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Rhythm Guitar

LEARN THE CHORDS: This is a great way to
practice chords for those of us just learning (or
perpetually learning) to play the guitar. It is one
thing to hear music, and another to read and play
the music. I particularly like the fact that I can go
at my own pace and then try it out on a real
instrument. Make this the year you finally learn to
play the guitar—this app is a great place to start.
CREATE YOUR OWN CHORDS: This is a bit
beyond me at the moment, but I can use this app to
create new chords. (Whether anyone else wants to
hear them is another matter.) The creator/editor is
very easy to use, and you can put together a bunch
of chords into a progression quickly. The progression
editor is straightforward, and includes samples so
you can see how a progression is composed.

Andrometer

Have you ever wondered how far it
is to that house you see on the top of
the hill? Or how far you’d have to
swim to make it across the lake?
Andrometer allows you to measure
the approximate distance between
you and an object, or the height and
width of something you see on the
horizon. So how tall is that building
you always see on your way to work?
You can get a pretty good approxi-
mation by installing Andrometer.

MEASURE IT: This app works
best if you you are outside where
there is good GPS reception. If you
want to measure the width of a
building, simply click on Width,
take a snapshot of one corner of
the building, then walk 20 meters
and snap the other corner. The
accelerometer and geomagnetic
sensor will do the calculations for
you.

DETAILS OR SUMMARY: Once
you measure something, you can
view either the details or the
summary of that item. I like to see
both, and fortunately they are only
a click away. This app is better for
measuring larger objects like
buildings, rather than smaller, up-
close objects.

The word economy comes from the Greek word for “one who manages a house-
hold.” At first, this origin might seem peculiar. But, in fact, households and
economies have much in common.
A household faces many decisions. It must decide which members of the
household do which tasks and what each member gets in return: Who cooks din-
ner? Who does the laundry? Who gets the extra dessert at dinner? Who gets to
choose what TV show to watch? In short, the household must allocate its scarce re-
sources among its various members, taking into account each member’s abilities,
efforts, and desires.
Like a household, a society faces many decisions. A society must decide what
jobs will be done and who will do them. It needs some people to grow food, other
people to make clothing, and still others to design computer software. Once soci-
ety has allocated people (as well as land, buildings, and machines) to various jobs,

it must also allocate the output of goods and services that they produce. It must
decide who will eat caviar and who will eat potatoes. It must decide who will
drive a Porsche and who will take the bus.
The management of society’s resources is important because resources are
scarce. Scarcity means that society has limited resources and therefore cannot pro-
duce all the goods and services people wish to have. Just as a household cannot
give every member everything he or she wants, a society cannot give every indi-
vidual the highest standard of living to which he or she might aspire.
Economics is the study of how society manages its scarce resources. In most
societies, resources are allocated not by a single central planner but through the
combined actions of millions of households and firms. Economists therefore study
how people make decisions: how much they work, what they buy, how much they
save, and how they invest their savings. Economists also study how people inter-
act with one another. For instance, they examine how the multitude of buyers and
sellers of a good together determine the price at which the good is sold and the
quantity that is sold. Finally, economists analyze forces and trends that affect
the economy as a whole, including the growth in average income, the fraction of
the population that cannot find work, and the rate at which prices are rising.
Although the study of economics has many facets, the field is unified by sev-
eral central ideas. In the rest of this chapter, we look at Ten Principles of Economics.
These principles recur throughout this book and are introduced here to give you
an overview of what economics is all about. You can think of this chapter as a “pre-
view of coming attractions.”

PRINCIPLE #1: PEOPLE FACE TRADEOFFS
The first lesson about making decisions is summarized in the adage: “There is no
such thing as a free lunch.” To get one thing that we like, we usually have to give
up another thing that we like. Making decisions requires trading off one goal
against another.
Consider a student who must decide how to allocate her most valuable re-
source—her time. She can spend all of her time studying economics; she can spend
all of her time studying psychology; or she can divide her time between the two
fields. For every hour she studies one subject, she gives up an hour she could have
used studying the other. And for every hour she spends studying, she gives up an
hour that she could have spent napping, bike riding, watching TV, or working at
her part-time job for some extra spending money.

Or consider parents deciding how to spend their family income. They can buy
food, clothing, or a family vacation. Or they can save some of the family income
for retirement or the children’s college education. When they choose to spend an
extra dollar on one of these goods, they have one less dollar to spend on some
other good.
When people are grouped into societies, they face different kinds of tradeoffs.
The classic tradeoff is between “guns and butter.” The more we spend on national
defense to protect our shores from foreign aggressors (guns), the less we can spend
on consumer goods to raise our standard of living at home (butter). Also important
in modern society is the tradeoff between a clean environment and a high level of
income. Laws that require firms to reduce pollution raise the cost of producing
goods and services. Because of the higher costs, these firms end up earning smaller
profits, paying lower wages, charging higher prices, or some combination of these
three. Thus, while pollution regulations give us the benefit of a cleaner environ-
ment and the improved health that comes with it, they have the cost of reducing
the incomes of the firms’ owners, workers, and customers.
Another tradeoff society faces is between efficiency and equity. Efficiency
means that society is getting the most it can from its scarce resources. Equity
means that the benefits of those resources are distributed fairly among society’s
members. In other words, efficiency refers to the size of the economic pie, and
equity refers to how the pie is divided. Often, when government policies are being
designed, these two goals conflict.
Consider, for instance, policies aimed at achieving a more equal distribution of
economic well-being. Some of these policies, such as the welfare system or unem-
ployment insurance, try to help those members of society who are most in need.
Others, such as the individual income tax, ask the financially successful to con-
tribute more than others to support the government. Although these policies have
the benefit of achieving greater equity, they have a cost in terms of reduced effi-
ciency. When the government redistributes income from the rich to the poor, it re-
duces the reward for working hard; as a result, people work less and produce
fewer goods and services. In other words, when the government tries to cut the
economic pie into more equal slices, the pie gets smaller.
Recognizing that people face tradeoffs does not by itself tell us what decisions
they will or should make. A student should not abandon the study of psychology
just because doing so would increase the time available for the study of econom-
ics. Society should not stop protecting the environment just because environmen-
tal regulations reduce our material standard of living. The poor should not be
ignored just because helping them distorts work incentives. Nonetheless, ac-
knowledging life’s tradeoffs is important because people are likely to make good
decisions only if they understand the options that they have available.

PRINCIPLE #2: THE COST OF SOMETHING IS
WHAT YOU GIVE UP TO GET IT
Because people face tradeoffs, making decisions requires comparing the costs and
benefits of alternative courses of action. In many cases, however, the cost of some
action is not as obvious as it might first appear.