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                                                                    EXHIBIT 10.3

                                 AMENDMENT NO. 1
                           TO THE PERSONNEL AGREEMENT
                                     BETWEEN
                                  ARBITRON INC.
                                       AND
                              CERIDIAN CORPORATION


THIS AMENDMENT NO. 1 TO THE PERSONNEL AGREEMENT by and between Arbitron Inc., a
Delaware Corporation formerly known as Ceridian Corporation ("Arbitron"), and
Ceridian Corporation, a Delaware corporation formerly known as New Ceridian
Corporation ("Ceridian"), is entered into as of April 3, 2001.

WHEREAS, Arbitron and Ceridian entered into a Personnel Agreement dated as of
February 14, 2001 (the "Personnel Agreement");

WHEREAS, the Personnel Agreement provided for the conversion of stock options
and restricted stock based on the relationship between the trading prices of
Arbitron prior to the Distribution Date and Arbitron and Ceridian after the
Distribution Date, so that the intrinsic value of the stock options before the
Distribution Date will be equivalent to the intrinsic value of the stock options
after the Distribution Date;

WHEREAS, on the Distribution Date, Arbitron was removed from the S&P 500 and
Ceridian was added to the S&P 400, this substantially increased the trading
volume and impacted the price of Ceridian before and after the Distribution
Date;

WHEREAS, Arbitron and Ceridian wish to amend the Personnel Agreement to (1)
adjust the stock option conversion formulas for Ceridian employees and retirees,
decedents and certain other former Arbitron employees to remove the external
impact of the large volume of trading in Ceridian's stock as a result of the
changes in the S&P 500 and S&P 400, (2) adjust the restricted stock conversion
formulas to remove the external impact of the large volume of trading in
Ceridian's stock as a result of the changes in the S&P 500 and S&P 400, and (3)
to adjust the Arbitron stock option formulas to reflect the fact that Arbitron
traded on a post reverse spin and post reverse stock split basis after the
Distribution Date;

NOW, THEREFORE, in consideration of the foregoing premises and for other good
and valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties hereto hereby agree as follows:

1.      Section 5.4.  The text of Section 5.4 shall be deleted in its entirety
        and be replaced with the following:

        "5.4 Corporation Stock Option Plans. The Corporation shall continue in
        effect each stock option plan under which any person holds an
        outstanding option to purchase shares of the Corporation's common stock
        after the Effective Time. Except as otherwise provided in Section 5.5,
        each Ceridian Option held by a person other than a New Ceridian
        Optionee, whether or not exercisable as of the Effective Time, shall be
        adjusted in accordance with the following rules.

               (a) The price to be paid for each share of Arbitron common stock
               under the option shall be equal to the product of the per share
               exercise price of the Ceridian
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               Option and the Arbitron Price Ratio, such product to be rounded
               to the nearest whole cent; and.

               (b) The number of shares of Arbitron common stock to be issued in
               the exchange shall be equal to the quotient obtained by dividing
               the number of shares covered by the existing Ceridian Option by
               the Arbitron Price Ratio; such quotient to be rounded to the
               nearest full share."

2.      Section 5.5.  The text of Section 5.5 shall be deleted in its entirety
        and be replaced with the following:

        "5.5   Retiree, Decedent and Other Options. Any Arbitron Option held by
        (i) a Former Arbitron Employee or Former New Ceridian Employee who was
        entitled to continue benefits as a retired employee of the Corporation
        following his or her termination of employment, (ii) a retired
        non-employee director of the Corporation, (iii) the successors of an
        individual who is deceased, or (iv) a former director of ABR Information
        Services, Inc. shall, notwithstanding the preceding provisions of this
        article, be converted to separate options to purchase common stock of
        Arbitron (an "Arbitron Retiree Option") and New Ceridian (a "New
        Ceridian Retiree Option") as follows:

               (a) The number of shares subject to each New Ceridian Retiree
               Option shall be equal to the product of (i) the number of shares
               subject to the related Ceridian Option and (ii) a fraction, the
               numerator of which is the exercise price per share of the related
               Ceridian Option and the denominator of which is the sum of (x)
               the exercise price per share of the New Ceridian retiree Option
               plus (y) a fraction, the numerator of which is the exercise price
               per share of the Arbitron Retiree Option and the denominator of
               which is five, which product shall be rounded to the nearest
               whole share.

               (b) The exercise price per share of each New Ceridian Retiree
               Option shall be equal to the product of (i) New Ceridian
               Post-Distribution Price and (ii) a fraction, the numerator of
               which is equal to the exercise price per share of the related
               Ceridian Option and the denominator of which is the closing price
               of Ceridian Common Stock on the last trading day immediately
               before the Distribution Date, which product shall be rounded to
               the nearest whole cent.

               (c) The number of shares subject to each Arbitron Retiree Option
               shall be an amount equal to the quotient of the number of shares
               subject to each New Ceridian Retiree Option (as determined under
               paragraph (a) above) divided by five, which quotient shall be
               rounded to the nearest whole share.

               (d) The exercise price per share of each Arbitron Retiree Option
               shall be equal to the product of (i) the Arbitron
               Post-Distribution Stock Price by (ii) a fraction, the numerator
               of which is the exercise price per share of the related Ceridian
               Option and the denominator of which is the closing price of
               Ceridian Common Stock on the last trading day immediately before
               the Distribution Date, which product shall be rounded to the
               nearest whole cent."


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3.      Section 5.7.  The text of Section 5.7 shall be deleted in its entirety
        and be replaced with the following:

        "5.7   Option Definitions.  For purposes of this Article,

               (a) "Arbitron Post-Distribution Price" shall be the quotient
               obtained by dividing the volume-weighted average price of the
               common stock of Arbitron during the three consecutive trading
               days immediately following the Distribution Date.

               (b) "Arbitron Price Ratio" shall be the quotient obtained by
               dividing the Arbitron Post-Distribution Price by the Ceridian
               Pre-Distribution Price.

               (c) "Ceridian Pre-Distribution Price" shall be the
               volume-weighted average price of the common stock of the
               Corporation during the three consecutive trading days immediately
               prior to the Distribution Date.

               (d) "New Ceridian Post-Distribution Price" shall be equal to the
               opening price of common stock of New Ceridian on the first
               trading day immediately following the Distribution Date.

               (e) "New Ceridian Price Ratio" shall be the quotient obtained by
               dividing the New Ceridian Post-Distribution Price by the closing
               price of Ceridian Common Stock on the last trading day
               immediately before the Distribution Date."

4.      Section 5.9.  The text of Section 5.9 shall be deleted in its entirety
        and be replaced with the following:

        "5.9   Restricted Stock.  Before the Effective Time, New Ceridian shall
               establish (and the Corporation as sole stockholder of New
               Ceridian shall approve) a restricted stock plan that will benefit
               the New Ceridian Employees and the members of the board of
               directors of New Ceridian who, as of the Effective Time, hold
               restricted stock under one or more restricted stock plans of the
               Corporation. The shares of New Ceridian common stock issued as a
               distribution in respect of such shares of restricted stock shall
               remain subject to the same restrictions to which such restricted
               shares were subject. In addition, New Ceridian shall, to the
               extent that the cessation of employment or of a directorship with
               the Corporation at the Effective Time causes the forfeiture of
               any such restricted stock, provide for the distribution of shares
               of New Ceridian common stock to the affected persons, subject to
               the same restrictions to which the forfeited stock was subject,
               under the new restricted stock plan. The number of shares of New
               Ceridian common stock subject to such replacement award shall be
               equal to the product of (i) the number of such forfeited shares
               of restricted stock and/or deferred stock (adjusted for the
               one-for-five reverse stock split) by (ii) a fraction, the
               numerator of which is the Arbitron Post-Distribution Price and
               the denominator of which is the New Ceridian Post-Distribution
               Price, such product to be rounded to the nearest whole share."


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5.      Full Force. Except as amended pursuant to this Agreement, the Personnel
        Agreement shall remain in full force and effect in accordance with its
        original terms.

6.      Definitions. To the extent a term is not defined herein, such term shall
        have the meaning provided for in the Personnel Agreement.

7.      Counterparts. This Agreement may be executed in one or more
        counterparts, all of which shall be considered one and the same
        agreement, and shall become effective when one or more such counterparts
        have been signed by each of the parties and delivered to the other
        party.

IN WITNESS WHEREOF, the parties have caused this Agreement to be duly executed
as of the day and year first above written.

<TABLE>
<S>                                                <C>
ARBITRON INC.                                      CERIDIAN CORPORATION


By:  /s/ Dolores L. Cody                           By:  Gary M. Nelson
     ---------------------------------------            -------------------------------

Its:  Executive Vice President, Legal and          Its:    Vice President, General
      Business Affairs, Chief Legal Officer                Counsel and Secretary
      and Secretary
</TABLE>




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