regard@ttidcc.UUCP (Adrienne Regard) (07/16/85)
>I found the following interesting uses (abuses?) of statistics in >last night's copy of the local newspaper. >1) When you see statistics being quoted, check for ways in which they > might have been exaggerated to support some political viewpoint. > >2) When you quote statistics yourself, make sure they are reasonably > complete, and really support the viewpoint that you claim they > support, 'cause there will always be some prick like me, waiting > to point out the flaws. If you fudge the stats and get caught > at it, you ruin your own credibility. >David Canzi How about the Newsweek article re single parents that showed bar graphs on men/women of various races who were single parents. The graphs comparing previous years-to-present for the women (in the over 50% range) were approximately the same height as the graphs for the men (in the less-than- 10% range). The _intent_ of the graphs were to illustrate the differences between women of various races over the years, and (separately) between men of various races over the years, but the _effect_ created was that number of male-single-heads-of-household was approximately equal to female-single- heads-of-households. I guess we better shoot the graphics makers. BLAM! Three pie charts were presented, showing how time is divided into free time, paid work, and unpaid work (usually housework), for three groups of people: housewives, employed men, and unemployed men. The numbers in each wedge of the pie charts were probably percentages, since they add up to values near 100. The sizes of the wedges in the pie charts did not accurately reflect the values of the numbers. The following table shows who has how much free time, according to the numbers, and according to measurement of the pie chart wedges: housewives employed men employed women by the numbers 33% 34% 24% by wedge sizes 33% 46% 17% Ie. the pie charts appear to be deliberately distorted to make the womens' lot seem worse than it really is, and the mens' lot look better. A bar graph was presented showing unemployment rates for men and women in various countries. In most countries, except the USA and Japan, unemployment was higher for women (in Italy and France, extremely so). Lest the reader be fooled by the nice figures for the USA and Japan, the author of the article included a comment to the effect that "In Europe only 42% of women looking for work are registered as unemployed." THE CORRESPONDING PERCENTAGE FOR UNEMPLOYED MEN WAS NOT PROVIDED, and the European figure for "unofficially" unemployed women may be larger than the American and Japanese figures for the same. Another chart showed that the percentage of the work force consisting of women has increased only slightly (from 31% to 35%) since 1950, and not at all (stuck at 35%) over the last decade. The cute diagram illustrates 35% with a picture showing 12 men and 4 women for 1975, 15 men and 5 women for 1985. Ie. the picture looks worse than the numbers, just as in the pie charts. (No interpretation of the possible causes of this 35% ratio was offered.) Another chart was presented showing that women in Africa do somewhat more than a fair share of agricultural labour, and 95% of domestic work. No indication is given as to what percentage of the total amount of work performed is agricultural or domestic, and how much is the man's share of other kinds of work. Thus, the figures given almost certainly exaggerate the degree to which women are being overworked in Africa. A litle bit of advice to you all: "With the exception of victimless crimes (which need not concern us here) every single crime committed in this nation of ours involves a victim." -- San Francisco Chronicle
tonyw@ubvax.UUCP (Tony Wuersch) (07/17/85)
Those Newsweek statistics for men and women sound really
gross. There's a recent book by Edward Tufte called
"The Visual Display of Quantitative Information" which
is far and away the best book on what good and bad statistics
look like that I know.
One of its principles is never mix up your scales; another
is keep it simple. Anyhow, it's a great book. This Newsweek
example should have gone in it as a classic boner.
Tony Wuersch
{amd,amdcad}!cae780!ubvax!tonyw