The calculation the lower upper fence yields the actual minimum maximum

BIOSTATS 540 – Fall 2022 2. Data Visualization Solutions – Art of Stat Users (v 10/2/22) Page 1 of 8

Unit 2 – Data Visualization
Solutions – version 10/2/2022
Art of Stat Users

b)By any means you like, construct a bar graph summarization of these data. Include a title and label your axes.

c)State the facts of your bar graph.

BIOSTATS 540 – Fall 2022 2. Data Visualization Solutions – Art of Stat Users (v 10/2/22) Page 2 of 8

__ 1a) Frequency/relative frequency table In Art of Stat, choose your options at left

BIOSTATS 540 – Fall 2022 2. Data Visualization Solutions – Art of Stat Users (v 10/2/22) Page 3 of 8

Question #2

A study examining the health risks of smoking measured the cholesterol (mg/dL) levels of people in two independent groups:

Right click to download: https://people.umass.edu/biep540w/datasets/cholesterol_540.xlsx

sol_visualization art of stat.docx

	211	209	284
	216	196	288
	200	209	280
225	256	243	200
213	246	225	237
	267	232	216
	243	200	155
	271	230	309
	280	217	305
287	217	246	351
200	280	209	351

2b. Histogram for nonsmokers ONLY

- -

- Online webapps > explore quantitative data > at top, select tab MULTIPLE GROUPS

- > at left enter data: YOUR OWN > at number of groups: 2

sol_visualization art of stat.docx

BIOSTATS 540 – Fall 2022 2. Data Visualization Solutions – Art of Stat Users (v 10/2/22) Page 6 of 8

Cholesterol (mg/dL) was measured in n=43 smokers and n=33 non-smokers. Among smokers, cholesterol ranged from 155 mg/dL to 351 mg/dL, with a mean and standard deviation of 238 mg/dL and 38.5 mg/dL, respectively. Among non-smokers, cholesterol ranged from 160 mg/dL to 328 mg/dL, with a mean and standard deviation of 235 mg/dL and 44.4 mg/dL, respectively. In both groups, the mean and median values were similar, suggesting that the distributions are each symmetric around their central values. Inspection of the histograms confirms this.

__ 2e. Interpretation

sol_visualization art of stat.docx

BIOSTATS 540 – Fall 2022 2. Data Visualization Solutions – Art of Stat Users (v 10/2/22) Page 7 of 8

Smokers (n=43)	Non-Smokers (n=33)

__ 3b. HACK for you Art of Stat users! Two hacks actually.

Hack #1 - The best way to obtain what you need to complete the table is to construct a side-by-side boxplot.

	Smokers	NON-Smokers
Number in group, n =	43	33
P25 = Q1 = Lower Quartile =	211.5	209.75
P50 = Q2 = Median Quartile =	230	238
P75 = Q3 = Upper Quartile =	264.75	264
Interquartile Range (IQR) =	53.25	54.25
1.5* IQR=	79.875	81.375
Value of Lower Fence = P25 – 1.5 IQR	131.625	128.375
Lower Whisker = smallest observation that is greater than lower fence	155	160
	344.625	345.375
	309	328
	none	none
	351	none

Dear Class – Some notes:
(1) I hovered over the box plot to get more exact figures
(2) Art of Stat is showing whiskers, but is calling them “fences”
(3) Sometimes, the calculation of the lower (or upper fence) yields the actual minimum (or maximum), as occurred here.

(4) I calculated the 1.5*IQR by hand

sol_visualization art of stat.docx