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Our tables rating individual companies will be more valuable
to you if you know how the data were gathered and how they should be
interpreted.
We regularly survey area CHECKBOOK and Consumer
Reports subscribers for their feedback on services they have used. We
sometimes also survey subscribers to various other websites and publications
and survey a sampling of other area consumers. On our surveys, we ask consumers
to rate their experiences with companies they had most recently used on several
aspects of service. Our ratings tables show the percent of each company’s
surveyed customers who provided a rating of “superior” (as opposed to
“inferior” or “adequate”) for questions on our survey. We sometimes also report
the percent of surveyed customers who rated each company “adequate” or
“superior” (as opposed to “inferior”) for the “overall quality” question on our
survey.
We have included on our ratings tables all of the companies
for which we received at least 10 ratings on our customer surveys. If a company
is not listed on our ratings tables, it simply means we did not receive at
least 10 ratings for it.
Since many companies were rated by rather small numbers of
raters, small differences between two firms in the percentage of raters who
gave a particular rating (say, “superior”) should be ignored. The table below
gives a rough guide to minimum differences you should look for in deciding on
one company over another.
When using these survey data, remember that the questions
are to some degree subjective and that the differences among companies might be
explained by differences in the personalities, backgrounds, critical standards,
and other characteristics of the raters or by biases these raters might have.
For many of the services we evaluate, our ratings tables
show the number of complaints filed against each company with government
offices of consumer affairs in Fairfax, Howard, and Montgomery counties; the
Office of the Attorney General for the District of Columbia; the Consumer
Protection Division of the Maryland Attorney General’s Office; and the Virginia
Office of Consumer Affairs. These complaint counts are for a two-year period.
Where we were able to, we have also reported on our ratings
tables a complaint rate for each company, calculated by dividing the number of
complaints by our measure of the number of full-time-equivalent employees who
perform non-commercial work for the company. These complaint rates are intended
as a rough way to take into account volume of work and the fact that companies
that do more work are exposed to a greater risk of incurring complaints.
When using the complaint information, keep in mind that
complaints are not always justified; sometimes the customer is unreasonable.
Also, be aware that some companies may be at greater risk than others of
incurring complaints because of the specific types of business they do. And
remember that the measure of business volume we use in calculating complaint
rates (our estimate of the number of full-time-equivalent employees who perform
residential work) is at best a very rough indicator.
We always recommend that you look for substantial
differences in complaint counts and rates. We also advise giving little weight
to complaint counts if the total count against a company is less than three or
four.
To compute our price index scores, we calculated an average
price for each job or item for all the companies that quoted on that job or
item. Next we compared each company’s price to the average. One company might
come in at 120 percent of the multi-company average for a particular job, and
another company might come in at 90 percent. We took each company’s percentage
score on each job or item, standardized it, and assigned a weight to each job
or item, based on our judgment. We then averaged the standardized, weighted
percentage scores to find how the company compared to other companies overall.
Finally, we multiplied this overall percentage score by a flat dollar amount,
say, $100.
The price index score, then, is intended to indicate the
relative prices we found for the companies, adjusted to the base of this flat
dollar amount. These index scores are imperfect for various reasons: for
instance, the jobs or items checked may not be representative; the weighting of
various jobs or items in the index may not accurately reflect typical
expenditure patterns; and the number of jobs or items is small.
All of the data must be interpreted in view of timeliness. Our
customer survey data are from surveys conducted from January 2006 to March
2013. Survey respondents were asked to report on experiences in the preceding
year. Our data on complaints for the government offices of consumer affairs are
for a two-year period between October 1, 2010 and September 30, 2012. The data
from our surveys of companies were collected from November 2012 to February
2013. Our price data were collected from August to November 2012.
For the most part, our tables include companies for which we
collected 10 or more ratings on our customer survey during the customer survey
period mentioned above, but we do not report data for periods prior to
companies’ changes of name and ownership. As a result, some large companies are
not listed at all. If only name or ownership changed, we do report the data.
Changes subsequent to the dates listed above may not be taken into account.
We give checkmarks to companies that score highest on a
scoring system that we devise for each service field. Our scoring systems
weight the various data in our tables and text based on our subjective judgment
of their importance. Since the scores are based entirely on information
presented, you can apply your own subjective judgments, and decide whether you
prefer companies we have not given checkmarks. Where we do not have important
data on a company, we cannot give our checkmark.
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