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                                                                   EXHIBIT 10.16



                            STOCK PURCHASE AGREEMENT


        THIS STOCK PURCHASE AGREEMENT (this "Agreement") is made as of the 11th
day of April 2000 by and between Venture Catalyst Incorporated, a Utah
corporation ("Purchaser"), and Howard Yen ("Seller").

        THE PARTIES HEREBY AGREE AS FOLLOWS:

1.      Purchase and Sale of Stock.

        A. Subject to the terms and conditions of this Agreement, Purchaser
agrees to purchase and Seller agrees to sell to Purchaser up to 318,182 shares
(the "Shares") of Common Stock, $0.001 par value per share (the "Common Stock"),
of PredictIt, Inc., a Delaware corporation (the "Company"). Concurrently with
the execution of this Agreement, Seller is delivering to Purchaser the stock
certificate representing the Shares, duly endorsed in blank or accompanied by
proper instruments of transfer duly signed by Seller in blank against payment of
the purchase price set forth in this Section 1 (the "Closing"). The exact number
of Shares shall be determined by dividing $350,000 by the average market price
of the Common Stock. The average market price of the Common Stock shall mean the
average of the closing bid price of the Common Stock reported on the
over-the-counter market for the five trading days prior to the Closing, but in
no event less that $1.10 per share of Common Stock.

        B. Purchase Price. Upon the terms and subject to the conditions set
forth in this Agreement, in reliance upon the representations, warranties,
covenants and agreements of Seller contained herein, and in exchange for the
Shares, Purchaser agrees to issue to Seller shares of Purchaser's Common Stock,
$0.001 par value per share (the "Purchaser Common Stock"). The number of shares
of Purchaser Common Stock to be issued by Purchaser hereunder shall be
determined by the formula set forth on Exhibit A (the "Purchase Price").

2.      Representations and Warranties of Seller.

        Seller hereby represents and warrants to Purchaser as follows:

               (a) Seller is the beneficial and record owner of the Shares and
        has valid and marketable title to the Shares, free and clear of any
        lien, pledge and encumbrance or any claim of any third party.

               (b) Seller has the necessary power and authority to enter into
        this Agreement, and this Agreement constitutes a valid and legally
        binding obligation of the Seller, enforceable in accordance with its
        terms except (i) as limited by applicable bankruptcy, insolvency,
        reorganization, moratorium, and other laws of general application
        affecting enforcement of creditors' rights generally, and (ii) as
        limited by laws relating to the availability of specific performance,
        injunctive relief, or other equitable remedies.



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               (c) No options, warrants or other rights to purchase any of the
        Shares have been granted by Seller.

               (d) Neither Seller nor the Company has entered into any contract,
        arrangement or understanding with any person or firm which may result in
        the obligation of Purchaser to pay any finder's fees, brokerage or
        agent's commissions or other like payments in connection with the
        negotiations leading to this Agreement or the consummation of the
        transactions contemplated hereby, and Seller is not aware of any claim
        or basis for any claim for payment of any finder's fees, brokerage or
        agent's commissions or other like payments in connection with
        negotiations leading to this Agreement or the consummation of the
        transactions contemplated hereby. Seller shall indemnify Purchaser for
        any claims arising out of any breach of the foregoing representation.

               (e) Seller represents that he understands that (i) the Purchaser
        Common Stock being acquired by Seller pursuant to this Agreement has not
        been registered under the Securities Act of 1933, as amended (the "1933
        Act") and is being issued in reliance upon the exemption afforded by
        Section 4(2) thereof for transactions by an issuer not involving any
        public offering, (ii) such Purchaser Common Stock must be held
        indefinitely unless a subsequent disposition thereof is registered under
        the 1933 Act or is exempt from such registration, (iii) such Purchaser
        Common Stock will bear a legend to such effect, and (iv) Purchaser will
        make a notation on its transfer books to such effect. Seller further
        represents that (i) such Purchaser Common Stock is being acquired for
        investment and without any present view toward distribution thereof to
        any other person, (ii) he will not sell or otherwise dispose of
        Purchaser Common Stock except in compliance with the registration
        requirements or exemption provisions under the 1933 Act, the rules and
        regulations thereunder, and as otherwise set forth by the Securities and
        Exchange commission (the "Commission"), (iii) he has knowledge and
        experience in financial and business matters and that he is capable of
        evaluating the risks and merits of an investment in Purchaser Common
        Stock, (iv) he has consulted with counsel, to the extent deemed
        necessary, as to all matters covered by this Agreement and has not
        relied upon Purchaser for any explanation of the application of the
        various federal or state securities laws with regard to the acquisition
        of such Purchaser Common Stock, (v) he has investigated and is familiar
        with the affairs, financial condition and prospects of Purchaser, and
        has been given sufficient access to and has acquired sufficient
        information about Purchaser to reach an informed and knowledgeable
        decision to acquire such Purchaser Common Stock, and (vi) he is able to
        bear the economic risks of such an investment.

3.      Representations and Warranties of Purchaser.

        Purchaser hereby represents and warrants to Seller as follows:

                      (a) Purchaser has the necessary corporate power and
        authority to enter into this Agreement and this Agreement constitutes a
        valid and legally binding obligation of Purchaser, enforceable in
        accordance with its terms, except (i) as limited by applicable
        bankruptcy, insolvency, reorganization, moratorium, and other laws of
        general application affecting enforcement of creditors' rights
        generally, and (ii) as limited by laws relating to the availability of
        specific performance, injunctive relief, or other equitable remedies.



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        The Purchaser Common Stock, when issued in accordance with this
        Agreement, has been duly issued and shall be fully paid and
        non-assessable.

               (b) Purchaser represents that he understands that (i) the Shares
        being acquired by Purchaser pursuant to this Agreement has not been
        registered under the Securities Act of 1933, as amended (the "1933 Act")
        and is being sold in a transaction not involving any public offering,
        (ii) such Shares must be held indefinitely unless a subsequent
        disposition thereof is registered under the 1933 Act or is exempt from
        such registration, and (iii) such Shares will bear a legend to such
        effect. Purchaser further represents that (i) such Shares are being
        acquired for investment and without any present view toward distribution
        thereof to any other person, (ii) it will not sell or otherwise dispose
        of Shares except in compliance with the registration requirements or
        exemption provisions under the 1933 Act, the rules and regulations
        thereunder, and as otherwise set forth by the Securities and Exchange
        commission (the "Commission"), (iii) he has knowledge and experience in
        financial and business matters and that he is capable of evaluating the
        risks and merits of an investment in Shares, (iv) he has consulted with
        counsel, to the extent deemed necessary, as to all matters covered by
        this Agreement and has not relied upon Seller for any explanation of the
        application of the various federal or state securities laws with regard
        to the acquisition of such Shares, (v) he has investigated and is
        familiar with the affairs, financial condition and prospects of the
        Company, and has been given sufficient access to and has acquired
        sufficient information about the Company to reach an informed and
        knowledgeable decision to acquire such Shares, and (vi) he is able to
        bear the economic risks of such an investment.

               (c) Purchaser has not entered into any contract, arrangement or
        understanding with any person or firm which may result in the obligation
        of Seller to pay any finder's fees, brokerage or agent's commissions or
        other like payments in connection with the negotiations leading to this
        Agreement or the consummation of the transactions contemplated hereby,
        and Purchaser is not aware of any claim or basis for any claim for
        payment of any finder's fees, brokerage or agent's commissions or other
        like payments in connection with negotiations leading to this Agreement
        or the consummation of the transactions contemplated hereby. Purchaser
        shall indemnify Seller for any claims arising out of any breach of the
        foregoing representation.

4.      Registration Rights.

4.1     Registration Procedures. The Purchaser shall:

               (a) as soon as practicable after the Closing, but in any event
        within 30 days after the Closing, prepare and file with the Commission a
        registration statement on appropriate form (the "Registration
        Statement") pursuant to the 1933 Act relating to the resale of the
        Purchaser Common Stock by the Seller;

               (b) use its best efforts, subject to receipt of necessary
        information from Seller, to cause the Registration Statement to become
        effective no later than 60 days after the Registration Statement is
        filed by Purchaser;



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               (c) prepare and file with the Commission such amendments and
        supplements to the Registration Statement and the prospectus used in
        connection therewith as may be necessary to keep the Registration
        Statement effective until the earlier of (i) twelve months after the
        effective date of the Registration Statement or (ii) the date on which
        all of the Purchaser Common Stock have been sold by Seller pursuant to
        the Registration Statement or Rule 144 under the 1933 Act or any other
        rule of similar effect;

               (d) furnish to the Seller with respect to the Purchaser Common
        Stock registered under the Registration Statement such reasonable number
        of copies of prospectuses in order to facilitate the public sale or
        other disposition of all or any of the Purchaser Common Stock by the
        Seller; provided, however, that the obligation of Purchaser to deliver
        copies of prospectuses to Seller shall be subject to the receipt by
        Purchaser of reasonable assurances from Seller that Seller will comply
        with the applicable provisions of the 1933 Act and of such other
        securities or blue sky laws as may be applicable in connection with any
        use of such prospectuses;

               (e) file documents required of Purchaser for normal blue sky
        clearance in states reasonably requested in writing by Seller; provided,
        however, that Purchaser shall not be required to qualify to do business
        or consent to service of process in any jurisdiction in which it is not
        now so qualified or has not so consented; and

               (f) notify Seller at any time when a prospectus relating thereto
        is required to be delivered under the 1933 Act of the happening of any
        event as a result of which the prospectus included the Registration
        Statement, as then in effect includes an untrue statement of a material
        fact or omits to state a material fact required to be stated therein or
        necessary to make the statements therein not misleading in the light of
        the circumstances then existing.

               (g) bear all expenses in connection with the procedures in
        paragraphs (a) through (e) of this Section 4.1 and the registration of
        the Purchaser Common Stock pursuant to the Registration Statement, other
        than fees and expenses, if any, of counsel or other advisers to Seller
        or underwriting discounts, brokerage fees and commissions incurred by
        the Seller, if any.

4.2 Transfer of Shares After Registration. Seller agrees that it will not effect
any disposition of the Purchaser Common Stock or its right to purchase Purchaser
Common Stock that would constitute a sale within the meaning of the Securities
Act, except as contemplated in the Registration Statement referred to in Section
4.1, and that it will promptly notify Purchaser of any changes in the
information set forth in the Registration Statement regarding Seller or its Plan
of Distribution.



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4.3     Indemnification.

               (a) Purchaser agrees to indemnify and hold harmless Seller and
        each person, if any, who controls Seller within the meaning of the 1933
        Act, against any losses, claims, damages, liabilities or expenses, joint
        or several, to which Seller or such controlling person may become
        subject, under the Securities Act, the Securities Exchange Act of 1934,
        as amended (the "1934 Act"), or any other federal or state statutory law
        or regulation, or at common law or otherwise (including in settlement of
        any litigation, if such settlement is effected with the written consent
        of Purchaser), insofar as such losses, claims, damages, liabilities or
        expenses (or actions in respect thereof as contemplated below) arise out
        of or are based upon any untrue statement or alleged untrue statement of
        any material fact contained in the Registration Statement, or any
        amendment or supplement thereto, or arise out of or are based upon the
        omission or alleged omission to state in any of them a material fact
        required to be stated therein or necessary to make the statements in any
        of them, in light of the circumstances under which they were made, not
        misleading, and will reimburse Seller and each such controlling person
        for any legal and other expenses as such expenses are reasonably
        incurred by Seller or such controlling person in connection with
        investigating, or defending, compromising or paying any such loss,
        claim, damage, liability, expense or action; provided, however, that
        Purchaser will not be liable in any such case to the extent that any
        such loss, claim, damage, liability or expense arises out of or is based
        upon (i) an untrue statement or alleged untrue statement or omission or
        alleged omission made in the Registration Statement, the Prospectus or
        any amendment or supplement thereto in reliance upon and in conformity
        with written information furnished to Purchaser by or on behalf of
        Seller expressly for use therein, or (ii) the failure of Seller to
        comply with the covenants and agreements contained in Section 4.2 hereof
        respecting sale of the Purchaser Common Stock, or (iii) any statement or
        omission in any prospectus that is corrected in any subsequent
        prospectus that was delivered to Seller prior to the pertinent sale or
        sales by Seller.

               (b) Seller will severally indemnify and hold harmless Purchaser,
        each of its directors, each of its officers who signed the Registration
        Statement and each person, if any, who controls Purchaser within the
        meaning of the 1933 Act, against any losses, claims, damages,
        liabilities or expenses to which Purchaser, each of its directors, each
        of its officers who signed the Registration Statement or controlling
        person may become subject, under the 1933 Act, the 1934 Act, or any
        other federal or state statutory law or regulation (including in
        settlement of any litigation, if such settlement is effected with the
        written consent of Seller) insofar as such losses, claims, damages,
        liabilities or expenses (or actions in respect thereof as contemplated
        below) arise out of or are based upon (i) any failure to comply with the
        covenants and agreements contained in Section 4.2 hereof respecting the
        sale of the Purchaser Common Stock or (ii) any untrue or alleged untrue
        statement of any material fact contained in the Registration Statement,
        the prospectus, or any amendment or supplement thereto, or arise out of
        or are based upon the omission or alleged omission to state therein a
        material fact required to be stated therein or necessary to make the
        statements therein not misleading, in each case to the extent, but only
        to the extent, that such untrue statement or alleged untrue statement or
        omission or alleged omission was made in the Registration Statement, the
        prospectus, or any amendment or



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        supplement thereto, in reliance upon and in conformity with written
        information furnished to Purchaser by or on behalf of Seller expressly
        for use therein, and will reimburse Purchaser, each of its directors,
        each of its officers who signed the Registration Statement or
        controlling person for any legal and other expense reasonably incurred
        by Purchaser, each of its directors, each of its officers who signed the
        Registration Statement or controlling person in connection with
        investigating, defending, settling, compromising or paying any such
        loss, claim, damage, liability, expense or action.

4.4     Certain Information.

               With a view to making available to Seller the benefits of certain
        rules and regulations of the Commission which may permit the sale of the
        Purchaser Common Stock to the public without registration. Purchaser
        agrees to use its best efforts to:

                      (a) Make and keep public information available, as those
               terms are understood and defined in Rule 144 or any similar or
               analagous rule promulgated under the 1933 Act, at all times:

                      (b) file with the Commission, in a timely manner, all
               reports and other documents required of Purchaser under the 1934
               Act; and

                      (c) furnish to Seller upon request a written statement by
               Purchaser as to its compliance with the reporting requirements of
               said Rule 144 and of the 1934 Act, a copy of the most recent
               annual or quarterly report of Purchaser, and such other reports
               and documents as Seller may reasonably request in availing
               himself of any rule or regulation of the Commission allowing him
               to sell any such securities without registration.

5.      Miscellaneous.

               (a) Neither Seller nor Purchaser nor any of their respective
        successors, agents, affiliates, directors, officers, employees or
        assigns shall issue any press release or other form of public comment
        relating to the matters set forth in this Agreement without the prior
        consent of the other party, which consent shall not be unreasonably
        withheld; provided, however, nothing herein shall be construed to
        restrict any party from any disclosure required by law, following prior
        written notice to the other party. Nothing in this Paragraph 5 (a) shall
        be construed as creating any liability on any other party for the
        disclosure made by a party, with or without such other party's prior
        consent.



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               (b) The parties hereto will at any time, and from time to time
        after the Closing, upon request of the other party, execute, acknowledge
        and deliver all such further acts, deeds, assignments, transfers,
        conveyances, powers of attorney and assurances as may be required to
        carry out the intent of this Agreement, and to transfer and vest title
        to any Shares being transferred hereunder, and to protect the right,
        title and interest in and enjoyment of all of the Shares sold, granted,
        assigned, transferred, delivered and conveyed pursuant to this
        Agreement; provided, however, that this Agreement shall be effective
        regardless of whether any such additional documents are executed.

               (c) This Agreement shall be binding upon Purchaser, Seller, their
        respective administrators, legal representatives, successors, and
        permitted assigns. Nothing in this Agreement, expressed or implied, is
        intended to confer upon any person, other than the parties hereto, any
        rights or remedies under or by reason of this Agreement.

               (d) The representations and warranties contained herein shall
        survive the execution and delivery of this Agreement and the
        consummation of the transactions contemplated hereby and remain in full
        force and effect, notwithstanding any investigation at any time made by
        or on behalf of the parties.

               (e) This Agreement shall be construed in accordance with and
        governed by the laws of the State of California, without regard to
        principles of conflicts of laws.

               (f) The parties to this Agreement hereby agree that an award of
        damages alone is inadequate to remedy a breach of the terms of this
        Agreement, and that specified performance, injunctive relief, or other
        equitable remedy is the only way by which the intent of this Agreement
        may be adequately realized upon breach by one or more of the parties
        hereto. Such remedy shall, however, be cumulative and not exclusive, and
        shall be in addition to any other remedy which the parties may have.

               (g) This Agreement constitutes the entire agreement between the
        parties hereto with respect to the subject matter hereof, and may be
        amended only by a writing executed by all of the parties.

               (h) If for any reason whatsoever, any one or more of the
        provisions of this Agreement shall be held or deemed to be inoperative,
        unenforceable or invalid as applied to any particular case or in all
        cases, such circumstances shall not have the effect of rendering such
        provision invalid in any other case or of rendering any of the other
        provisions of this Agreement inoperative, unenforceable or invalid.

               (i) Neither this Agreement nor any of the parties' rights
        hereunder shall be assignable by any party hereto without the prior
        written consent of the other parties hereto and any purported assignment
        without such consent shall be null and void.

               (j) This Agreement may be executed in any number of counterparts,
        each of which shall be considered an original but all of which shall
        constitute the agreement by and among the parties.



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               (k) Each of the parties hereto shall be responsible for its own
        fees and expenses, including all legal and accounting fees incurred in
        connection with this transaction.


        IN WITNESS WHEREOF, the Purchaser and Seller have duly executed and
delivered this Agreement as of the date first above written.


VENTURE CATALYST INCORPORATED,
a Utah corporation


By:     /s/  Sanjay Sabnani
        --------------------------------
        Title: President

HOWARD YEN


By:     /s/  Howard Yen
        --------------------------------
        Title:
               -------------------------



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                                    EXHIBIT A




x  =[   a/b  ]
     --------
         z

where

a  =  $350,000

b  =  the average of the closing bid price of the Common Stock reported on the
      over-the-counter market for the five trading days prior to Closing, but in
      no event greater less than $1.10 per Share

z  =  the average of the last sale price of the Purchaser Common Stock as
      reported on the Nasdaq National Market for the five trading days prior to
      Closing

x  =  the number of shares of Purchaser Common Stock

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                   Amendment No. 1 to Stock Purchase Agreement


        This Amendment No. 1 to Stock Purchase Agreement is made as of the 18th
day of April, 2000 by and between Venture Catalyst Incorporated, a Utah
corporation ("Purchaser'), and Howard Yen ("Seller").

        THE PARTIES HEREBY AGREE to amend that certain Stock Purchase Agreement
dated as of April 11, 2000 between the parties (the "Agreement") as follows:

1.      For purposes of determining the number of Shares for the Agreement, the
        average market price of the Common Stock shall be fixed at $1.14062.

2.      For purposes of determining the average of the last sale price of the
        Purchaser Common Stock for the Agreement, such price shall be fixed at
        $4.5125.

3.      Except as amended hereby, the Agreement shall continue in full force and
        effect. Defined terms used herein and not otherwise defined shall have
        the meanings set forth in the Agreement.


        IN WITNESS WHEREOF, the Purchaser and Seller have duly executed and
delivered this Agreement as of the date first above written.

VENTURE CATALYST INCORPORATED,
A Utah corporation


By:     /s/  Sanjay Sabnani
        --------------------------------
        Title: President


HOWARD YEN


By:     /s/  Howard Yen
        --------------------------------
        Title:
               -------------------------



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