress Levels
Response in percentage
Question 3
,
, Good,
, or Poor)
Restaurant
Rating
s
Outstanding
Distribution is a table with two columns – Ratings and Frequency.
of Frequency
30
Good
Good
Outstanding
Outstanding
Outstanding
Outstanding
Good
Good
Good
Outstanding
Very Good
Outstanding
Outstanding
Average
Very Good
Frequency
Outstanding 12
Very Good 8
Good 7
Average 3
Restaurant Rating
Frequency Outstanding Very Good Good Average 12 8 7 3 Rating
Frequency
Question 4
Plot
on a line chart.
Revenue
Include the x- and y-axis labels
Monthly Revenue
Revenue Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 8950 10300 7300 12430 11900 12230 10480 10500 12870 11400 12996.8181818182 12772.121212121199 Month
Revenue
Question 5
Plot
Sold
and
on a scatter plot. x Cost of Goods Sold
$8,950
$10,300
$10,480
$10,500
$11,400
$11,900
$12,230 Include the x- and y-axis labels
$12,430
$12,870
$12,997
Gross Profit
Profit 179000 44783 1043000 49905 50000 95000 170000 61
0 77688 45964 81230 153822.74242424301 8950 10300 10430 10480 10500 11400 11900 12230 12430 12870 12996.8181818182 13868.939393939399
Cost of goods sold
Gross Profit
Question 6
of
Sedan
s that were sold. 150
Hybrid
20%
Sedan
15%
SUV
30%
Compact
20%
Truck
15%
Vehicle Type Sales
Hybrid
20%
Sedan
15%
SUV
30%
Compact
20%
Truck
15%
Vehicle Type Sales
Instructions
| QNT- | 3 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Detailed Instructions are given on the Instructions document attached separately with this assignment. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| The instructions were created by E | x |
Question 1
–
($ thousands)
4
U.S. Television Sales
LCD TV 2014 2015 2016 2017 2018 2019 246 664 1579 3295 3962 5328.3333333333
3 Projection TV 2014 2015 2016 2017 2018 2019 3574 4351 6271 5320 6668.5 6484 Plasma TV 2014 2015 2016 2017 2018 2019 515 1590 2347 4012 4928 6343.3333333333303 Year
Sales in $ thousands
Question 2
and
responses?
11%
10%
Include the x- and y-axis labels
Good
Percentage of Responses
Percentage of Responses No financial stress Some financial stress High financial stress Overwhelming financial stress 0.11 0.21 0.1 0.57999999999999996 Percentage of Responses
Percentage of Responses No financial stress Some financial stress High financial stress Overwhelming financial stress 0.11 0.21 0.1 0.57999999999999996
Stress Levels
Response in percentage
Question 3
,
, Good,
, or Poor)
Restaurant
Rating
s
Outstanding
Distribution is a table with two columns – Ratings and Frequency.
of Frequency
30
Good
Good
Good
Outstanding
Outstanding
Outstanding
Good
Good
Good
Outstanding
Very Good
Outstanding
Outstanding
Average
Very Good
Frequency
Outstanding 12
Very Good 8
Good 7
Average 3
Restaurant Rating
Frequency Outstanding Very Good Good Average 12 8 7 3 Rating
Frequency
Question 4
Plot
on a line chart.
Revenue
Include the x- and y-axis labels
Good
Monthly Revenue
Revenue Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 8950 10300 7300 12430 11900 12230 10480 10500 12870 11400 12996.8181818182 12772.121212121199 Month
Revenue
Question 5
Plot
Sold
and
on a scatter plot. x Cost of Goods Sold
$8,950
$10,300
$10,480
$10,500
$11,400
$11,900
$12,230 Include the x- and y-axis labels
$12,430
$12,870
$12,997
Good
Gross Profit
Profit 179000 44783 1043000 49905 50000 95000 170000 61
0 77688 45964 81230 153822.74242424301 8950 10300 10430 10480 10500 11400 11900 12230 12430 12870 12996.8181818182 13868.939393939399
Cost of goods sold
Gross Profit
Question 6
of
Sedan
s that were sold. 150
Hybrid
20%
Sedan
15%
SUV
30%
Compact
20%
Truck
15%
Vehicle Type Sales
Hybrid
20%
Sedan
15%
SUV
30%
Compact
20%
Truck
15%
Vehicle Type Sales
Instructions
| QNT- | 3 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Detailed Instructions are given on the Instructions document attached separately with this assignment. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| The instructions were created by E | x |
Question 1
–
($ thousands)
4
U.S. Television Sales, 2014 – 2019 ($ thousands)
Year 2014 2015 2016 2017 2018 2019 Projection TV 3574 4351 6271 5320 6668.5 6484 LCD TV 246 664 1579 3295 3962 5328.3333333333
3 Plasma TV 515 1590 2347 4012 4928 6343.3333333333303
Year
Sals value
Question 2
| In a survey of employees conducted by Financial Finesse Inc., | 10 | ||
| were asked about their overall financial stress levels. The following table shows | |||
| the results of this survey. | |||
| A. Plot a pie chart | |||
| B. Plot a bar chart | |||
| C. Which chart do you believe is better for readability. In particular, to 10% and | 11 | ||
| Stress Level | Percentage of Responses | The bar chart may be vertical or horizontal | |
| No financial stress | |||
| Some financial stress | 21 | ||
| High financial stress | |||
| Overwhelming financial stress | 58 | ||
| Pie chart | |||
| Include the category and percents | |||
| Bar chart | |||
| a) | |||
| b) | c) | The piechart has better readability and visibility, partcicularly for the 10% and 11% responses |
stress level analysis
Percentage of Responses
No financial stress Some financial stress High financial stress Overwhelming financial stress 11 21 10 58
Percentage of Responses No financial stress Some financial stress High financial stress Overwhelming financial stress 11 21 10 58 Stress Level
Percentage of Responses
Question 3
| Given below are the ratings of the overall dining experience ( | Outstanding | Good | Average | ||||||||||||||||||||||
| of 30 randomly selected patrons at a restaurant on a Saturday evening. | |||||||||||||||||||||||||
| Restaurant | Ratings | ||||||||||||||||||||||||
| a) Using the Pivot table in Excel, construct a frequency distribution. | Frequency | ||||||||||||||||||||||||
| Frequency Distribution is a table with two columns – Ratings and Frequency. | |||||||||||||||||||||||||
| b) Plot a bar chart using Pivot Table. | |||||||||||||||||||||||||
| Very Good | |||||||||||||||||||||||||
| Grand Total | |||||||||||||||||||||||||
Restaurant Ratings
Total Average Good Outstanding Very Good 3 7 12 8 Ratings
Frequency
Question 4
| Given below is the revenue data for an organization. | |||
| Plot | Revenue | ||
| Month | |||
| Jan | $8,950 | ||
| Feb | $10,300 | ||
| Mar | $7,300 | ||
| Apr | $12,430 | ||
| May | $11,900 | Line chart | |
| Jun | $12,230 | ||
| Jul | $10,480 | ||
| Aug | $10,500 | ||
| Sep | $12,870 | ||
| Oct | $11,400 | ||
| Nov | $12,997 | ||
| Dec | $12,772 |
Revenue
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 8950 10300 7300 12430 11900 12230 10480 10500 12870 11400 12996.8181818182 12772.121212121199 Month
Revenue
Question 5
| Axis | Variable | |||
| Plot | Cost of Goods | Gross | Profit | |
| $179,000 | ||||
| $44,783 | ||||
| $1,043,000 | $10,430 | |||
| $49,905 | ||||
| $50,000 | ||||
| $95,000 | ||||
| $170,000 | Scatterplot | |||
| $611,500 | ||||
| $77,688 | ||||
| $45,964 | ||||
| $81,230 | ||||
| $153,823 | $13,869 |
Scatter plot
Profit
179000 44783 1043000 49905 50000 95000 170000 61
0 77688 45964 81230 153822.74242424301 8950 10300 10430 10480 10500 11400 11900 12230 12430 12870 12996.8181818182 13868.939393939399 Cost of Goods
Profit
Question 6
of
Sedan
s that were sold. 150
Hybrid
20%
Sedan
15%
SUV
30%
Compact
20%
Truck
15%
Vehicle Type Sales
Hybrid
20%
Sedan
15%
SUV
30%
Compact
20%
Truck
15%
Vehicle Type Sales