Developing a Hedonic Regression Model for VCRs in the U.S. CPI
William Thompson
Background
The Bureau of Labor Statistics (BLS) is continuing with its research effort to improve
the estimation of quality change for selected items in the Consumer Price Index (CPI).
Some experts believe that the CPI overstates the rate of inflation for products that are
rapidly improving in quality. Unfortunately a measure of quality-adjusted price change
faced by consumers cannot be directly observed in the marketplace. Hedonic regression
analysis, however, offers one way to estimate price values for individual characteristics
of an item. The estimated price values can then be used to differentiate between pure
price change and price change due to quality differences between old and replacement items
in the CPI sample. If we are successful in the modeling effort, we can account for a
greater number of price changes realized by consumers even when new product introductions
are marked by technological improvements.
The inclusion of the video cassette recorder (VCR) in this research effort is linked to
the perception that there may be some quality bias in the price index for this item. Also,
the success of earlier hedonic research for VCRs suggests that VCRs should be included in
the continuing effort to develop hedonic regression models for the purpose of adjusting
for quality change in the CPI index.
The VCR was introduced twenty-five years ago and has become a staple in American
households. The market place for VCRs is populated by a relatively large number of brands
and a vast number of models with numerous features and characteristics. The purpose of
this research is to identify VCR features and characteristics that are valued by the
consumer and determine how they contribute to the market price of the product. Using
hedonic regression analysis, parameter estimates are developed that serve as an indication
of the relative price value of specific features or characteristics in the overall price
of the VCR. The VCR data consist of current CPI data, as well as special pricing
observations to augment the CPI sample and add robustness to the research effort. The data
were collected by CPI representatives, and information on the items was supplemented by
secondary sources, including Internet sites, consumer magazines, and manufacturer
advertisements.
The Modeling Process
The sample of VCR prices used in monthly CPI estimation was insufficient for regression
modeling purposes. Based on current CPI sampling procedures, CPI statisticians designed a
supplemental sample for hedonic modeling purposes only. The new sample added 296
observations in addition to the 243 observations from the CPI sample. The final sample
included 217 specially collected observations and 243 observations from the CPI sample.
The field data collectors were unable to collect data for 26 percent of the supplemental
sample. Observations with inconsistent or incomplete data and for which no manufacturer
model number could be found were dropped from the data set.
To collect data for VCRs CPI data collectors use data collection forms known as
checklists, which outline the product characteristics judged to be most important. When
the CPI representative completes the data collection form we get a description indicating
all the pertinent characteristics and the price of the item. (See Attachment A for the
RA031 Cluster 01A, Video Cassette Players/Recorders data collection form.) Collecting data
for electronic goods is not a simple task. Manufacturers and retailers use confusing
terminology and often use different names for the same feature. Consumers are left to ask
sales personnel for assistance to decipher technical information. Some of these
difficulties spill over into CPI data collection efforts. Where there were inconsistencies
or incompleteness in the data collected for this research effort, the manufacturer model
numbers obtained by CPI data collectors were matched to specifications provided by the
manufacturer Internet sites.
Although most VCRs are indeed capable of recording as well playback, there are units on
the market which are playback only. There were a total of thirteen player-only units in
the sample. There was an unsuccessful attempt to include unit type (player or
play/recorder) in the model; however the t-statistic did not come close to a reasonable
level of acceptance. The mean price for play only units was $126.50 compared to a mean
price of $195.26 for play/record units. These play-only observations were deleted from the
final data set, as it appears that the pricing structure for player-only units is
different than that of units that have recording ability.
Tape format is dominated by the Video Home System (VHS), VHS High Quality (VHS-HQ) or
Super VHS (S-VHS); the latter offers the best among analog formats, with 50 percent more
picture sharpness than standard VHS. The beta system, which was the early competitor to
VHS, is used primarily for commercial applications. The 8mm players are relegated to use
by those with 8mm camcorders that do not have converter with which to watch their 8mm
camcorder tapes on VHS. Finally, Digital VHS (D-VHS) first introduced in 1998 and designed
to be a partner with DirecTVSatellite System or the Dish Network, has not yet achieved
mainstream acceptance.
As expected, the sample proved to be skewed: While VHS had observations split between
VHS and S-VHS, there were no observations for beta tape, two observations for 8 mm and one
observation for digital. The digital and 8 mm observations were deleted from the sample to
allow focus on the more popular VHS and Super VHS formats. There seems to be no
discernible difference between VHS and VHS-HQ. Manufacturer reporting of this information
was inconsistent, and it became clear that consumers would have difficulty in discerning
if the units they were purchasing were equipped with HQ. Instead VHS and VHS-HQ variables
were combined, so by default, tape format was either VHS or Super VHS. Since VHS made up
an overwhelming majority of the sample it was chosen as the base variable for this
category.
Brand was dominated by four companies: Sony, Panasonic, JVC and RCA, which combined
made up 61 percent of the sample. Of the other 21 brands named, no other brand made up
more than five percent of the sample. Sony and JVC (which combined made up 31 percent of
the sample) were included in the model along with Zenith (five percent) and Proscan ( two
percent). Thus, 38 percent of the brands by volume of sales were explicitly included as
variables in the model. By implication brands not included in the model were grouped into
a miscellaneous "Other" category and designated as a variable. The direction and
magnitude for each of the included specifications met a priori expectations.
There is a direct relationship between the number of heads a VCR has and the quality of
the picture during playback, thus number of heads is a fundamental attribute of the VCR.
Most of the observations consisted of units with four heads, approximately 93 percent of
the sample. VCRs with two heads comprised approximately six percent and VCRs with six
heads made less than one percent. Although only a small percentage of the sample had two
or six heads, the corresponding variables proved to be statistically significant and met
expectations in terms of magnitude.
Hi-fi stereo units made up 81 percent of the sample, while mono-sound comprised 16
percent and surround sound two percent of the sample. With stereo sound as the base
variable in the category, the mono-sound variable displayed the expected direction and
magnitude and proved to be significant. The results for the surround sound variable were
not as anticipated and did not prove to be significant.
The variable dual tape well represents the feature of dual tape capability, which
allows the consumer to record tapes in addition to television shows. This feature is
associated exclusively with the GO Video brand. Despite only a few observations, this
variable proved to be large in terms of magnitude and significance. The GO Video brand has
invested heavily not only in the technology but also the legal concerns of exclusively
manufacturing a "dual well" machine. Thus, the dual-well VCR is a high-end type
of VCR.
Other features that were included as variables in the model were flying erase head
which permits smoother editing of tapes, the capability to advance through commercials or
omit commercials when recording, and "VCR plus " recording, which allows the
consumer to program the VCR to record a particular show using a five digit code.
A disappointing result of the modeling process was that the lines of horizontal output,
a measure of the quality of the picture produced, (the more lines the higher the quality),
could not be included in the model. Initially it was anticipated that the lines of
horizontal output would be fruitful; however, due to the technical nature of the
information and the inconsistency in its availability there was a low rate of successful
data capture. So while lines of horizontal output may be an important technical
characteristic, it remains unclear if and how consumers value this characteristic,
especially if they are unable to determine the lines of output for their unit. A couple of
other characteristics that may have suffered similar plights are Quasi S-VHS playback, and
multiple format conversion. Some common characteristics that did not prove significant
include automatic rewind, automatic head cleaner, child lock, and automatic clock set.
Remote and manufacturer warranty also did not prove to be significant.
Country of origin was a new collection initiative. Japan made up most of the sample at
42 percent, while 31 percent of the sample came from other countries in the Far East. The
remaining sample came from Mexico (seven percent) and the U.S. A. (three percent), while
in 17 percent of the observations the country of origin was not available. While country
of origin was given considerable attention the modeling results offered no compelling
reason to include country of origin as a variable.
Statistical results of the model are presented in the table below:
VCR Model
Variable Name
|
Parameter Estimate |
T-statistic |
Variable Name |
Parameter Estimate |
T-statistic |
Intercept |
4.98933 |
162.667 |
Other: |
|
|
Last price was sale |
-0.10264 |
-3.886 |
Dual well deck |
1.20147 |
12.572 |
Type: |
|
|
Flying head edit feature |
0.80020 |
9.149 |
Super VHS |
0.49856 |
9.789 |
Commercial skip/advance |
0.09392 |
3.676 |
VHS |
Base |
|
Inputs front & back |
0.29095 |
7.256 |
Brand: |
|
|
VCR plus |
0.08967 |
3.453 |
Proscan |
0.23676 |
2.897 |
Cable/satellite control |
0.04516 |
2.022 |
Sony |
0.21914 |
7.395 |
Type of Business Variables |
|
|
JVC |
0.07943 |
2.035 |
Appliance |
0.09483 |
2.759 |
Other brands not listed |
Base |
|
Electronic |
0.09096 |
3.078 |
Zenith |
-0.12257 |
-2.335 |
Discount Department |
-0.06642 |
-2.191 |
Audio: |
|
|
Warehouse |
-0.13498 |
2.759 |
Hi-fi stereo |
Base |
|
|
|
|
Mono Sound |
-0.19545 |
-6.108 |
|
|
|
Number of heads |
|
|
Region Variables |
|
|
Six video heads |
0.24494 |
2.012 |
Midwest Region |
-0.03334 |
-1.370 |
Four video heads |
Base |
|
|
|
|
Two video heads |
-0.27807 |
-6.218 |
|
|
|
N=439 R2=0.7581 Adjusted R2=0.7466 F Statistic=65.661
|
The R-squared of .7581 says that almost 76 percent of the variation in the dependent
variable is explained by the independent variables. This result compares to the Liegey and
Shepler hedonic model which had an R-squared value of 95 percent.(1) (See Attachment C.)
Although the hedonic models are similar in terms of types of variables included in the
model, the Liegey and Shepler model is clearly more encompassing in terms of features
characteristics, brand name and type of player. Although a comparison between the two
hedonic models may provide some insights and topics for debate, any comparison should
tempered by an understanding of the differences in approach for these two modeling
efforts.
The model developed in this research was based on consumer retail offer prices and
characteristics collected by CPI representatives. The Liegey and Shepler research was
based exclusively on data obtained from the Consumer Digest 1998 Annual Buying Guide. In
addition to the fact that these data are less current that the data used here, there is a
theoretical concern that the list prices such as those listed in the Consumer Digest do
not reflect prices that the consumer faces in the marketplace.(2) Using list prices that
do not equal consumer retail offer prices may give a higher R-squared value but provide
for a less accurate hedonic model. If this concern is true then it would be difficult to
compare a hedonic model based on consumer retail offer prices and a hedonic model based on
list prices. Also complicating comparisons between the two approaches is that the Liegey
and Shepler model is unable to account for the price effects of the type of business, the
region of the country or size of a city.
Comparing Quality Adjusted and Published Indexes
Simulating an index with quality adjusted VCR substitutions will illustrate the impact
of using the VCR regression model in calculating the CPI. The published index (without
quality adjustments) is recreated with CPI historical data. This recreation is then
compared to the simulated index that includes quality-adjusted substitutions. The
simulation of the published and quality adjusted indexes covers the time period from May
1999 to December 1999. Index price changes for the U.S. city level, such as those examined
in this study, were obtained by summing price changes over all (elementary) index areas
using aggregation weights derived from the Consumer Expenditure Survey.
VCRs are included in the Other video equipment item stratum (RA031) along with
camcorders, DVD players, satellite video products and other miscellaneous video products.
VCRs have an estimated 46 percent of the weight within Other video equipment.
During the time period from December 1997 to December 1999 the Other video equipment
index decreased 26.5 percent. The average monthly decline was 1.1 percent. The Other
video equipment index was redefined for the January 1998 CPI revision so a longer term
comparison is not available. Prior to the revision, VCRs were included in the Video
products other than televisions index. This index decreased 38.7 percent from December
1988 to December 1997 — an average monthly decline of 0.4 percent.
For the time period June 1999 to December 1999 Other video equipment had a total
of 1589 quotes priced. Over this time period there were 224 substitutions for an average
substitution rate of 14 percent. Of the 224 substitutions, 99 substitutes, or 44 percent,
were deemed to be 'comparable', meaning that 56 percent of the substitutes were coded as
non comparable and were included for index calculation using the 'class-mean imputation'
method.(3)
For VCRs alone there were a total of 130 substitutions during the June to December time
period. In the published index 51 percent of the VCR substitutions directly compared the
price of the price of the new item to the price of the previous item. There was one
observation coded as quality adjusted. The quality adjustment for this observation was not
based on parameter estimates from a hedonic model; the quality adjusted price was
determined by the analyst from information received from the representative. Finally,
price changes for the remainder of the substitutions were imputed using the class-mean
imputation method.
For the purpose of calculating the quality adjusted index all the substitutions were
reevaluated. One of the benefits of using a hedonic model in evaluating substitutions is
that the analyst has an opportunity to review price data and item characteristics with a
statistical tool, thus enabling him/her to render judgments based on statistics rather
than expert judgment alone. A direct result of this benefit was that the method of price
change for 64 percent (up from 51 percent for the published index) of the substitutions
used the direct comparison between the price of the new item and the price of the old
item. Twenty-seven percent of the substitutions were deemed to have changes in quality
that could be adjusted using the hedonic model results. Only nine percent of the
substitutions continued to use the class mean imputation method. The quality adjusted
index had an overall comparability ratio of 91 percent compared to 52 percent for the
published index. The use of the hedonic model to reevaluate substitutions impacts the
index in two ways: 1) via substitutions that are quality adjusted; and 2) through
substitutions that with additional information provided by the model can be directly
compared rather than use the class mean imputation method. From the table below the mean
price change for directly comparable quotes went from a negative 3.72 percent to a
negative 1.00-percent.
VCR Substitutions from June 1999 to December 1999
|
Published Index
Mean price
Number Percentage Change
|
Quality Adjusted Index
Mean price
Number Percentage Change
|
All substitutions |
130 100% -4.30 |
130 100% -1.26 |
Directly compared substitutions |
67 51% -3.72 |
83 64% -1.00 |
Quality Adjusted |
1 1% -9.10
|
35 27% -1.41 |
Class mean imputed (noncomparable) substitutions
|
62 48% -4.35 |
12 9% -1.85 |
Graphic presentations of the results of the RA031 index simulation, with and without
hedonic quality adjustments, are shown in Attachment B. The first graph shows a line graph
of index levels for the published and quality adjusted indexes from May 1999 to December
1999. The second graph illustrates the differences for one-month changes between the
published and quality adjusted indexes.
From May 1999 to December 1999 the quality adjusted index decreased 6.7 percent
compared to a 7.7-percent decrease for the published index.(4) The differences, quality
adjusted minus published, for the one-month changes ranged from a low -0.72 percentage
point to a high of 1.33 percentage point. The average difference for the seven month time
period was 0.15 percent. These results show that the CPI may have been overstating the
rate of price decline for item category of Other video equipment. That is, if the
CPI actually had used the regression model for VCRs, the index would have had a smaller
decline than the CPI actually shows.
The results of this study are not surprising given that Liegey and Shepler had a
similar although smaller difference (0.1 percent difference over a 12 month study) between
the published index and the quality adjusted index. Additionally, Kokoski, Waehrer, and
Rozaklis found similar results (1.7 percent difference over a 12 month study) for some
audio products.(5) Just as the Liegey and Shepler research was based on data from non-CPI
sources, the Kokoski, Waehrer and Rozaklis research was based on point-of-sale data
purchased from NPD, a private firm specializing in the collection and marketing of such
data for sale. NPD data more closely resembles CPI data than the Consumer Digest's list
price data, but differs in that NPD data covers a significantly wider product range than
CPI data. Although there are differences in the source of the data the index simulation
results can not be totally discounted.
It is clear the VCR is no longer a new, high tech consumer good, since 93 million U.S
households own at least one VCR, according to industry sources. As Liegey and Shepler
point out, the issue for the VCR index is not to capture falling prices that a high-tech
consumer good faces early in it's product cycle; rather, the VCR index faces the quality
and price change issues as they relate to a mature product.(6)
Conclusion
It is unclear what the future holds for the VCR. It is likely that the VCR will
continue to be popular in the near term. While someday in the future the VCR or at least
the VHS format will give way to some type of digital format, recent VCR sales have hit
record numbers. 1998 was a banner year for VCR sales, up eight percent from the previous
year, and the second consecutive record breaking year.(7) If the DVD does develop the
technology to record and continues its downward price trend then it is very likely that
the DVD player will make the VCR obsolete at some point in the future.
The CPI will begin to use hedonic regression models for VCRs beginning in April 2000.
Given the technological evolution of the consumer electronic market, in which VCRs
exist, it is likely that this model will not prove to be completely stable. CPI intends to
test the stability of the model using new data in the near future.
Notes
(1) Paul Liegey and Nicole Shepler, "Adjusting VCR Prices for quality
change: a study using hedonic methods," Monthly Labor Review, September 1999, page
13.
(2) Liegey and Shepler, footnote 20, page 32.
(3) See Marshall B Reinsdorf, Paul Liegey, and Kenneth J. Stewart, "New Ways
of Handling Quality Change in the U.S. Consumer Price Index," BLS working Paper no.
276 (Bureau of Labor Statistics 1996).
(4) In addition to quality adjusting the VCR substitutions, some of the impute
price changes for the class-mean substitutions (the noncomparable substitutions) in
the
Other Video Equipment index were recalculated since the inclusion of the quality
adjustments changed the information used in calculating the imputations.
(5) Mary Kokoski, Keith Waehrer, and Patricia Rozaklis, "Using Hedonic
Methods for Quality Adjustment in the CPI: The Consumer Audio Products Component,"
BLS draft paper 1999, p. 11.
(6) Paul Liegey and Nicole Shepler, "Using Hedonic Methods to Quality Adjust
VCR Prices: a Study Using Hedonic Methods," Monthly Labor Review, September 1999, pp.
23-24.
(7) http://
www.ce.org, visited on Jan12, 2000.
ATTACHMENT A
BUREAU OF LABOR STATISTICS U.S. DEPARTMENT OF LABOR
CONSUMER PRICE INDEX - ELI CHECKLIST______________________________________________________
collection outlet quote arranging
period: __ __ __ __ number: __ __ __ __ __ __ __ code: __ __ __ code: __ __ __ __
_________________________________________________________________________________________
ELI No./ cluster
title RA031 OTHER VIDEO EQUIPMENT code 01A
item availability: 1-AVAILABLE 2-ELI NOT SOLD 3-INIT INCOMPLETE
purpose of checklist: 1-INIT 2-INIT COMPL 3-SPEC CORR 4-SUB 5-REINIT 6-CHECK REV
_________________________________________________________________________________________
CURRENT PERIOD | SALES TAX
|
price _ _ _ _ _ _ . _ _ _ | included: YES NO
|
type of price: REG SALE |
|
|____________________________________________
|
YEAR-ROUND | in-season: JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
____________|____________________________________________________________________________
respondent: location:
_________________________________________________________________________________________
field message:
_________________________________________________________________________________________
CLUSTER 01A - VIDEO CASSETTE PLAYERS/RECORDERS
TYPE MANUFACTURER'S MODEL NUMBER
A1 Player Only
A2 Player/Recorder D99 ______________________________
TAPE FORMAT NUMBER OF VIDEO HEADS
B1 VHS E1 Two
B2 VHS HQ E2 Three
B3 Super VHS (S-VHS) E3 Four
B4 Beta E4 Five
B5 Extended Definition Beta (ED Beta) E5 Six
B6 8mm E99 Other,
B7 Hi 8mm
B8 Digital VHS (D-VHS) ______________________________
B9 Digital Video (DV)
B99 Other, LINES OF HORIZONTAL OUTPUT
______________________________ F99 ______________________________
BRAND AUDIO CAPABILITIES
C1 Emerson G1 Surround Sound
C2 Fisher G2 Hi-Fi Stereo
C3 GE G3 Monaural
C4 Hitachi H99 Other audio capability,
C5 JVC
C6 Mitsubishi ______________________________
C7 Panasonic I99 Other audio capability,
C8 Philips/Magnavox
C9 Proscan ______________________________
C10 RCA
C11 Samsung
C12 Sanyo
C13 Sharp
C14 Sony
C15 Toshiba
C16 Zenith
C99 Other,
______________________________
RA031-01A - VIDEO CASSETTE PLAYERS/RECORDERS - CONTINUED
GENERAL FEATURES OTHER FEATURES
J1 Dual well deck, both record and AG1 Front panel Audio/Video inputs
playback AH99 Other,
J2 Dual well deck, one record and
one playback ______________________________
K1 Quasi S-VHS Playback AI99 Other,
L1 Multiple format conversion
M1 Flying Erase Head ______________________________
N1 Automatic Rewind AJ99 Other,
P1 Automatic Head Cleaner
Q1 Cable and/or satellite dish ______________________________
channel control
R99 Other general feature, WARRANTY
AK1 One year parts and labor
______________________________ AK2 Two years parts and labor
AK3 Three years parts and labor
PROGRAMMING FEATURES AK99 Warranty, other type,
S1 On screen program guide
T1 Commercial Skip ______________________________
U1 Commercial Advance
V1 Skip Search COUNTRY OF ORIGIN
W1 Index Plus AL1 Not Available
X1 VCR Plus + Recording AL2 United States
Y1 Child Lock AL3 Japan
AA1 Automatic Clock Set AL99 Other,
AB1 Movie Advance
AC99 Other programming feature, ______________________________
______________________________ OTHER PRICE FACTORS
REMOTE CONTROL BA99 ______________________________
AD1 Controls VCR only
AD2 Controls same brand TV BB99 ______________________________
AD3 Controls other brand TVs
AE1 Illuminated Remote BC99 ______________________________
AF99 Other remote control feature,
** OTHER CLARIFYING INFORMATION
______________________________
CA99 ______________________________
CB99 ______________________________
CC99 ______________________________
_________________________________________________________________________________________
BLS 3400B (Rev. February 1995) RA031 page 3 of 16
Revised April 1999
DEFINITION OF TERMS
CLUSTER 01A-VIDEO CASSETTE PLAYERS/RECORDERS
8mm - Eight millimeter is a type of video tape.
AUTOMATIC CLOCK SET - The VCR reads instructions from a broadcast signal that
allows the VCR to set its own clock.
AUTOMATIC HEAD CLEANER - The machine is able to clean its own video heads.
AUTOMATIC REWIND - The tape rewinds automatically after play is complete.
BETA - Type of tape. Rare in consumer applications. Do not price a
professional model.
CABLE AND/OR SATELLITE DISH CHANNEL CONTROL - When the VCR is programmed to
record over a cable or satellite system, it is able to set the cable or
satellite system to the correct channel for recording.
CHILD LOCK - Freezes control of VCR except for timer functions.
COMMERCIAL ADVANCE - The VCR marks sections of commercials electronically and
fast forwards through them automatically during playback.
COMMERCIAL SKIP - The VCR omits commercials while recording.
DIGITAL VHS (D-VHS) - The video is stored in digital format on the VHS tape
rather than as an analog tape.
DIGITAL VIDEO (DV) - A particular standard for storing digital video information
used in VCRs and Camcorders.
DUAL WELL DECK - There are two places in the chassis of the VCR (wells) to input
tapes. Some types may permit recording in either of the wells.
EXTENDED DEFINITION BETA (ED BETA) - A system used in the Beta tape format which
provides superior video quality versus "standard" definition Beta.
FLYING HEAD ERASE - A special head mounted on the same spinning headwheel as
the recording heads that allows the VCR to create edited tapes with smoother
transitions than would be possible otherwise.
FRONT PANEL AUDIO/VIDEO INPUT - There is a place on the front panel of the VCR
where video input from another source such as a video camera or video game
can be connected.
HI-BAND 8mm (HI8 8mm) - A system used in eight millimeter tape format which
provides superior video quality versus "standard" eight millimeter.
HiFi STEREO - The VCR will decode and output two channels of audio information
(stereo).
INDEX PLUS - May create an on-screen listing of taped programs along with date
recorded and running time. Fast forwards to a selected program and plays it.
ATTACHMENT B
![](https://webarchive.library.unt.edu/web/20120927123042im_/http://www.bls.gov/cpi/cpivcr01.gif)
![](https://webarchive.library.unt.edu/web/20120927123042im_/http://www.bls.gov/cpi/cpivcr02.gif)
ATTACHMENT C
Liegey and Shepler VCR Model
Variable name
|
Parameter Estimate |
T-statistic |
Variable name |
Parameter Estimate |
T-statistic |
Intercept |
5.12849 |
179.013 |
Number of heads: |
|
|
Type: |
|
|
Two video heads |
-0.10864 |
-3.449 |
VHS Player |
-0.13886 |
-3.053 |
Four video heads |
Base |
|
VHS |
Base |
|
Six video heads |
0.48777 |
6.279 |
Quasi SVHS |
0.09705 |
1.877 |
Other: |
|
|
SVHS |
0.71605 |
16.697 |
Auto rewind |
0.12569 |
5.895 |
Dual deck VCR |
0.89027 |
17.211 |
Cable channel changer |
0.12856 |
5.540 |
Multi format converter |
1.38890 |
12.955 |
Child lock |
0.03977 |
2.002 |
Brand: |
|
|
Commercial advance |
0.17805 |
5.889 |
Marantz |
0.59280 |
7.445 |
Commercial skip |
0.11848 |
4.748 |
Sony/Toshiba/Mitsubishi |
0.22754 |
7.559 |
Flying head edit feature |
0.27088 |
7.539 |
Proscan |
0.15815 |
2.337 |
Automatic head cleaner |
0.03369 |
1.503 |
Other brands not listed |
Base |
|
Hi-fi stereo |
0.19133 |
9.333 |
Funai/Phillips/Symphonic |
-0.17155 |
-5.839 |
Index plus |
0.25869 |
2.356 |
Samsung |
-0.23819 |
-5.757 |
Skip search |
0.17100 |
6.988 |
|
|
|
Starsightâ |
0.56336 |
9.431 |
|
|
|
VCR plus |
0.12219 |
5.537 |
N = 176 R2 = 0.9581 Adjusted R2 = 0.9514 F statistic = 143.746
|
Last Modified Date: October 16, 2001